HAZARDS VULNERABILITY ANALYSIS...Natural and mancreated disasters were then - reviewed to determine...

Chester County Hazard Vulnerability Analysis

July 2009

CHESTER COUNTY HAZARD VULNERABILITY ANALYSIS

July 2009

This analysis was undertaken in cooperation with state and federal efforts to develop an awareness of the hazards

facing each county as a basis for improving emergency services and emergency management at all levels

of government.

Prepared by: URS Corporation

Foster Plaza 4, Suite 300 501 Holiday Drive

Pittsburgh, Pennsylvania 15220

with the assistance of: Chester County Department of Emergency Services,

Chester County Planning Commission, Chester County Water Resources Authority,

and Pennsylvania Emergency Management Agency.

Edward J. Atkins, Director Chester County Department of Emergency Services


i July 2009

TABLE OF CONTENTS

I. INTRODUCTION ......................................................................................................... 1

A. Purpose ................................................................................................................. 1 B. Method of Analysis .............................................................................................. 1 C. Selection of Hazards ............................................................................................ 2

II. COUNTY PROFILE ................................................................................................... 3

A. General Information ............................................................................................. 3 B. Interesting Highlights........................................................................................... 4 C. Physical Features ................................................................................................. 5 D. History.................................................................................................................. 6 E. Current Land Use ................................................................................................. 7 F. Census Designated Places .................................................................................... 8 G. Municipality-Level Population Projections (Year 2030) ..................................... 8

III. NATURAL HAZARDS............................................................................................ 39

A. Floods ................................................................................................................. 39 B. Winter Storms .................................................................................................... 40 C. Tornadoes, Hurricanes, and Wind Storms ......................................................... 41 D. Droughts and Water Supply Deficiencies .......................................................... 42 E. Earthquakes ........................................................................................................ 43

IV. HUMAN-CAUSED HAZARDS .............................................................................. 72

A. Dam Failures ...................................................................................................... 72 B. Hazardous Materials .......................................................................................... 72 C. Fire Hazards ....................................................................................................... 75 D. Transportation Accidents ................................................................................... 76 E. Energy Emergencies .......................................................................................... 77 F. Civil Disorders ................................................................................................... 78 G. Fixed Nuclear Facilities ..................................................................................... 80 H. Nuclear Attack ................................................................................................... 80

V. SUMMARY .............................................................................................................. 105

VI. REFERENCES ....................................................................................................... 106


ii July 2009

TABLES

Table 1. Number of Business Establishments in Chester County......................12 Table 2. Chester County Open Space and Recreation Areas .............................14 Table 3. Major Retail Centers in Chester County ..............................................16 Table 4. Major Business Parks in Chester County.............................................18 Table 5. Total Housing Units in Chester County ...............................................19 Table 6. Existing Land Use in Chester County ..................................................28 Table 7. Southeastern Pennsylvania County Comparisons ................................32 Table 8. Chester County Municipal Population Change....................................34 Table 9. Chester County Municipal Population Projections ..............................36 Table 10. Significant Flood Events in Chester County ........................................46 Table 11. Seasonal Precipitation Statistics ..........................................................51 Table 12. Monthly Precipitation Statistics ...........................................................52 Table 13. Annual Precipitation ............................................................................53 Table 14. Significant Winter Storms in Chester County .....................................55 Table 15. Annual Snow Activity..........................................................................56 Table 16. Total Snowfall – Chester County .........................................................57 Table 17. Average Temperature – Chester County..............................................58 Table 18. Major Wind Storms in Chester County since 1979 .............................59 Table 19. Pennsylvania Tornado Frequency by Month .......................................61 Table 20. Highest Sustained Wind Speed (One-minute average) ........................64 Table 21. Highest Sustained Wind Speeds and Peak Instantaneous Gusts ..........65 Table 22. Drought Emergencies in Chester County since 1960 ..........................66 Table 23. Sample Chester County Observation Well Report ..............................70 Table 24. Chester County Dams ..........................................................................83 Table 25. Hazardous Materials Incidents Overview ............................................85 Table 26. Chester County Hazardous Materials Incidents Detail ........................86 Table 27. Superfund Sites in Chester County ......................................................89 Table 28. Chester County Pipelines .....................................................................90 Table 29. Chester County Terminals/Pumping Stations ......................................92 Table 30. Pennsylvania at Risk Population in the Vicinity of a Nuclear Power

Plant ...................................................................................................102


iii July 2009

FIGURES

Figure 1. Comparison of 1995 and 2000 Employment Sectors in Chester County and Surrounding Region ......................................................................11

Figure 2. Chester County Open Space and Recreation Areas .............................13 Figure 3. Major Retail Centers in Chester County ..............................................15 Figure 4. Major Business Parks in Chester County.............................................17 Figure 5. New Housing in Chester County .........................................................20 Figure 6. Municipalities of Chester County ........................................................21 Figure 7. Chester County Median Household Income ........................................22 Figure 8. Population Pyramids by Age Group ....................................................23 Figure 9. Geographical Setting of Chester County .............................................24 Figure 10. Regional Setting of Chester County ....................................................25 Figure 11. Physical Features of Chester County ...................................................26 Figure 12. Chester County Major Streams ............................................................27 Figure 13. Chester County Population Density .....................................................29 Figure 14. Census Urbanized Areas ......................................................................30 Figure 15. Census Designated Places, 2000 ..........................................................31 Figure 16. Delaware River Basin ..........................................................................47 Figure 17. Susquehanna River Basin ....................................................................48 Figure 18. Chester County Watersheds .................................................................49 Figure 19. Chester County Volunteer Rainfall Observer Network – Rain Gauge

Locations ..............................................................................................50 Figure 20. Flood Hazard Areas .............................................................................54 Figure 21. US Reported Tornadoes and Average Number of Deaths per Year ....62 Figure 22. Wind Roses for Regional Pennsylvania Airports ................................63 Figure 23. Chester County Public Water Facilities and Service Areas .................67 Figure 24. Chester County Groundwater Level Monitoring Wells .......................68 Figure 25. Sample Groundwater Monitoring Well Status Map ............................69 Figure 26. Earthquake Locations in Pennsylvania ................................................71 Figure 27. Chester County Dam Locations ...........................................................84 Figure 28. Natural Gas and Petroleum Product Transmission Lines ....................91 Figure 29. Public Airports Serving Chester County..............................................93 Figure 30. Arrival and Departure Air Routes – Philadelphia International

Airport ..................................................................................................94 Figure 31. Chester County Freight Railroad Service ............................................95 Figure 32. Chester County Passenger Rail Service ...............................................96 Figure 33. Public Transportation Service in Chester County ................................97 Figure 34. Chester County Highways ...................................................................98 Figure 35. Peach Bottom Atomic Power Station Plume Exposure Pathway ........99 Figure 36. Limerick Generating Station Plume Exposure Pathway ....................100 Figure 37. 50 Mile Radii of Nuclear Power Plants Within or Affecting

Pennsylvania ......................................................................................101 Figure 38. Chester County Population at Risk of a Nuclear Attack ....................103 Figure 39. Pennsylvania Populations at High Risk of a Nuclear Attack .............104


1 July 2009

I. INTRODUCTION

A. Purpose

1. To develop a common awareness among emergency service agencies, public officials and the public of the major hazards existing in Chester County, Pennsylvania.

2. To identify the locations of hazards and the number of persons and major facilities that may be vulnerable to each type of hazard.

3. To encourage cooperative management of emergency situations based on a common understanding of hazards and their impacts.

4. To enhance the emergency and disaster response and recovery capabilities for all hazards.

5. To encourage plans and actions for preventative measures and effective response to preserve life and property in areas vulnerable to effects of natural and human-caused hazards.

B. Method of Analysis

The frequency of disaster situations, and the effects or severity of the event are important as a basis for planning, mitigation and emergency response. Natural hazards tend to recur periodically, whereas human-caused events tend to change as technology and methodology change. For purposes of this analysis, most historical studies include a ten year span, unless otherwise indicated. Four criteria were selected to assure a systematic and comprehensive approach to analyzing all hazards: 1. History is a record of past events helpful in evaluating natural hazards. Both the

frequency and severity of past events are useful in predicting the future. Past records of human-caused events also offer valuable information when tempered with the knowledge of prevention, and changes in technology that may reduce the frequency or severity of such an event. Other human-caused hazards exist and must be analyzed without the benefit of past experience due to the newness of the hazard.

2. Vulnerability is the susceptibility of a community to destruction, injury and/or death.

This degree of vulnerability may be related to geographic location or to the type of facility or structure. Certain population groups may be more vulnerable to some hazards due to immobility, or inability to take protective action.

3. Maximum threat or worst-case disasters should be considered for each hazard. It

provides for an upper boundary for the level of preparedness that may be necessary.

4. Probability of an occurrence is another important factor to be considered when deciding priorities, appropriate for individual hazards. An event which occurs


2 July 2009

annually, though relatively minor in impact may deserve more emphasis than a major event which occurs once in 50 to 100 years.

C. Selection of Hazards

A comprehensive list of potential hazards was used as a checklist of disasters that occur or might occur in Chester County. Each hazard was analyzed and rated with regard to the frequency of past occurrences in the county. Natural and man-created disasters were then reviewed to determine which were more likely to recur in analyzed in the county. The following hazards were selected and analyzed in this report: 1. Natural Hazards a. Floods b. Winter Storms c. Tornadoes, Hurricanes and Windstorms d. Drought and Water Supply Deficiencies e. Earthquakes 2. Man–Caused Hazards a. Dam Failures b. Hazardous Materials c. Fire Hazards d. Transportation Accidents e. Energy Emergencies f. Civil Disorders g. Fixed Nuclear Facilities h. Nuclear Attack


3 July 2009

II. COUNTY PROFILE

A. General Information

Much of Chester County's 760 square mile area exists today as it did in 1682 when William Penn's colonists cleared woodlands for farming. However, while most of the land in the county is still used for agriculture, the county’s economy is based primarily in the wholesale trade (35% in 2002), followed by retail trade and manufacturing (26% and 15%), respectively (Figure 1 and Table 1). Over 5,000 acres of open space comprise a growing park system preserving the natural, historical and cultural characteristics of the county (Figure 2 and Table 2). The system currently includes Hibernia Park, Nottingham Park, Warwick Park, Springton Manor, and Black Rock Sanctuary, as well as two hiking and biking trails (Struble and Chester Valley). In addition, Chester County is home to five state parks. Marsh Creek State Park covers 1,700 acres with a 535 acre lake, and it is located in north-central Chester County. Located several miles northwest of Marsh Creek is French Creek State Park which is shared by Berks County. Brandywine Battlefield State Park, White Clay Park Preserve and State Gamelands #43 are also located in part or entirety in Chester County. Valley Forge National Historical Park lies on the boundary of Chester and Montgomery Counties. The National Park Service assumed ownership of Valley Forge in 1977, and several improvements have been made since then to inform visitors of the significance of this Revolutionary War site. Hopewell Village National Historical Site straddles the boundary between Chester and Berks Counties. The village has been restored by the National Park Service to the way it appeared between 1820 and 1840. The rich cultural heritage of the county is apparent by the large number of cultural groups and organizations throughout the area. Among these offerings are the Kennett Symphony Orchestra, Chester County Historical Society and Museum, and People's Light and Theatre Company. The Hadley Foundation sponsors free national and international speakers and programs in the Kennett area. The Brandywine River Museum, with its collection of Andrew Wyeth and N.C. Wyeth paintings, is located in Delaware County along the Chester County border. Chester County is a favorite destination of many tourists who travel the eastern United States. One of the most beautiful and famous horticultural sites in the nation is Longwood gardens. The gardens, a short distance from the Brandywine Battlefield, were an underground railway stop and gathering place for many runaway slaves prior to the Civil War. The gardens now offer about 340 acres of incredible indoor and outdoor beauty year round. Horticultural displays are also found at Swiss Pines and Star Rose Gardens. Several villages in Chester County represent architectural periods of the past and interesting farm buildings and covered bridges dot the countryside. Chester County is also well known for its fox hunting and beautiful scenery. Chester County has seen a recent influx of retail centers (Figure 3 and Table 3), business


4 July 2009

parks (Figure 4 and table 4), and industrial parks. These centers are particularly located in the eastern and central parts of the county, in areas that are easily accessible to major highways and interstates. Housing of all types and sizes has followed employment in Chester County (Table 5 and Figure 5). Fourteen school districts, a large number of private schools and seven higher education facilities – including West Chester University, Lincoln University, Penn State Great Valley, Valley Forge Christian College and Immaculata College – offer Chester County residents vast educational opportunities. Most of the highly developed areas of Chester County are served by public water systems. This includes service in all of the boroughs and the City of Coatesville. Less densely-populated sections, particularly in the western and southern portions of the county, rely on on-site well water. County government, located at the county seat in West Chester, is administered by a three-person Board of Commissioners. Services available to residents include the court and library systems, a county prison and county home for the aged, and a host of human services. Each of the 73 municipalities (Figure 6) is governed by an elected body consisting of supervisors, councils, or commissioners, depending on the municipal designation. Each is responsible for establishing and administering municipal financial budgets and tax rates, as well as being responsible for land use controls through zoning, subdivision regulations, and building permits. Road maintenance and other general services are provided by local officials as well.

B. Interesting Highlights

The information found below is a composite of facts and statistics taken from the 2002 Chester County Profile, Chester County Planning Commission (CCPC) Census 2000 Briefs, CCPC Planning Data Sheets, 2000 Census Data, and 2002 Agricultural Census Data.

- Of Pennsylvania’s 67 counties, Chester County ranks 28th in area (761.3 square

miles). - There are 26 miles of Turnpike, 1,050 miles of state federal highways and 2,386

miles of secondary and municipal roads in Chester County. - There are seven higher education facilities within Chester County. West Chester

University, including its Exton Campus, is the largest with over 12,800 total students. - Five daily newspapers and five weekly newspapers serve the county.


5 July 2009

- The median household income in Chester County during the 2000 Census was $65,295 and the median family income was $76,916, making Chester County the wealthiest county in the state (Figure 7).

- Chester County was ranked first in the State in the 2002 Agricultural Census for the

total value of crops ($288,093,000) and second in the state in the total value of agricultural products sold ($376,771,000).

- As of 2006, 43 municipalities in Chester County had curbside recycling programs, 28

had public wastewater services and 16 had public water systems.

- There are 21 federal, state, and county parks, preserves, recreational areas and trails totaling over 11,000 acres and 63 miles in Chester County. Approximately 15 percent of the land in Chester County is protected open space.

- Chester County has the highest educated population in the state with 89% of adults

having graduated from high school and 42% having graduated from college.

- Chester County has five general hospitals, one psychiatric hospital, one rehabilitation hospital, and one medical center. Most fire protection and ambulance service in the County is provided by volunteer fire companies and private ambulance services.

- Since Chester County was never under glacial ice, there is a lack of natural lakes and

U-shaped valleys. This results in more rounded and gentle topography than areas to the north.

- The population of the County continues to grow somewhat older. This reflects the

aging of the baby boomers (those born between 1946 and 1964) and an increase in the elderly population (Figure 8).

C. Physical Features

Chester County is located in southeastern Pennsylvania (Figure 9), west of the city of Philadelphia. In the broader regional context, Chester County is located in the major northeastern complex of metropolitan areas stretching from Boston to Washington, D.C. This corridor contains the largest concentration of population and jobs in the nation. Chester County is located within a few hours drive of New York City, Baltimore, and Washington, D.C. Chester County adjoins Lancaster, Berks, Montgomery, and Delaware Counties (Figure 10). Its southern boundary borders on the states of Delaware and Maryland. The Schuylkill River forms the county’s northern limits, while on the west it is partially bounded by the Octoraro Creek. The historic Brandywine Creek forms part of its eastern border. The Chester Valley extends from the northeast to the southwest through the center of the country, and contains some of the most productive and magnificent land in the commonwealth.


6 July 2009

Chester County is part of the Piedmont Province of the Appalachian Highlands. The area is characterized by gentle to steep rolling countryside (Figure 11). Ridges and valleys are also significant geographic features in Chester County. The Great Valley, which is the most notable ridge and valley feature, extends east-west across the center of the county. Elevations within the county range from 1,020 feet above sea level at Welsh Mountain in northwestern Chester County, to 66 feet above sea level where the Schuylkill River flows out of the county at Valley Forge National Park. The Schuylkill River and Brandywine Creek are the major streams in Chester County, draining over 60 percent of the county (Figure 12). The main streams flow to the southeast, following the natural slope of the land. The drainage pattern is closely spaced with many streams per square mile. Chester County is characterized by a humid continental climate that is modified by its proximity to both the Atlantic Ocean and the Appalachian Mountains. Summers are long and warm while winters are moderately cold. Temperatures range from an average of 33ºF in the winter to 75ºF in the summer. Precipitation averages about 45 inches per year including around 25 inches of snow.

D. History The county was founded in 1582 as one of the three original counties created by William Penn. The area was purchased from the Indians in several distinct deeds, making it the first to be purchased on the west side of the Schuylkill. After selling the land, the Indians were allowed to live there until the settlers gradually took over the county. When the Revolutionary War ended there were only four Indians living in the county. The last was “Indian Hannah" who died in the early 1800s. The first settlers in the county were Welsh Quakers (1583), followed by the Finns (1540), Dutch (1616), English (1634), and Swedes (1638). Chester County was named for Chestershire, England, the native soil of so many of its early settlers. During the Revolutionary War, Chester County was the site of several important events. Unable to stem the British advance on his positions, Washington lost the battle of Brandywine Creek on September 11, 1777, and on September 20th, "Mad" Anthony Wayne's troops were nearly wiped out in the "Paoli Massacre" at Malvern. It was just a few months later that the Continental Army's critical winter ordeal began at Valley Forge. In 1789, Chester County lost its direct link to a seaport when Delaware County was created from the southeast portion of its territory. When the original county seat of Chester was included in Delaware County, the municipality of "Turk's Head" became West Chester and was incorporated as a borough on March 28, 1799.


7 July 2009

Early on, the predominant sector of the economy was agricultural since the country’s soils were very conductive to farming activities. The discovery of rich mineral deposits led to the establishment of the first county iron works at French Creek in 1718. The first rolling mill in America was built at Coatesville in 1793, and iron remains an important industry to the present day. The largest plate mill in the nation still operates in Coatesville, Chester County's only City. After the establishment of the iron industry, more businesses and industries followed to meet the needs of an increasing population. Chester County continued to grow and progress into the 20th century. Farming and industry continued to prosper while the economy gradually became more financial, trade, and service oriented. Today the county offers an environment that is suitable for a variety of economic activities. “High tech” firms, as well as agriculture and manufacturing, coexist in surroundings that are suitable for all.

E. Current Land Use

The existing land use pattern reflects continued suburban expansion from Philadelphia into eastern Chester County. This development includes non-residential, as well as residential uses, making this area of the county more urban in character. Elsewhere in Chester County, the pattern reflects the continued spread of primarily residential development into rural areas, making them more suburban in character. The most intensive development is located in eastern Chester County along Route 30 through the Chester Valley, which extends east and west through the middle of the county (Figure 13). Existing land use in Chester County is summarized in Table 6. The largest category is agriculture with over 190,000 acres. Woodlands are the second largest category with over 130,000 acres. Residential land accounts for nearly 85,000 acres, which is double the amount of residential land in 1970 (Figure 14). Commercial land uses occupy approximately 8,100 acres, just over 1.5% of the total land area. These uses are concentrated in the urban centers (Coatesville City and the boroughs) and along the major highways. In addition to the retail trade, this land use category includes office parks. Office parks are large employment centers near major highways, primarily Route 202. Industrial land use occupies approximately 2,800 acres, about 1% of the total land area. This category includes manufacturing uses which are located primarily in established urban centers, such as Coatesville, Downing town, West Chester, and Phoenixville. It also includes light industrial uses, such as assembly, warehouses, and research and development, which are primarily located in industrial parks near major highways. The largest concentrations are near Route 202 and Route 30.


8 July 2009

F. Census Designated Places

Census designated places (CDPs) are densely settled concentrations of population that are identifiable by name, but are not legally incorporated places. Typically, these communities have developed as recognized places over the years from small commercial areas or market centers. Since these places are recognized by the local population, it is important to delineate them as distinct areas for the Census of Population and Housing. CDPs are delineated for the decennial census as the statistical counterparts of incorporated places. Their boundaries usually coincide with visible features (i.e. roads, watercourses, etc.) or the boundary of an adjacent incorporated place. They have no legal status; nor do these places have officials elected to serve traditional municipal functions. CDP boundaries may change with changes in the settlement pattern. A CDP with the same name as in previous censuses does not necessarily have the same boundaries. To qualify as a CDP for the 2000 Census, an unincorporated community must have 1,000 or more persons if outside the boundaries of an urbanized area delineated for the 1990 Census. If it is within an urbanized area delineated for the 1990 census, the community must have 2,500 or more persons. For the 2000 Census, a total of ten CDPs were identified for Chester County. The general areas of these communities are shown in Figure 15.

G. Municipality-Level Population Projections (Year 2030)

Background

A summary of various population statistics for Chester County, in comparison with other counties in southeastern Pennsylvania, is presented in Table 7. The Chester County Planning Commission has prepared population projections to the year 2030. For the years 2010, 2020, and 2030 the projected populations are 483,500, 528,000, and 571,800 respectively for Chester County. These projections were developed by using data obtained from a research group at Pennsylvania State University, the Delaware Valley Regional Planning Commission, and the 2000 U.S. Census Data. The methodology utilized was the cohort-component method which uses the three processes of population change: births, deaths, and migration.

However, projecting population for municipalities involved a separate process than projecting the County population. Since the cohort-component method of projecting population involved a number of variables not available on the municipal level and since most municipalities do not have a large population base to work with, a different approach to municipal projections was carried out.


9 July 2009

Methodology Determining projections for municipalities in Chester County was a two-step process. The first step involved the calculation of unadjusted figures through use of the Bureau of the Census ratio-shared method. This method involved computing the average ratio of a municipality's population to the total County population in previous Census years. Further, a 2000 population for each municipality was calculated using the average ratio shared method from 1950, 1970, 1980, and 1990. These numbers were then compared with actual 2000 Census figures (Table 8) and a percent difference between these two was calculated. For projections, the numbers calculated using the average ratio-shared method were multiplied by the percent difference in order to determine the unadjusted population projections for each municipality. The second step of this process involved adjustment to these projections by looking at a number of variables for each municipality. These variables included past population trends, existing land use, known development proposals, transportation access, and other factors that could affect population change. Unlike the previous step this one does not contain calculations but includes general determinations about a municipality's future. The results of this process are shown in Table 9.


10 July 2009

Figures and Tables Section II


11 July 2009

Figure 1. Comparison of 1995 and 2000 Employment Sectors in

Chester County and Surrounding Region


12 July 2009

Table 1. Number of Business Establishments in Chester County

Industry Type (NAICS) 2003 2004 2005 2006 Total 13,197 13,383 13,713 13,827 Forestry, fishing, hunting, and agriculture support 48 44 49 47 Mining 8 9 9 9 Utilities 25 24 27 21 Construction 1,394 1,447 1,493 1,468 Manufacturing 616 602 599 576 Wholesale trade 990 991 1,002 987 Retail trade 1,552 1,560 1,548 1,525 Transportation & warehousing 228 237 244 249 Information 299 288 316 299 Finance & insurance 989 984 975 1,043 Real estate & rental & leasing 429 445 464 464 Professional, scientific & technical services 2,141 2,161 2,213 2,289 Management of companies & enterprises 143 132 218 198 Admin, support, waste mgt, remediation services 798 801 836 868 Educational services 171 174 181 178 Health care and social assistance 1,168 1,235 1,271 1,313 Arts, entertainment & recreation 190 194 198 204 Accommodation & food services 799 814 832 858 Other services (except public administration) 1,180 1,195 1,218 1,208 Unclassified establishments 29 46 20 23 Note: Does not include government. NAICS – North American Industry Classification System Source: County Business Patterns, U.S. Census Bureau


13 July 2009

Figure 2.


14 July 2009

Table 2. Chester County Open Space and Recreation Areas

Source: Chester County Planning Commission, 2003


15 July 2009

Figure 3.


16 July 2009

Table 3. Major Retail Centers in Chester County

Source: Chester County Tax Assessment Office, 2000


17 July 2009

Figure 4.


18 July 2009

Table 4. Major Business Parks in Chester County



19 July 2009

Table 5. Total Housing Units in Chester County

Year Total Units Number Change Percent Change 1930 29,655 NA* NA* 1940 33,046 3,391 11.4 1950 42,143 9,097 27.5 1960 58,974 16,831 39.9 1970 80,457 21,483 36.4 1980 110,183 29,726 36.9 1990 139,597 29,414 26.7 2000 163,773 24,176 17.3 2005 178,778 15,005 9.2

Note: *Not Available Source: U.S. Census Bureau, Census 2000


20 July 2009

Figure 5.


21 July 2009

Figure 6.


22 July 2009

Figure 7.


23 July 2009

Figure 8. Population Pyramids by Age Group


24 July 2009

Figure 9.


25 July 2009

Figure 10.


26 July 2009

Figure 11.


27 July 2009

Figure 12.


28 July 2009

Table 6. Existing Land Use in Chester County

Land use Acres % of County Residential 84,099 17.3 Commercial 8,110 1.7 Industrial 2,791 0.6 Community Service 4,506 0.9 Transportation & Utilities 37,406 7.7 Mining 1,203 0.2 Agriculture 190,250 39.1 Recreation 7,552 1.6 Woodlands 133,565 27.5 Water Bodies 4,573 0.9 Other/Vacant 12,010 2.5



29 July 2009

Figure 13.


30 July 2009

Figure 14.


31 July 2009

Figure 15.


32 July 2009

Table 7. Southeastern Pennsylvania County Comparisons

COUNTY COUNTY CLASS

POPULATION 2000 1990 1980 1970 1960

Chester Third 433,501 376,396 316,660 277,746 210,608 Berks Third 373,638 336,523 312,509 296,382 275,414 Bucks Third 597,635 541,174 479,180 416,728 308,567 Delaware Second A 550,864 547,651 555,023 603,456 553,154 Lancaster Third 470,658 422,822 362,346 320,079 319,693 Montgomery Second A 750,097 678,111 643,377 624,080 516,682 Philadelphia First 1,517,550 1,585,577 1,688,210 1,949,966 2,002,512 York Third 381,751 339,574 312,961 272,603 238,336

COUNTY PERCENT CHANGE (%) 1990-2000 1980-1990 1970-1980 1960-1970 1960-2000

Chester 15.20 18.90 14.00 31.90 105.83 Berks 11.00 7.70 5.40 7.60 35.70 Bucks 10.40 12.90 15.00 35.10 93.70 Delaware 0.60 -1.30 -8.00 9.10 -0.40 Lancaster 11.30 16.70 13.20 0.10 47.20 Montgomery 10.60 5.40 3.10 20.80 45.20 Philadelphia -4.30 -6.10 -13.40 -2.60 -24.20 York 12.40 8.50 14.80 14.40 60.20

COUNTY PERCENT (%) NO. & PERCENT (%) MEDIAN AGE MALE FEMALE AGE 0-17 AGE 18-64 AGE 65+

Chester 49.1 50.9 113,582 - 26.2 269,242 - 62.1 50,677 - 11.7 50.9 Berks 49.0 51.0 91,909 - 24.6 225,539 - 60.4 56,190 - 15.0 51.0 Bucks 49.1 50.9 153,486 - 25.7 370,055 - 61.9 74,094 - 12.4 50.9 Delaware 47.7 52.3 136,833 - 24.8 328,362 - 59.6 85,669 - 15.5 52.3 Lancaster 48.8 51.2 125,291 - 26.6 279,307 - 59.3 66,060 - 14.0 51.2 Montgomery 48.3 51.7 181,145 - 24.1 456,973 - 60.9 111,797 - 14.9 51.7 Philadelphia 46.5 53.5 383,469 - 25.3 920,359 - 60.6 213,722 - 14.1 53.5 York 49.2 50.8 93,983 - 24.6 236,276 - 61.9 51,492 - 13.5 50.8

COUNTY NO. & PERCENT ETHNICITY (%) LABOR

FORCE (1,000’S)

NO & % UNEMPLOYMENT

RATE WHITE BLACK OTHER

Chester 386,745 - 89.2 27,040 - 6.2 19,716 - 4.5 221.3 8,200 – 2.5 Berks 329,460 - 88.2 13,778 - 3.7 30,400 - 8.1 180.8 9,700 – 5.1 Bucks 552,588 - 92.5 19,495 - 3.3 255,552 - 4.3 308.3 11,100 – 3.5 Delaware 442,449 - 80.3 79,981 - 14.5 28,434 - 5.2 258.8 13,300 – 4.9 Lancaster 430,456 - 91.5 12,993 - 2.8 27,209 - 5.8 235.7 7,300 – 3.0 Montgomery 648,510 - 86.5 55,969 - 7.5 45,618 - 6.1 384.7 18,000 – 4.5 Philadelphia 683,267 - 45.0 655,824 - 43.2 178,459 - 11.8 585.0 71,600 – 10.9 York 354,103 - 92.8 14,095 - 3.7 13,553 - 3.6 196.0 7,300 – 3.6


33 July 2009

Table 7. Southeastern Pennsylvania County Comparisons (cont.)

COUNTY SQ. MILES 2000 POP. DENSITY

2ND CLASS TWPS.

1ST CLASS TWPS. BOROS. 3RD CLASS

CITIES

Chester 756 573.4 56 1 15 1 Berks 859 435.0 40 2 31 1 Bucks 607 984.0 10 21 22 0 Delaware 184 2,990.4 2 19 27 1 Lancaster 949 495.9 40 1 18 1 Montgomery 483 1,552.6 7 31 24 0 Philadelphia 135 11,233.6 0 0 0 0 York 904 422.1 33 2 36 1

COUNTY SCHOOL DISTS.

IND. DEV. AUTH. (1990)

COUNTYWIDE AUTH. (1990)

3 LARGEST MUNICIPALITIES

HOME RULE CHARTERS

(1990)

Chester 12 2 61 Tredyffrin – 29,062 W. Goshen – 20,495 W. Chester – 17,722

Coatesville Elk

Tredyffrin

Berks 18 1 98 Reading – 81,207 Spring – 22,600 Exeter – 21,161

None

Bucks 13 5 81 Bristol – 55,521

Bensalem – 58,434 Middletown – 44,141

Chalfont

Delaware 15 1 63

Upper Darby – 81,821 Haverford – 48,498

Chester – 37,017

Delaware Chester (City)

Haverford, Middletown,

Radnor, Upper Darby, Upper Providence

Lancaster 16 4 79 Lancaster – 55,351 Manheim – 33,697

E. Hempfield – 21,399 None

Montgomery 21 9 108

L. Merion – 59,850 Abington – 56,103

Cheltenham – 36,875

Bryn Athyn, Cheltenham,

Horsham, Plymouth

Philadelphia 1 1 4 Philadelphia – 1,479,339 Philadelphia

York 15 1 84

40,081York – Springettsbury –

23,883 York (Twp) – 21,637

None

Source: Chester County Planning Commission, U.S. census Bureau, Census 2000


34 July 2009

Table 8. Chester County Municipal Population Change

Geographic Area Census Population Estimates Change Change Percent Change

April 1, 2000 July 1, 2005 July 1, 2006 2005 -

2006 2000 -

2006 2000 -

2006 Chester County 433,501 473,723 482,112 8,389 48,611 11.2%

Atglen Boro 1,217 1,347 1,357 10 140 11.5% Avondale Boro 1,108 1,093 1,093 0 -15 -1.4% Birmingham Twp 4,221 4,258 4,268 10 47 1.1% Caln Twp 11,916 12,182 12,240 58 324 2.7% Charlestown Twp 4,051 5,948 6,221 273 2,170 53.6% Coatesville City 10,838 11,475 11,631 156 793 7.3% Downingtown Boro 7,589 7,845 7,885 40 296 3.9% East Bradford Twp 9,405 10,158 10,213 55 808 8.6% East Brandywine Twp 5,822 6,439 6,485 46 663 11.4% East Caln Twp 2,857 4,225 4,324 99 1,467 51.3% East Coventry Twp 4,566 5,688 5,996 308 1,430 31.3% East Fallowfield Twp 5,157 6,699 7,028 329 1,871 36.3% East Goshen Twp 16,824 17,817 17,884 67 1,060 6.3% East Marlborough Twp 6,317 7,738 7,955 217 1,638 25.9% East Nantmeal Twp 1,787 1,862 1,891 29 104 5.8% East Nottingham Twp 5,516 7,939 7,975 36 2,459 44.6% East Pikeland Twp 6,551 6,805 6,817 12 266 4.1% Easttown Twp 10,270 10,382 10,477 95 207 2.0% East Vincent Twp 5,493 6,435 6,451 16 958 17.4% East Whiteland Twp 9,333 10,428 10,466 38 1,133 12.1% Elk Twp 1,485 1,473 1,501 28 16 1.1% Elverson Boro 959 1,162 1,180 18 221 23.0% Franklin Twp 3,850 4,269 4,415 146 565 14.7% Highland Twp 1,125 1,194 1,200 6 75 6.7% Honey Brook Boro 1,287 1,385 1,439 54 152 11.8% Honey Brook Twp 6,278 6,815 7,030 215 752 12.0% Kennett Twp 6,451 7,219 7,403 184 952 14.8% Kennett Square Boro 5,273 5,282 5,292 10 19 0.4% London Britain Twp 2,797 3,008 3,092 84 295 10.5% Londonderry Twp 1,632 1,843 1,859 16 227 13.9% London Grove Twp 5,265 6,237 6,487 250 1,222 23.2% Lower Oxford Twp 4,319 5,021 5,047 26 728 16.9% Malvern Boro 3,059 3,094 3,108 14 49 1.6% Modena Boro 610 601 602 1 -8 -1.3% New Garden Twp 9,083 11,004 11,348 344 2,265 24.9%


35 July 2009

Geographic Area Census Population Estimates Change Change Percent Change

April 1, 2000 July 1, 2005 July 1, 2006 2005 -

2006 2000 -

2006 2000 -

2006 Newlin Twp 1,150 1,236 1,262 26 112 9.7% New London Twp 4,583 5,472 5,622 150 1,039 22.7% North Coventry Twp 7,381 7,602 7,662 60 281 3.8% Oxford Boro 4,315 4,674 4,686 12 371 8.6% Parkesburg Boro 3,373 3,439 3,445 6 72 2.1% Penn Twp 2,812 4,700 5,254 554 2,442 86.8% Pennsbury Twp 3,500 3,903 3,910 7 410 11.7% Phoenixville Boro 14,788 15,392 15,811 419 1,023 6.9% Pocopson Twp 3,350 3,367 3,371 4 21 0.6% Sadsbury Twp 2,582 3,231 3,321 90 739 28.6% Schuylkill Twp 6,960 7,609 7,682 73 722 10.4% South Coatesville Boro 997 1,061 1,065 4 68 6.8% South Coventry Twp 1,895 2,381 2,524 143 629 33.2% Spring City Boro 3,305 3,278 3,397 119 92 2.8% Thornbury Twp 2,678 2,927 2,939 12 261 9.7% Tredyffrin Twp 29,062 28,929 29,014 85 -48 -0.2% Upper Oxford Twp 2,095 2,367 2,386 19 291 13.9% Upper Uwchlan Twp 6,850 8,037 9,549 1,512 2,699 39.4% Uwchlan Twp 16,576 18,283 18,430 147 1,854 11.2% Valley Twp 5,116 6,033 6,265 232 1,149 22.5% Wallace Twp 3,240 3,396 3,433 37 193 6.0% Warwick Twp 2,556 2,690 2,719 29 163 6.4% West Bradford Twp 10,775 11,673 12,146 473 1,371 12.7% West Brandywine Twp 7,153 7,624 7,683 59 530 7.4% West Caln Twp 7,054 7,795 8,085 290 1,031 14.6% West Chester Boro 17,861 18,204 18,224 20 363 2.0% West Fallowfield Twp 2,485 2,588 2,599 11 114 4.6% West Goshen Twp 20,495 21,138 21,168 30 673 3.3% West Grove Boro 2,652 2,635 2,705 70 53 2.0% West Marlborough Twp 859 868 869 1 10 1.2% West Nantmeal Twp 2,031 2,190 2,222 32 191 9.4% West Nottingham Twp 2,634 2,751 2,780 29 146 5.5% West Pikeland Twp 3,551 3,982 4,042 60 491 13.8% West Sadsbury Twp 2,444 2,495 2,504 9 60 2.5% Westtown Twp 10,352 10,589 10,649 60 297 2.9% West Vincent Twp 3,170 3,879 4,040 161 870 27.4% West Whiteland Twp 16,499 18,212 18,235 23 1,736 10.5% Willistown Twp 10,011 10,723 10,754 31 743 7.4%


36 July 2009

Table 9. Chester County Municipal Population Projections

1990

Census 2000

Census 2005

Estimate 2010

Forecast 2015

Forecast 2020

Forecast 2025

Forecast 2030

Forecast 2035

Forecast

Absolute Change 2005 -

2035

Percent Change 2005 -

2035 Chester County 376,396 433,512 473,880 505,095 531,971 557,623 582,047 605,271 622,498 148,618 31%

Atglen Boro 825 1,215 1,350 1,443 1,531 1,614 1,692 1,766 1,835 485 36% Avondale Boro 954 1,110 1,095 1,149 1,294 1,432 1,564 1,690 1,778 683 62% Birmingham Twp 2,636 4,220 4,264 4,601 4,822 5,033 5,235 5,427 5,562 1,298 30% Caln Twp 11,997 11,916 12,270 13,166 14,013 14,815 15,569 16,282 16,939 4,669 38% Charlestown Twp 1,876 4,050 5,824 6,327 6,929 7,505 8,054 8,578 8,944 3,120 54% Coatesville City 11,038 10,838 11,491 12,238 12,662 13,067 13,454 13,823 14,081 2,590 23% Downingtown Boro 7,749 7,590 7,856 8,143 8,531 8,902 9,256 9,594 9,830 1,974 25% East Bradford Twp 6,440 9,405 10,172 10,940 11,528 12,091 12,628 13,140 13,498 3,326 33% East Brandywine Twp 5,179 5,825 6,449 7,527 7,963 8,379 8,777 9,156 9,421 2,972 46% East Caln Twp 2,619 2,855 4,131 4,471 4,681 4,882 5,074 5,256 5,384 1,253 30% East Coventry Twp 4,450 4,565 5,696 6,196 6,625 7,035 7,427 7,800 8,061 2,365 42% East Fallowfield Twp 4,433 5,160 6,709 7,143 7,554 7,943 8,309 8,655 8,973 2,264 34% East Goshen Twp 15,138 16,825 17,843 18,749 19,605 20,415 21,178 21,899 22,563 4,720 26% East Marlborough Twp 4,781 6,315 7,750 8,649 9,165 9,658 10,129 10,578 10,892 3,142 41% East Nantmeal Twp 1,448 1,785 1,864 1,971 2,029 2,084 2,137 2,187 2,222 358 19% East Nottingham Twp 3,841 5,515 7,951 8,963 9,704 10,413 11,090 11,734 12,185 4,234 53% East Pikeland Twp 5,825 6,550 6,816 7,374 7,905 8,414 8,899 9,361 9,684 2,868 42% Easttown Twp 9,570 10,265 10,397 10,630 11,078 11,506 11,915 12,304 12,577 2,180 21% East Vincent Twp 4,161 5,493 6,444 6,920 7,496 8,047 8,573 9,074 9,425 2,981 46% East Whiteland Twp 8,398 9,335 10,302 10,757 11,313 11,844 12,352 12,835 13,173 2,871 28% Elk Twp 1,129 1,490 1,476 1,558 1,636 1,710 1,779 1,845 1,905 429 29% Elverson Boro 470 960 1,164 1,322 1,521 1,711 1,892 2,065 2,186 1,022 88% Franklin Twp 2,779 3,850 4,276 4,832 5,186 5,525 5,848 6,156 6,372 2,096 49% Highland Twp 1,199 1,125 1,196 1,240 1,282 1,321 1,358 1,393 1,425 229 19% Honey Brook Boro 1,184 1,285 1,388 1,449 1,554 1,655 1,751 1,843 1,907 519 37% Honey Brook Twp 5,449 6,280 6,824 7,219 7,593 7,946 8,279 8,593 8,883 2,059 30% Kennett Twp 4,624 6,450 7,229 7,907 8,333 8,741 9,131 9,501 9,761 2,532 35% Kennett Square Boro 5,218 5,275 5,290 5,418 5,588 5,750 5,904 6,052 6,155 865 16% London Britain Twp 2,671 2,795 3,013 3,208 3,282 3,353 3,421 3,485 3,530 517 17%


37 July 2009

1990

Census 2000

Census 2005

Estimate 2010

Forecast 2015

Forecast 2020

Forecast 2025

Forecast 2030

Forecast 2035

Forecast


2035


2035 Londonderry Twp 1,243 1,630 1,845 2,226 2,401 2,569 2,730 2,882 2,989 1,144 62% London Grove Twp 3,922 5,265 6,246 7,141 7,768 8,367 8,940 9,485 9,866 3,620 58% Lower Oxford Twp 3,264 4,320 4,907 5,420 5,905 6,364 6,797 7,205 7,581 2,674 54% Malvern Boro 2,944 3,060 3,099 3,157 3,260 3,358 3,451 3,541 3,603 504 16% Modena Boro 563 610 602 613 669 723 775 824 858 256 43% New Garden Twp 5,430 9,080 11,020 12,152 13,019 13,848 14,640 15,393 15,921 4,901 44% Newlin Twp 1,092 1,150 1,239 1,304 1,366 1,424 1,479 1,531 1,579 340 27% New London Twp 2,721 4,585 5,480 6,315 6,894 7,449 7,978 8,481 8,834 3,354 61% North Coventry Twp 7,506 7,380 7,614 7,795 7,967 8,129 8,282 8,426 8,559 945 12% Oxford Boro 3,769 4,315 4,681 4,924 5,153 5,370 5,574 5,767 5,945 1,264 27% Parkesburg Boro 2,981 3,375 3,444 3,643 3,951 4,246 4,527 4,795 4,983 1,539 45% Penn Twp 2,257 2,810 4,607 5,248 5,744 6,219 6,672 7,104 7,406 2,799 61% Pennsbury Twp 3,326 3,505 3,863 4,083 4,181 4,274 4,364 4,449 4,508 645 17% Phoenixville Boro 15,066 14,795 15,415 15,879 16,323 16,748 17,153 17,540 17,810 2,395 16% Pocopson Twp 3,266 3,350 3,371 3,719 3,936 4,143 4,341 4,530 4,662 1,291 38% Sadsbury Twp 2,510 2,580 3,236 3,629 3,885 4,130 4,364 4,587 4,743 1,507 47% Schuylkill Twp 6,416 6,965 7,637 8,208 8,748 9,258 9,739 10,193 10,612 2,975 39% South Coatesville Boro 1,026 995 1,062 1,100 1,183 1,262 1,338 1,410 1,460 398 37% South Coventry Twp 1,682 1,895 2,384 2,497 2,603 2,704 2,799 2,888 2,971 587 25% Spring City Boro 3,433 3,305 3,283 3,346 3,522 3,690 3,851 4,004 4,111 828 25% Thornbury Twp 1,131 2,678 2,931 3,230 3,405 3,572 3,732 3,884 3,990 1,059 36% Tredyffrin Twp 28,028 29,065 29,073 29,514 30,265 30,983 31,668 32,321 32,778 3,705 13% Upper Oxford Twp 1,615 2,095 2,370 2,631 2,723 2,810 2,894 2,973 3,029 659 28% Upper Uwchlan Twp 4,396 6,850 8,050 9,540 10,754 11,915 13,023 14,078 14,817 6,767 84% Uwchlan Twp 12,999 16,575 18,311 19,194 20,151 21,066 21,940 22,772 23,354 5,043 28% Valley Twp 4,007 5,115 6,042 6,498 7,054 7,587 8,095 8,578 8,917 2,875 48% Wallace Twp 2,541 3,240 3,401 3,699 4,033 4,353 4,658 4,949 5,152 1,751 51% Warwick Twp 2,575 2,555 2,694 2,747 2,797 2,845 2,889 2,932 2,971 277 10% West Bradford Twp 10,406 10,775 11,689 12,521 13,202 13,853 14,475 15,067 15,481 3,792 32% West Brandywine Twp 5,984 7,160 7,636 8,515 9,357 10,162 10,930 11,662 12,174 4,538 59% West Caln Twp 6,143 7,055 7,807 8,319 8,803 9,261 9,693 10,100 10,475 2,668 34% West Chester Boro 18,041 17,861 18,039 18,502 18,826 19,136 19,431 19,713 19,910 1,871 10%


38 July 2009

1990

Census 2000

Census 2005

Estimate 2010

Forecast 2015

Forecast 2020

Forecast 2025

Forecast 2030

Forecast 2035

Forecast


2035


2035 West Fallowfield Twp 2,342 2,485 2,592 2,675 2,753 2,826 2,896 2,962 3,022 430 17% West Goshen Twp 18,082 20,495 21,169 22,176 23,037 23,860 24,646 25,394 25,918 4,749 22% West Grove Boro 2,128 2,650 2,639 2,790 2,932 3,067 3,194 3,314 3,424 785 30% West Marlborough Twp 874 855 869 877 885 893 900 906 912 43 5% West Nantmeal Twp 1,958 2,030 2,193 2,261 2,373 2,480 2,582 2,679 2,747 554 25% West Nottingham Twp 2,183 2,634 2,755 2,858 3,073 3,278 3,474 3,660 3,791 1,036 38% West Pikeland Twp 2,323 3,550 3,988 4,501 4,768 5,023 5,267 5,499 5,662 1,674 42% West Sadsbury Twp 2,160 2,440 2,499 2,664 2,820 2,968 3,107 3,239 3,360 861 34% Westtown Twp 9,937 10,352 10,605 10,861 11,224 11,572 11,903 12,219 12,440 1,835 17% West Vincent Twp 2,262 3,170 3,885 4,203 4,396 4,581 4,758 4,926 5,044 1,159 30% West Whiteland Twp 12,403 16,500 18,339 19,296 20,109 20,886 21,628 22,334 22,829 4,490 24% Willistown Twp 9,380 10,015 10,739 11,114 11,352 11,580 11,797 12,004 12,149 1,410 13%


39 July 2009

III. NATURAL HAZARDS

A. Floods

Flooding is the most prevalent natural disaster occurring in the Commonwealth of Pennsylvania. Floods cause over $1 billion worth of property damage annually. It is important for emergency management personnel to analyze floodplains and other critical areas in the county and determine how vulnerable to flooding the community might be. Approximately 80 percent of Chester County is located in the Lower Delaware River Basin (Figure 16) as designated by the State Water Plan. This basin is located in southeastern Pennsylvania, and includes all of Philadelphia and Delaware Counties, most of Chester, Montgomery and Berks Counties, the southeast half of Schuylkill County, and small segments of Carbon, Lehigh, Bucks, Lancaster and Lebanon Counties. Overall, the drainage of the Lower Delaware covers 2,708 square miles or approximately 42 percent of the Pennsylvania portion of the Delaware River Basin. Flooding in this basin has been a result of extensive development in floodplain areas. The remainder of Chester County is located in the Susquehanna River Basin (Figure 17). This basin is represented mainly by the Octorara Watershed which has been subject to less developmental pressure. Figure 18 depicts all watersheds in Chester County. History Chester County has been affected by flooding relatively frequently in the past. Table 10 lists the significant flooding events that have been recorded since 1971. Specific areas where flooding has caused problems in the past are those locations abutting the Schuylkill and Brandywine Rivers, as well as several creeks (e.g. White Clay, French, Octorara, Red Clay and Elk). Vulnerability/Maximum Threat Seventy-one of 73 municipalities in Chester County are flood-prone; however, compared with many parts of the south, intense flood-producing rainfalls in the county occur only occasionally and are most commonly a product of summer thunderstorms or early fall hurricanes. Due to the rolling landscape and low water capacity of the soils and underlying rocks, flooding due to runoff from a heavy rainfall may be more severe in a stream valley. Fortunately, the flooding tendency in streets, etc., may be less severe due to slopes and resulting rapid runoff to streams. Floods may occur during any month of the year, although they occur with greater frequency in the spring months of March and April due to a combination of rainfall and snowmelt. In addition to local flooding from severe thunderstorms during the summer and fall, storms of tropical origin sometimes deposit flood-producing rains.


40 July 2009

Probability Within the flood susceptible areas of Chester County, it is expected that the character of flooding will remain essentially unchanged over the coming years. Protection against flood damage and loss can be greatly decreased by monitoring weather patterns, forecasts, stream and rain gauges (Figure 19), and historical statistics (Tables 11, 12, and 13). In addition to analysis of this data, attention must be paid to floodplain areas, and types and consistencies of soils.

The map of Chester County in Figure 20 shows the Flood Hazard Areas in Chester County. Alluvial soils that are subject to regular flooding, and the perennially wet soils that are subject to occasional flooding, as well as being generally too wet for most building and agricultural purposes. Presently, all but one of Chester County's 73 municipalities have floodplain zoning. Floodplain Zoning is not necessary in Oxford Borough, because it does not contain a flood plain. In addition, 66 of Chester County’s municipalities participate in the National Flood Insurance Program.

B. Winter Storms

Winter storms occur on the average of five times a year in Pennsylvania. Every county in the Commonwealth is subject to severe winter storms, although the northern tier, western counties and mountainous regions tend to experience these storms more frequently and with greater severity. Pennsylvania experiences all levels of winter storms: ice storms, freezing rain, heavy snow, blizzards, and severe blizzards. More often than not energy sources have been interrupted and travel conditions have been treacherous by these storms. Severe situations have caused inconvenience and even danger to large portions of the state's population. History Chester County has experienced major winter storms of varying magnitudes. These storms have caused power failures and communication outages, loss of communication networks, road closings and stranded motorists requiring emergency transportation. Since 1950, the county has experienced numerous major winter storms as outlined in Table 14.

Vulnerability/Maximum Threat Snow, more so than sleet or freezing rain, accounts for a considerable portion of the colder season precipitation. Amounts usually total 20 to 30 inches per year; however, that much and more have occurred in individual months. Most of the snow occurs during December through March, although measurable amounts have been observed as early as mid-October and as late as mid-April. Although snowfall within the country varies from place to place, somewhat greater


41 July 2009

amounts are found in the northern and western sections, especially on the higher elevations. The ground is usually snow covered about one-quarter of the time during the winter season, with amounts of one inch or more covering the ground about 20-25 days annually. Measurable snow may be expected about 20 days per year. The lowest recorded seasonal amount since 1950 was only 2.1 inches during the winter of 1972-1973. The greatest amount recorded was 64.1 inches during the winter of 1995-1996. Probability It is reasonable to expect the number and severity of winter storms to remain fairly constant over a long period of time (see Tables 15, 16, and 17 for historical snow and temperature data). It is only through continuing public education and preparedness that future winter storms will be made less dangerous and more tolerable to the residents of Chester County.

C. Tornadoes, Hurricanes, and Wind Storms

Tornadoes and windstorms are common occurrences in the Commonwealth, especially during the spring and summer months. According to the National Climatic Data Center, 704 tornadoes have struck 62 of the Commonwealth's 67 counties between January 1950 and November 2007. Areas most prone to tornadoes and windstorms are the southeast, southwest, and northwest sections of the state. In regards to hurricanes, by the time most storms reach Pennsylvania they fail to satisfy the definition of a hurricane (75 mph winds). However, Chester County has been affected by the secondary effects (mainly heavy rainfall) of more than 20 hurricanes in the last 80 years. History/Vulnerability Chester County is included in the 14 Pennsylvania counties designated as areas of higher tornado frequency. There have been numerous occasions that tornado watches or warnings were issued, occasions resulting in high winds, rain, and/or hail. These tornadoes have created minor damage in the county with localized power failures lasting up to four hours. Since 1979, Chester County has experienced 25 major storms that caused more than $250,000 in property damage, deaths, or injuries. These storms are outlined in Table 18.

The most severe tropical storms/hurricanes occur in the Delaware River Basin. The worst storms occur when a hurricane joins a tropical storm on the coastline, forming a storm with two major storm centers. Such was the case during Hurricane Diane in August 1955. Although the county has not experienced hurricane force high winds, the rainfall from these storms has caused major flooding in the county.


42 July 2009

Probability The frequency of tornadoes and the effects of hurricanes and windstorms occurring in the county should remain fairly constant. Past experience has been that the winds of destructive force are generally produced by thunderstorms, as well as hurricanes and tornadoes. Wind velocities from any of these may reach in excess of 50 miles per hour but, with the exception of hurricanes or their remnants, relatively small areas of the county are affected at any one time. Destructive winds from thunderstorms sometimes occur, although destruction by fire caused by lightning is considered more frequent and costly. Tornado activity is unusual, but should not be discounted. June and July are the most likely months for tornado activity. Winds from hurricanes and tropical storms seldom reach destructive speeds in Chester County, although widespread minor damage sometimes results from a combination of heavy rain and fresh, strong winds. For the most part winds from such storms greatly diminish in intensity in their passage over land. According to the National Climatic Data Center, from 1916 through 2007, only 2 fatalities occurred in Chester County as a result of tornadoes. One fatality occurred in 1955, the other in 1979. Table 19 shows the frequency of tornadoes and number of resulting deaths in Pennsylvania, by month. Figure 21 shows the average annual number of tornadoes and related fatalities by state. Figure 22 and Tables 20 and 21 show relevant wind data for Chester County and the region.

D. Droughts and Water Supply Deficiencies

The two types of drought most common to Pennsylvania and of concern to emergency management are hydrologic drought and water management drought. Hydrologic drought entails a reduction of stream flows, a reduction in lake or reservoir storage and a lowering of groundwater levels. Hydrologic droughts are caused by a shift in weather patterns, resulting from below average precipitation. A water management drought exists when water management practices or facilities fail to bridge normal or abnormal dry periods. It is not necessarily a reduction in supply, but rather a disparity in supply and demand. History Chester County has been affected by eight drought emergencies since 1960, as outlined in Table 22. During drought periods, households experience low water pressure and conservation measures are usually implemented. Because of the rural nature of the county, agricultural areas can be greatly affected. Vulnerability/Maximum Threat There are 16 water purveyors, several homeowners associations and numerous private


43 July 2009

wells supplying the residents of Chester County (Figure 23). Primary water sources include the Octorara and Schuylkill Rivers, the east and west branches of the Brandywine Creek, and Pickering Creek. Currently, residents are not experiencing any water supply deficits, and no water suppliers are projected to face future water supply deficiencies. However, prolonged dry periods could adversely affect available water sources and cause drought situations. Chester County has experienced periods of abnormal precipitation in the past, the longest period having been five years. Probability Droughts and related water deficiencies should not significantly affect Chester County, so long as it does not experience lengthy inadequate rainfall periods. Also, quality monitoring and maintenance measures will hopefully decrease the possibility of any water management drought. The Chester County Groundwater Monitoring well network is depicted in Figure 24. Sample Groundwater Monitoring Well Status data is presented in Figure 25 and Table 23. Regardless of monitoring and maintenance measures, water conservation should become an everyday practice. The county, in cooperation with the water purveyors, completed a water supply planning effort in 1994, which was based on a 25 year water supply horizon.

E. Earthquakes

Pennsylvania is located in a seismic risk zone whereby minor and/or moderate earthquake damage may be expected. Although earthquakes in the Commonwealth are a rare occurrence (causing no injury or severe property damage), the crust of the earth is constantly shifting. Earthquakes do pose a possible threat that should be considered. History Chester County has three fault lines running through its boundaries. The Martic Line (a thrust fault) runs east to west, cutting across Route 100 just south of Route 30. The Huntingdon Valley Fault is located just below the Martic Line. The Rosemont Fault originates in Delaware County and arcs through the eastern portion of Chester County. None of these faults have been active in over 200 million years. The only sizeable earthquake activity Chester County has experienced is that of residual tremors felt as a result of an incident on April 22, 1984. The actual earthquake, centered in Lancaster County, measured 4 on the Richter Scale and IV in Mercalli intensity. The very minor tremors that are experienced by county residents usually occur (if at all), in the spring, wherein snow melt causes local stress buildup along fault areas.


44 July 2009

Vulnerability/Maximum Threat According to historical trends and the existence of faults, Chester County remains vulnerable to earthquake risk. The County lies in proximity to Philadelphia, where from 1980 to 1984 five minor earthquakes occurred, affecting Philadelphia City and the northern suburbs. Very little quake activity has occurred since 1984 with only three minor incidents happening in the region. Should the activity greatly intensify over the years, Chester County may be affected by residual tremors. A map of earthquake location in Pennsylvania is presented as Figure 26. Probability Earthquakes should continue to pose little threat to Chester County, with long intervals between any possible occurrences. The local stress buildup resulting from snowmelt is barely detectable, and is expected to continue on a very minor scale.


45 July 2009

Figures and Tables Section III


46 July 2009

Table 10. Significant Flood Events in Chester County

Date Property

Damage ($Mil) Disaster

Proclamations Notes Sept. 1971 N/A 1, 2 June 1972 N/A 1, 2 Tropical Storm Agnes June 1973 N/A N/A Flash Flood July 1973 N/A 2 Jan. 1978 N/A N/A Jan. 1979 N/A N/A Precautionary evacuation

along Schuylkill River Feb. 1979 N/A N/A July 1979 2.0 N/A Flash Flood Dec. 1983 N/A N/A Sept. 1985 N/A N/A Hurricane Gloria July 1989 N/A 3 April 1993 N/A N/A Jan. 1996 42.3 1, 2 Sept. 1999 3.0 1, 2 Hurricane Floyd Sept. 2003 3.5 1, 2 Hurricanes Isabel and

Henri Sept. 2004 N/A 1, 2 Tropical Depression

Ivan Sept. 2005 N/A 1 Hurricane Katrina June 2006 6.0 1, 2

Source: Pennsylvania Emergency Management Agency (PEMA), National Climatic Data Center (NCDC) Disaster Proclamations: (1) Governor’s Proclamation of Disaster Emergency (2) President’s Declaration of Major Disaster (3) Small Business Administration – Physical Disaster Loans and Economic Injury Disaster Loan


47 July 2009

Figure 16. Delaware River Basin


48 July 2009

Figure 17. Susquehanna River Basin


49 July 2009


50 July 2009

Figure 19.


51 July 2009

Table 11. Seasonal Precipitation Statistics1

Winter (Dec-Jan-Feb) Spring (March-April-May) Normal: approx. 9.5 Normal: approx. 10.5

Most Least Most Least 20.79 1978/79 4.18 1871/72 21.85 1983 5.21 1887 19.64 1914/15 4.76 1958/59 20.36 1980 6.08 1926 15.78 1948/49 4.86 1876/77 17.63 1947 6.13 1963 15.40 1977/78 5.04 1939/40 17.37 1912 6.15 1941 14.98 1901/02 5.40 1984/85 17.05 1933 6.37 1883 14.44 1902/03 5.57 1976/77 16.93 1953 13.92 1883/84 5.60 1954/55 16.16 1913

Summer (June-Jul-Aug) Fall (Sept-Oct-Nov) Normal: approx. 12.0 Normal: approx. 9.6

Most Least Most Least 22.93 1906 4.39 1966 17.84 1987 2.37 1922 21.39 1911 4.53 1964 17.14 1876 2.91 1879 21.30 1872 4.53 1894 16.38 1935 3.66 1915 20.68 1938 6.00 1983 16.18 1966 3.97 1941 19.32 1933 6.01 1881 15.22 1907 4.05 1884 6.40 1909 15.18 1889

1 All measurements in inches. Source: Pennsylvania State Climatologist, 2008


52 July 2009

Table 12. Monthly Precipitation Statistics

Most Least Inches Month Year Inches Month Year 9.58 January 1979 0.49 January 1981 5.5 February 1899 0.54 February 2002 7.11 March 1993 0.64 March 1910 8.56 April 19.83 0.83 April 1963 9.35 May 1989 0.92 May 1911 11.18 June 2006 0.60 June 1949 8.97 July 1969 1.06 July 1983 12.54 August 1955 1.05 August 1916 12.25 September 1999 0.58 September 1914 10.18 October 2005 0.09 October 1963 8.43 November 1972 0.04 November 1917 7.86 December 1983 0.25 December 1955

Source: Pennsylvania State Climatologist, 2008


53 July 2009

Table 13. Annual Precipitation Normal: approx. 41.4 inches

Most Least

Inches Year Inches Year 55.28 1873 29.31 1922 55.07 1989 39.34 1965 54.41 1983 29.88 1964 52.79 1979 30.21 1881 52.13 1975 31.01 1895 52.12 1947 32.15 1896 51.87 1906 32.18 1896 51.37 1933 32.20 1957 51.35 1911 32.27 1916 50.60 1889 32.40 1925



54 July 2009


55 July 2009

Table 14. Significant Winter Storms in Chester County

Date Property Damage Deaths Injuries

Disaster Proclamations Notes

Jan 1966 N/A N/A N/A 1 Winter Storm Feb 1972 N/A N/A N/A 1 Winter Storm Jan 1978 N/A N/A N/A 1 Winter Storm Feb 1978 N/A N/A N/A 1 Winter Storm Mar 1993 N/A N/A N/A 1, 2 Blizzard 1/6/1994 5,000 185 1, 2 Record Snowfall

1/7/1996 19,000 7 N/A 1, 2 Blizzard

2/16/2003 8,000 2 1, 2 Heavy Snow

April 2005 N/A N/A N/A 1, 2 Winter Storm

Source: Pennsylvania Emergency Management Agency, National Climatic Data Center, 2008 Disaster Proclamations: (1) Governor’s Proclamation of Disaster Emergency (2) President’s Declaration of Major Disaster (3) Small Business Administration – Physical Disaster Loans and Economic Injury Disaster Loan


56 July 2009

Table 15. Annual Snow Activity

Earliest Snow Latest Snow Date Amount1 Date Amount1

October 9, 1895 T June 16, 1985 T October 10, 1925 T May 8, 1898 T October 10, 1979 2.1 May 8, 1947 T October 17, 1970 T May 6, 1891 T October 19, 1940 0.3 May 1, 1963 T October 19, 1972 T April 28, 1898 T October 19, 1992 T April 27, 1967 0.1 October 30, 1925 0.7 April 19, 1983 1.3 November 6, 1953 5.4 April 15, 1892 0.3 November 8, 1892 0.8 April 14, 1923 1.8

Latest “First Snow” Earliest “Last Snow” Date Amount1 Date Amount1

January 23, 1890 0.1 February 7, 1951 0.2 January 22, 1966 0.1 February 11, 1913 0.4 January 13, 1955 0.8 February 12, 1925 0.3 January 11, 1938 2.2 February 156, 1930 0.9 December 14, 1923 1.7 February 28, 1945 T December 13, 1941 0.5 March 7, 1929 T December 10, 1920 T March 8, 1922 T December 9, 1900 T March 11, 1946 T December 9, 1948 T March 16, 1901 0.1

1 T = Trace amount Source: Pennsylvania State Climatologist, 2008


57 July 2009

Table 16. Total Snowfall – Chester County

Season Year Oct. Nov. Dec. Jan. Feb. Mar. Apr.

Season Total

69-70 0.0 0.2 13.5 8.5 4.3 3.6 0.0 30.1 70-71 0.0 0.0 2.4 9.4 0.9 4.2 1.1 18.0 71-72 0.0 1.2 0.1 2.9 14.6 0.4 0.2 19.4 72-73 0.7 0.3 0.4 0.4 0.3 0.0 0.0 2.1 73-74 0.0 0.0 7.5 5.2 9.9 0.0 0.0 22.6 74-75 0.0 0.0 0.2 6.6 9.3 2.1 0.0 18.2 75-76 0.0 0.0 0.8 6.9 2.4 6.6 0.0 16.7 76-77 0.0 0.2 3.5 14.8 1.9 0.2 0.0 20.6 77-78 0.0 0.2 0.9 23.6 21.3 7.9 0.0 53.9 78-79 0.0 3.2 0.1 9.7 25.8 0.0 0.0 38.8 79-80 0.5 0.0 2.9 3.4 1.0 6.4 0.4 14.6 80-81 0.0 1.1 3.5 6.2 0.6 7.8 0.0 19.2 81-82 0.0 0.0 7.5 12.8 4.4 2.6 8.4 35.7 82-83 0.0 0.0 3.7 4.7 25.4 2.8 4.4 41.0 83-84 0.0 0.7 3.0 12.4 0.2 14.8 0.0 31.1 84-85 0.0 0.1 1.9 10.0 8.7 0.1 0.7 21.5 85-86 0.0 0.1 3.0 4.3 15.3 0.1 0.9 23.7 86-87 0.0 0.1 1.9 19.8 10.8 0.9 0.0 33.5 87-88 0.0 3.8 2.6 11.0 1.7 0.0 0.0 19.1 88-89 0.0 0.0 0.3 6.8 1.4 4.4 0.0 12.9 89-90 0.0 3.8 6.2 5.3 0.9 1.5 0.8 18.5 90-91 0.0 0.0 7.7 5.2 0.5 2.4 0.0 15.8 91-92 0.0 0.0 0.2 1.8 2.3 5.7 0.0 10.0 92-93 0.0 0.0 1.7 1.3 15.4 17.0 0.1 35.5 93-94 0.0 0.0 0.9 20.5 19.4 9.6 0.0 50.4 94-95 0.0 0.1 0.0 0.3 8.4 1.0 0.0 9.8 95-96 0.0 3.5 13.0 31.5 11.0 4.1 1.0 64.1 96-97 0.0 0.1 0.9 1.8 4.5 4.4 2.7 14.4 97-98 0.0 0.0 1.4 1.8 0.1 0.6 0.0 3.9 98-99 0.0 0.0 0.6 3.5 0.9 5.4 0.0 10.4 99-00 0.0 0.0 0.0 16.4 4.8 0.0 1.4 22.6 00-01 0.0 0.0 5.3 5.9 10.5 2.4 0.4 24.5 00-02 0.0 0.0 0.0 6.4 0.4 0.0 0.0 6.8 00-03 0.1 0.8 12.4 7.1 30.6 0.6 2.4 54.0 00-04 0.0 0.0 10.1 11.2 1.2 6 0 28.5 00-05 0.0 0.0 0.2 11.9 9.6 6 0 27.7



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Table 17. Average Temperature – Chester County

Year Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. 1970 22.6 31.6 36.7 50.3 63.5 69.6 74.5 74.1 69.2 57.4 45.8 33.9 1971 25.9 32.9 38.5 49.4 58.4 71.2 73.6 71.7 68.7 60.1 43.5 39.5 1972 33.5 29.4 38.9 48.4 61.3 66.4 74.8 72.6 66.9 50.2 41.4 37.6 1973 33.5 31.2 45.8 51.5 58.1 72.6 75.5 75.3 67.4 56.5 45.9 36.3 1974 34.3 31.3 41.7 53.3 60.3 67.4 74.2 73.6 64.8 51.6 45.8 37.4 1975 35.2 33.9 39.3 46.7 64.6 70.1 74.4 74.1 62.8 58.3 49.8 34.8 1976 26.9 39.2 44.9 54.8 60.1 73 72.7 72.1 64.7 50.6 38.9 28.8 1977 19.6 32.5 46.6 54.2 64.2 68.2 75.6 73.6 67.5 52.9 46.4 32.2 1978 26.4 23.6 37.6 50.3 59.6 70 72.5 75.3 65.4 53 45.4 36.2 1979 29.3 21.8 44.1 49.9 62.3 67.4 73.2 72.7 65.3 52.8 48.3 36.5 1980 30.6 28.5 38.3 52.7 63.3 67.7 76.2 76.7 69.3 52.7 41.2 30.9 1981 24.3 36.6 38.7 53.5 61.3 70.6 74.8 71.3 64.4 50.9 43.6 32.1 1982 22.5 32.4 39.3 48.5 63.2 66.9 74.3 69.5 64.7 54.3 46.5 39.9 1983 31.6 32.3 42 49 59.1 70 75.6 75.2 66.8 54.8 44.7 30.7 1984 25.1 37.5 34.2 48.9 59 71.2 72.5 73.4 62.2 59.4 42.5 39.7 1985 26 32.8 42.5 53.9 62.9 67.1 73.5 72.2 66.7 56.2 48.2 30.5 1986 30.8 29.8 42.4 51.1 64.3 70.7 75.2 70.7 64.9 55.1 41.2 35.6 1987 29 30.2 43.2 51.1 62.2 71.8 76.6 71.6 65 49.1 44.2 36.1 1988 24.2 31.4 41.3 48.7 61.1 69.1 77.3 75.2 62.7 48.8 44.2 32.6 1989 33.8 31.6 39.4 48.8 59.6 71.3 73.7 72 66.1 55.5 42.6 22.3 1990 37.8 38.4 44.1 51.8 59.3 70.3 74.8 72.3 64 58 46.2 38.1 1991 31.1 36.7 42.9 52.7 67.2 71.6 75.5 74.6 64.3 54.7 43.3 35.9 1992 32 34.1 37.8 49.4 58.2 67.1 72.5 69.3 64.1 50.1 43.2 34.2 1993 34 27.6 35.8 50.2 62.7 70 76.2 74 64.8 52 43.3 33 1994 21.8 27.2 37.4 54.8 58.5 73.3 76.9 70.7 64.3 52.8 48.3 38.4 1995 34.5 28.2 43.4 49.7 59.8 70 76.1 75.2 65.5 57.9 39.7 29.2 1996 27.2 31.4 36.5 51.1 59 71.3 72.3 72.4 66.2 54.2 39.1 37.4 1997 29.2 37.3 41.6 49.1 57.5 68.9 74.2 71.4 64.6 54.8 41.7 35.2 1998 38.3 39.5 43.2 53.4 65.2 69.6 74.6 74.2 68.6 55.1 44.7 39.4 1999 31.6 34.8 39.3 51.3 61.5 71 78.8 73.8 66.9 52.7 48.4 36.7 2000 29 33.8 46 50.6 62.6 70.4 71.2 71.3 64.2 55 42.8 27.8 2001 29 34.5 37.9 51.5 62.2 71.7 72.1 76.2 64.9 55.3 48.5 40.4 2002 36.1 37.9 42.7 54.5 60.2 71.5 77.1 77.2 68.9 54.1 43.1 31.8 2003 25.8 27.4 41.1 49.9 58.1 67.8 75 75.3 66.3 52.6 48.2 34.8 2004 24.2 31.9 43 52.3 67.6 69.3 73.7 73 67.8 53.3 46.4 34.4 2005 29.6 33.5 36.7 53.1 57.4 73.2 76.8 76.6 70.6 56.4 46.6 31 2006 38.3 33.3 42 54 61.5 70.7 77.3 75 64.2 53.3 48.3 40.8 2007 35.1 25 40.3 48.3 63.6 72 73.68 74.03 68.55 61.47 42.84 34.83



59 July 2009

Table 18. Major Wind Storms in Chester County since 1979

Date Description of Storm Deaths Injuries Property Damage

September 1979 Tornado affecting southern Chester County (one death reported in New Garden Township)

1 4 $2,500,000

July 1982 Windstorm affecting the area of north Coatesville

N/A N/A N/A

August 1983 Windstorm affecting West Chester, West Goshen, Westtown, West Bradford and East Bradford Townships

N/A N/A N/A

July 1984 Windstorm affecting Northern Chester County

N/A N/A N/A

September 1985 Hurricane Gloria (heavy rainfall) affecting Eastern Chester County

N/A N/A N/A

July 1988 Tornado in East Nottingham, causing property damage and injury.

0 1 $250,000

November 1989 Windstorm affecting the majority of Chester County

N/A N/A N/A

July 1990 Tornado in Pikeland, causing property damage.

0 0 $250,000

August 1990 Windstorm affecting the majority of Chester County

N/A N/A N/A

September 1991 Tornado affecting the area south of Oxford N/A N/A N/A

July 1992 Tornado affecting the area west of Unionville

0 0 $250,000

August 1992 Tornado affecting the area in the vicinity of Atglen

0 3 $250,000

December 1992 Windstorm affecting the majority of Chester County

N/A N/A N/A

March 1993 Windstorm affecting the majority of Chester County

N/A N/A N/A

May 1993 Tornado affecting the area northeast of Coatesville.

N/A N/A N/A

July 1994 Tornado affecting eastern Chester County. 0 11 $5,500,000

May 1998 Windstorm affecting Atglen, and tornadoes in Daleville and Lenape.

0 2 $1,000,000

September 1999 Hurricane Floyd (heavy rainfall, high winds, and flooding) affecting all of Chester County.

1 1 $5,800,000

November 1999 Tornado affecting Honey Brook. 0 12 $3,000,000

December 2000 Windstorm affecting all of Chester County. 1 1 $360,000

September 2003 Hurricanes Isabel and Henri (heavy rainfall, high winds, and flooding) affecting all of Chester County.

0 0 $35,700,000


60 July 2009

Date Description of Storm Deaths Injuries Property Damage

November 2003 Windstorm affecting all of Chester County. 1 3 $2,200,000 September 2005 Hurricane Katrina (heavy rainfall, high

winds, and flooding) affecting all of Chester County

N/A N/A N/A

January 2006 Windstorm affecting all of Chester County. 0 0 $600,000 June 2006 Heavy rain and severe flooding affecting all

of Chester County, particularly along the Brandywine Basin and Schuylkill River.

0 0 $6,000,000

Source: Chester County Planning Commission, Pennsylvania Emergency Management Agency, National Climatic Data Center, 2008


61 July 2009

Table 19. Pennsylvania Tornado Frequency by Month

Month Frequency Deaths Mean-time (minutes)

January 6 0 23:32 February 1 0 18:35 March 19 1 13:54 April 31 0 18:05 May 108 66 17:30 June 84 3 17:19 July 127 6 15:38 August 55 3 16:26 September 47 1 17:56 October 2 0 14:03 November 21 1 15:10 December 0 0 0

Source: National Climatic Data Center, 2008


62 July 2009

Figure 21.


63 July 2009

Figure 22. Wind Roses for Regional Pennsylvania Airports


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Table 20. Highest Sustained Wind Speed (One-minute average)

Month Day Year Speed Direction Month Day Year Speed Direction January 25 1958 61 NE February 25 1956 59 NW

12 1915 60 NE 15 1939 50 SW 6 1959 52 NW 26 1886 48 NW 3 1913 52 S 23 1880 48 NW 17 1885 52 W 3 1880 48 NE 31 1878 52 E 2 1876 48 NW

March 12 1888 60 NW April 6 1958 59 SW 27 1955 56 NW 5 1952 55 W 9 1942 53 SW 16 1929 50 NE 13 1993 52 ENE 3 1879 50 W 21 1976 50 NW 26 1889 48 NE 3 1896 50 NW 8 1889 48 N

May 24 1933 68 NW June 11 1958 73 NW 10 1889 60 NW 23 1969 57 NW 26 1957 56 SW 30 1906 54 NW 28 2005 52 W 26 1930 51 NW 6 1956 47 NE 1 1889 46 SE

July 14 1931 53 N August 13 1955 67 E 27 1896 53 N 24 1893 55 NE 28 1941 52 N 10 1913 51 W 22 1980 49 SW 6 1977 49 NW 31 1959 47 W 1 1878 48 S 14 1954 47 NNW 14 1919 47 NE

September 15 1904 58 NW October 23 1878 75 SE 11 1889 54 NE 15 1954 73 E 17 1876 52 SE 14 1955 64 SE 12 1960 49 NE 2 1952 62 SW 19 1928 48 NE 4 1877 60 SE

November 28 1958 60 SW December 10 1878 63 SE 24 1877 60 E 5 1902 52 N 25 1950 57 SE 26 1895 50 SW 8 1957 56 SW 22 1916 48 NW 7 1951 56 SE 21 1905 48 SW 4 1989 48 SE 17 1890 48 NE 18 1888 48 NW



65 July 2009

Table 21. Highest Sustained Wind Speeds and Peak Instantaneous Gusts

Speed Direction Date Sustained Wind Speed

75 SE October 23, 1878 73 NW June 11, 1958 73 S October 15, 1954 68 NW May 24, 1933 67 E August 13, 1955 64 NE October 14, 1955 63 SE December 10, 1878 62 WNW October 2, 1952 61 NE January 25, 1958 60 SW November 28, 1958 60 NE January 12, 1915 60 NW May 10, 1889 60 NW March 12, 1888 60 E November 24, 1877 60 SE October 4, 1877

Peak Instantaneous Gusts 94 S October 15, 1954 (Hurricane Hazel) 88 N July 14, 1931 69 W May 28, 2005 66 E March 13, 1993 (Superstorm) 63 SW October 14, 1995



66 July 2009

Table 22. Drought Emergencies in Chester County since 1960 Date Description

1961-1966 Longest hydrologic drought of record. 1976-1977 Meteorological drought (normal 30 inch frost line

increased to five feet.) 1980-1981 Hydrological-drought (county declared emergency). 1983 Agricultural drought (Presidential/ Governor's declared

emergency). 1985 Governor declared emergency. 1988 Meteorologic drought. 1999 Governor declared emergency, Individual Assistance and

Hazard Mitigation Grant Program was amended to include all 67 counties for an agricultural disaster.

2002 Governor declared emergency. Source: National Climatic Data Center, 2008


67 July 2009

Figure 23.


68 July 2009

Figure 24.


69 July 2009

Figure 25.


70 July 2009

Table 23. Sample Chester County Observation Well Report


71 July 2009


72 July 2009

IV. HUMAN-CAUSED HAZARDS

A. Dam Failures Any dam has the potential for creating a major disaster. Dam failures usually occur with little or no notice, wreaking havoc on an unsuspecting community. There are a number of potentially hazardous dams in the Commonwealth, a good portion of which are classified as unsafe. Rapid thaw in the spring, poor maintenance, severe thunderstorms or rain are factors that may facilitate an actual dam break. History/Vulnerability There have been no dam failures in the history of Chester County. Vulnerability of any community is increased by the mere existence of a dam. Proper maintenance and extensive planning for a potential break greatly reduce the risk factors involving dam disasters. As of December 2006, there were 20 dams and seven retention basins in Chester County that met the State requirements for mandatory planning under the Dam Safety and Encroachments Act (Table 24 and Figure 27). Twelve dams are classified as B or C-1, meaning that they present a potential for large loss of life, excessive economic loss, or significant public inconvenience if they fail. In addition to these 12 dams, 2 dams in neighboring Berks County present a potential for destruction in Chester County if they fail. Probability Because of the tremendous dangers resulting from any dam break, measures are being taken to keep probability to a minimum. Chester County is always in the process of evaluating dam data and preparing or updating evacuation plans for the areas potentially affected by a hazard. Currently, three dams in the county do not have finalized plans, but do have plans in progress. According to the Pennsylvania Department of Environmental Protection (PADEP), Division of Dam Safety, all dams in Chester County are in good or excellent condition with current PADEP inspections.

B. Hazardous Materials

Hazardous materials have been an object of concern to emergency management personnel over the past two decades. Increasing awareness of hazards, especially relating to production, use, storage and transportation of such materials, has gained attention at all municipal levels. A hazardous material is defined as a substance or material in a quantity or form which


73 July 2009

may pose an unreasonable risk to health, safety or property due to its physical and/or chemical properties. An increasing number of hazardous materials incidents in Chester County are the result of highway and rail accidents, storage tank leakage, pipeline break or other events. On occasion, these events reach major (disaster) proportions and force people to evacuate and/or lose their homes and businesses. History In Chester County, the areas of concern involving hazardous materials are: 1. Industrial sites that manufacture hazardous substances and/or generate hazardous

wastes, 2. Chemical distributors and/or waste users, 3. Highways and major industrial traffic, 4. Railroads through the community, 5. Pipelines through the area, 6. Airports, 7. Fuel and other hazardous chemical storage facilities, 8. Oil well and terminals, 9. Waste disposal systems, and 10. Nuclear facility material/waste.

The potential for a hazardous materials incident is tremendous considering the growing number of hazardous materials sites in Chester County. According to the Chester County Annual Report on Hazardous Material Emergency Response Preparedness (June 2006), Chester County experienced 68 incidents involving hazardous materials in 2004 and 39 incidents in 2005. Most or these incidents occur during transportation of hazardous materials, or from hydrocarbon (fuel) spills resulting from highway accidents. Out of 107 cases, from 2004 and 2005, 39 involved hazardous materials highway accidents. There were no cases of hazardous materials incidents involving railway transportation in Chester County in 2004 or 2005. There were 11 incidents involving industrial sites/ facilities in 2004 and 2005, including six Superfund Amendment and Reauthorization Act (SARA) planning facilities and one SARA reporting facility. Two of the incidents involved fire. Six of the incidents involved employee exposure or injury. None of the incidents resulted in a fatality. Two additional fires involving suspected hazardous materials were reported in 2004 and 2005. For the same time period, there were 24 cases of reported suspicious powders or other materials, 17 cases of natural gas, propane, oil or gasoline releases (from tanks and pipelines), one case of a residential mercury release and one case of a residential battery acid release. None of these incidents resulted in injury or fatality. For the purpose of this analysis, Table 25 provides and overview of the incidents from


74 July 2009

2005, and Table 26 shows examples of hazardous material incidents in 2004 and 2005. Vulnerability/Maximum Threat Chester County is becoming increasingly vulnerable to the threat of hazardous materials incidents. New industrial complexes and housing developments increase the potential for natural gas or petroleum pipeline incidents. Increasing industrialization brings with it greater sources of hazardous material transportation, storage, use and waste. The activity of the Limerick Generating Station and the Peach Bottom Atomic Power Station also pose a threat involving nuclear material and waste (see Section IV). Chester County currently has 11 hazardous materials waste sites listed on the National Priorities List for Superfund Cleanup (Table 27). Hazardous Substances Any facility using, storing or manufacturing an Extremely Hazardous Substance (EHS) must meet the reporting criteria under SARA Title III, and are required to work with local officials to develop an Emergency Response Plan in preparation of a potential emergency. According to the Chester County Annual Report on Hazardous Material Emergency Response Preparedness, Reporting Year 2005 (June 2006), there were 71 SARA Title III planning facilities in Chester County as of December 31, 2005. Twenty of these facilities are exempt from fees. Facilities that use, store or manufacture other (non-EHS) hazardous substances are required to report their chemical inventories above 10,000 pounds under the Community Right To Know provisions of SARA Title III. As of December 31, 2005, there were 102 additional reporting facilities in Chester County. Only one of these facilities is exempt from fees. There are also 41 reporting facilities in adjacent counties (Berks, Delaware, Lancaster, and Montgomery County) that potentially pose a threat to Chester County. There are 368 different EHSs used at SARA planning facilities in Chester County (22 at exempt facilities). In addition, there are 323 different chemicals used at SARA reporting facilities (2 at exempt facilities). These chemicals pose various levels of concern due to their characteristics, quantity, and use within the facility. According to the Chester County Act 165 Hazardous Material Preparedness Assessment 2006 Update, of the EHSs reported in Chester County, chlorine, a poison and oxidizer, is the most widely used. The majority of the 33 users are water purification or waste treatment facilities. The largest quantity at one site is 22,000 pounds. Sulfuric acid, a corrosive substance, is the second most widely used EHS in Chester County. Most of the 57 facilities that use this substance have large on-site batteries for backup power. These sites do not pose a serious threat. However, there are several other industrial facilities that use sulfuric acid which could be a cause for concern.


75 July 2009

Ammonia, a non-flammable gas and poison, is used at 8 facilities and is the third most widely used EHS in Chester County. Pipelines Chester County has over 400 miles of liquid and gas pipelines. Ten companies operate 27 lines throughout Chester County. Eight of these lines have been identified as transporting liquid products, while the other 20 lines transport gaseous products. The pipelines traverse through 57 of the 73 municipalities in the county. Table 28 and Figure 28 depict the natural gas and liquid (petroleum) pipelines in operation in Chester County as of 2006. Table 29 lists gas and liquid terminals/stations in operation in Chester County as of 2006.

Probability Increasing vulnerability to hazardous materials, whether raw, or waste, cannot be avoided. However, measures can be taken to keep risk at a minimum. Regulation and monitoring of hazardous material/waste facilities should reduce the probability of hazardous materials incidents. In addition, planning and preparation of response measures for hazardous materials incidents should minimize the effect of incidents that do occur.

C. Fire Hazards

Fire, whether human-caused or natural, is an ongoing hazard affecting many communities daily. Although most incidents are well below disaster proportions, the accumulated impact (including injuries, death, and property loss) is often much greater than the impact of the few major disasters that occur. Most fire disasters are averted by early warning and appropriate response. Prevention of those fire hazards can be greatly improved by public education based on historical records, past experiences and examination of circumstances surrounding various situations. History Property loss from fire damage remained fairly constant from 1997 to 2007. Estimated figures range from $9,680,000 to $31,800,000 annually. For example, in 1997 fire loss was $15,472,000 and $26,100,000 in 2007. As of 2007, of the types of fires in Chester County, structure fires are the most prevalent, and the most costly, averaging between $9,300,000 and $14,600,000 in damages annually.


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Vulnerability/Maximum Threat Fire has been and will continue to be a problem of great concern to Chester County. Urban and suburban expansion continues to create multiple family dwellings and industrial complexes vulnerable to potential fire hazards; also, the threat of arson cannot be overlooked. Approximately 40 percent of all fires investigated are considered to be of a suspicious nature; however, of that 40 percent 95 percent are actually proven to be of criminal intent. In order to decrease vulnerability, Chester County is continuing to emphasize public awareness through education, and offers programs to schools and industry alike. Since carelessness is considered the number one cause of fire incidents, it is education that will hopefully decrease fire hazards in the future. Probability The number of fire incidents has remained relatively constant, averaging between 308 and 458 incidents, while keeping a death toll of less than 13 a year. Public education programs and increased emphasis on the use of smoke detectors is hoped to decrease fire death and injury rates. Although forest fire incidents and losses have remained relatively unchanged, it is felt that public education, coupled with decreasing acreage through industrial and residential expansion will decrease forest fire hazards.

D. Transportation Accidents

For the purpose of this report, a transportation accident is defined as an incident involving air, rail and highway travel resulting in death, serious injury, or extensive property loss or damage. Incidents involving hazardous materials are considered in the hazardous materials section of this analysis. History Chester County has three public airports, one public heliport, eight private airfields, and 19 private heliports (Figure 29). The county is located beneath the holding patterns of both Wilmington and Philadelphia International Airports. Arrival and departure patterns for the Philadelphia International Airport are depicted in Figure 30. The county is also in close proximity to flight paths used by the military flying in and out of the Willow Grove Naval Air Station in Montgomery County. Consequently, air travel is a concern to emergency management personnel. In 2005 there were twelve small-aircraft crashes resulting in six injuries and 12 fatalities. To date, there have been no aircraft disasters involving major commercial airlines in the county.


77 July 2009

Chester County is also served by a sizeable rail line system, which includes SEPTA, Amtrak, Conrail, Octoraro Railroad, Canadian Pacific Rail, and the Brandywine Valley Railroad. Within the last decade, there have been no major rail line incidents involving derailment or injury in Chester County. Figure 31 depicts freight rail service in Chester County, as of 2002. Figures 32 and 33 depict passenger rail service and general public transportation in Chester County. The Chester County highway system includes approximately 3,500 miles of roadway. This includes approximately 26 miles of turnpike, 1,050 miles of state and federal highways and 2,386 miles of secondary and municipal roads (Figures 34). According to the Pennsylvania Emergency Management Agency, there were approximately 5,375 motor vehicle accidents in county in 2000, resulting in 61 injuries and two fatalities. Vulnerability/Maximum Threat As stated previously, Chester County has been spared any major aircraft incidents despite its location beneath holding patterns. On the other hand, small aircraft incidents have occurred in the past, and county residents are indeed vulnerable to air traffic hazards. Rail lines pose a hazard to Chester County residents due to heavy commuter traffic and transportation of hazardous materials, which is discussed in the hazardous materials section of this analysis. Chester County experiences heavy traffic daily as a result of commuters, large numbers of resident motorists, and travelers utilizing Interstate 76. Increasing urbanization, tourist trade and the like contribute to the county’s increasing vulnerability to the hazards of motor vehicle traffic. Probability Chester County is experiencing an increase in vehicular traffic. Considering the growing transportation network, daily commuters, tourists and increasing population densities, the county appears vulnerable to accidents involving all modes of available transportation.

E. Energy Emergencies Energy emergencies include both fast-developing fuel shortages (such as those caused by an oil embargo, a power outage, or a natural gas outage) and creeping shortages caused by rising costs of fuel and electricity. Fuel shortages can also be caused by local imbalances of supply. For example, the nationwide balance may sometimes appear satisfactory on paper, but temporary misdistribution can cause fast-developing local hardships. Strikes and severe cold weather, for example, can disrupt home fuel movement and cause regional shortages. In addition, a shortage of energy in one form (e.g. natural gas) can create shortages in


78 July 2009

other fuel substitutes (e.g. propane or heating oil). These emergencies may very well threaten both our health and livelihoods. History During the fuel crisis of 1972-73, Chester County experienced the same effects as the rest of the nation, including long lines at the gas pumps and problems of providing fuel supplies for emergency personnel and vehicles. These effects were again experienced in 1979 with the advent of the "odd-even" system. Since that time, provisions have been made to ensure that emergency vehicles receive ample fuel. The Gulf War in 1990-1991 and currently the War on Terror in Afghanistan and Iraq, also caused problems with fuel supply in the United States. Even though the nation has not experienced a fuel crisis associated with these conflicts, the actual and anticipated oil shortages have spurned substantial increases in fuel prices. Vulnerability/Maximum Threat As a result of fuel price increases, low-income households have become more vulnerable to utility shutoffs. Therefore, the local electric companies offer assistance through a variety of programs tailored to low-income customers. Accidents, strikes or other situations may cause temporarily localized problems, but it is felt that there would be no extended period where residents would be without fuel or electricity. Probability Depending on international affairs and tensions, a major fuel crisis could develop in the future. However, significant changes seem to have reduced the likelihood of another major oil embargo. In response to drastic fuel price increases, alternative sources of energy, conservation, and improvements in fuel efficiency have lessened the demand for oil. Subsequently, the probability that another 1973-type crisis will occur has been reduced, but not eliminated.

F. Civil Disorders

A civil disorder is defined as any incident which disrupts community affairs, threatens the health and safety of the population or causes the destruction of property. Civil disorders include the following: terrorist attack, bomb threats, riots, strikes or demonstrations which may encompass large portions of the community. History Because of the rural nature of a good portion of Chester County, residents have not experienced any major civil disorders. There have been a number of sporadic incidents,


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none of which have affected large numbers of the total population. Most of the incidents have been relatively localized and short-lived. A list of civil disorders that have occurred since 1973 is given below. 1. Labor disputes have caused unrest, violence, injunction and/or strike situations.

Major incidents occurred at Diversified Printing, National Rolling Mills, Kennett Square NVF, Bishop Tube, Mathey-Bishop, and Lukens Steel. In addition, there was some unrest experienced in 1991, during attempts to unionize the migrant workers in the Kaolin Mushroom Co. in southern Chester County.

2. No racially motivated incidents have occurred in the county since 1973. 3. The nationwide trucker’s strike in 1979 brought violence to the Route 30 Bypass

near Coatesville. 4. A Chester County Prison cell fire in 1982 caused moderate disruption. A large

number of people were affected by smoke inhalation and a number of guards were sent to the hospital.

5. Commuters were affected by SEPTA Rail strike that occurred from March through June of 1983.

6. There was an incident of terrorism in West Goshen in 1983, which involved a dangerous hostage situation. Hostage situations happen approximately once or twice every couple of years.

7. Bomb threats are an ongoing concern of Chester County residents. An actual bomb was discovered in the West Goshen Shopping Center in June 1984. More recently, a series of bomb threats occurred during the early 2000’s. Over twenty individual explosive devices were discovered in northern Chester County over an eighteen month period. These threats resulted in evacuations, traffic rerouting, and destruction of personal property.

8. Following the September 11, 2001 terrorist attacks, there were multiple reports of anthrax contamination throughout Chester County, which resulted in evacuations. Anthrax contamination could not be confirmed in any of the incidents.

9. A series of arson fires occurred in and around the City of Coatesville throughout 2008 and 2009. During this period, over fifty arson fires were set to residences and businesses, resulting in significant property damage.

10. In the past couple decade there have been several incidences involving the abortion controversy, especially within the last five years.

Other civil disorders have occurred throughout Chester County. However, the impact of these other incidents on local residents was minimized due to the moderate size of the incident and quick response of the agencies/parties involved. Probability Civil disorders in Chester County should not increase significantly. However, with the rapid urban expansion that is occurring, attention must be paid to the probability that civil disorders may increase. Strike situations, over-crowding, and racial confrontations cannot be ignored in rapid-growth situations.


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G. Fixed Nuclear Facilities

Portions of Chester County fall within a ten mile radius (EPZ) of two nuclear facilities. Based on information from the 2000 U.S. Census, the Pennsylvania Emergency Management Agency estimates that the Peach Bottom Atomic Power Station EPZ includes approximately 2,634 county residents (Figure 35), and Limerick Generation Station includes about 69,780 residents (Figure 36). The county is also located, all or in part, in the 50-mile radius "ingestion exposure pathway” of four additional facilities (Figure 37 and Table 30). Limerick and Salem include the entire county; Peach Bottom includes all but the far northeastern tip; Three Mile Island includes the entire western portion of the county.

Should an accident occur at a nuclear power plant, the area within this 50-mile radius may receive some radioactive contaminants in very small amounts. While such amounts are of lesser concern in terms of external exposure, protection of the food chain, particularly milk, is important in preventing internal exposure due to ingestion of radioactive contaminants. If an accident should occur, state agencies would sample milk, livestock feed and forage, crops, farm water and public water supplies within the ingestion exposure pathway. In such incidents, county emergency management agencies may be asked to assist in gathering samples and participate in implementing controls of food and water supplies. The probability of a radiation release from a nuclear power plant (in sufficient quantity to constitute a threat to the health and safety of the people of Chester County) is remote, given all of the precautions and safety regulations now in effect. However, the possibility exists for such an event and must be considered.

H. Nuclear Attack

Among all hazards, the threat of nuclear war is by far the most awesome in scope and potential for destruction. Certain areas identified as high risk or target areas are likely to experience direct effects of weapons such as blast, heat and initial radiation resulting in immediate and almost complete destruction of a four-mile radius. The impact of direct and secondary events including flooding, fire, disruption of power, fuel and water supplies, and the release of other hazardous materials may seriously impact a 10 to 20-mile radius. When a nuclear bomb explodes, the immediate effects are an intense light (brighter than the sun), heat (thousands of degrees), blast and radiation. Explosions on or near the ground create large quantities of dangerous radioactive particles from irradiated dirt sucked into a fireball as it sweeps upward to form a mushroom cloud. These radioactive particles are called fallout. They begin falling back to earth in 30 minutes and mostly within the first 24 hours after the explosion. The fallout gives off invisible gamma rays, an excess of which can kill or injure people.


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In a nuclear attack, the size of the weapon would determine the area of damage. People close to the explosion would be killed by the blast and heat. A few miles away, people would be exposed to the blast and heat to a lesser extent but would also be threatened by fires caused by the explosion, and fallout. Outside of the immediate danger area, radioactive fallout would be the main danger. The invisible gamma rays cause physical and chemical changes in the body’s cells, which can result in radiation sickness and even death. Non-lethal doses of radiation would cause sickness in varying degrees. Vulnerability/Maximum Threat The Federal and Pennsylvania Emergency Management Agencies, FEMA and PEMA, respectively, have identified four basic criteria for being at “risk” to a nuclear attack:

1. U.S. Military Installations; 2. Military supporting industries (industrial, transportation, etc.); 3. Other industries essential to a wartime economy; and 4. Populations of 55,000 or more.

FEMA has classified Chester County as a host risk county, meaning that portions of the county are projected to be at risk from the direct effects of a nuclear attack. As shown in Figures 38 and 39, the northeastern portion of the county is at risk. Chester County is located in the eastern seaboard area, in close proximity to and/or including major population centers, port cities, and centers of numerous major industries. Probability FEMA suggests that the probability of a nuclear attack is low, or less than one chance in 100 years (i.e. less than 1%). Estimates of the probability of the United States’ involvement in a major nuclear war vary from as low as one percent to 50 percent by experts in international affairs, military strategists and technologists of modern warfare.


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Figures and Tables Section IV


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Table 24. Chester County Dams

ID No. Dam Name Location Classification 15-001 Pickering Creek Schuylkill Twp. B-1 15-004 Rock Run West Caln Twp. B-1 15-146 Milltown West Goshen Twp. C-I 15-266 Township Line West Goshen Twp. B-1 15-273 Welkinweir East Nantmeal Twp. C-2 15-2S1 Pine Grove Lower Oxford Twp. B-1 15-295 Shangri-La New Garden Twp. C-1 15-296 Marsh Creek Upper Uwchlan Twp. B-1 15-298 R.G. Struble Honey Brook Twp. B-1 15-301 Beaver Creek East Brandywine Twp. B-1 15-304 Barneston Wallace Twp. B-1 15-307 Green Valley Farms New Garden Twp. C-2 15-315 Linpro Tredyffrein Twp. C-2 15-316 Timbers East Brandywine Twp. C-2 15-323 Oxford Wastewater Lagoons Lower Oxford Twp. B-2 15-327 Waynesbrook Easttown Twp. C-2 15-333 Thomas Meeting West Whiteland Twp. C-2 15-335 Radley Run East Bradford Twp. C-2 15-360 Hibernia West Caln Twp. B-1 15-339 Whitford Bridge Detention Basin West Whiteland Twp. C-2 15-330 Thompson Dam 4 (Stream 1) Schuylkill Twp. C-3 15-329 Thompson Dam 1 (Stream 1) Schuylkill Twp. C-3 15-371 Herr Foods Storage Lagoon West Nottingham Twp. C-2 15-372 Wharton Blvd. Stormwater Dam Uwchlan Twp. C-2 15-387 John Stoltzfus Dam Honey Brook Twp. C-3 15-381 Walker Farm Lagoon East Marlborough Twp. C-2 15-364 Crossing No. 5 Dam New Garden Twp. C-2 Other Dams That Affect Chester County Blue Marsh Berks County Hopewell Berks County

Source: PADEP Division of Dam Safety, 2006


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Figure 27.


85 July 2009

Table 25. Hazardous Materials Incidents Overview

Statistic Number Total Incidents: 39 Incidents at SARA Planning Sites: 6 Incidents at SARA Reporting Sites: 1 Incidents at Non-SARA Sites (including residential):

13

Incidents at Transportation Sites: 19 Fire Department Responses: 37 Haz Mat Team Responses: 15 DES Staff Responses: 18 Evacuations: 1 Incidents with Injuries: 5

Source: Chester County Department of Emergency Services, 2005


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Table 26. Chester County Hazardous Materials Incidents Detail

Date / Time Location Facility Chemical Released /

Amount 01/12/2004 09:52 East Whiteland Twp. High School Natural Gas / 1 lb. 01/20/2004 10:50 West Pikeland Twp. Residential Fuel Oil / 200 gal. 01/21/2004 12:30 Tredyffrin Twp. Transportation Diesel Fuel / 125 gal. 01/30/2004 09:11 Warwick Twp. Transportation Fuel Oil / 20 gal. 02/04/2004 07:34 Penn Twp. Transportation Diesel Fuel / 100 gal. 02/23/2004 14:12 Willistown Twp. Transportation Fuel Oil / 600 gal. 02/29/200411:20 Coatesville City Industrial Mercury / 1 oz. 03/08/2004 21:42 Upper Uwchlan Transportation Unknown (Clay) / 10 oz. 03/16/2004 10:15 West Bradford Twp. Transportation Gasoline / 1 gal. 03/16/2004 10:46 Wallace Twp. Industrial Gasoline Vapor / 1 ft.3 03/22/2004 11:45 West Goshen Twp. Transportation Suspicious Powder / 1 oz. 04/01/2004 08:37 Upper Uwchlan Transportation Diesel Fuel / 30 gal. 04/01/2004 22:13 West Goshen Twp. SARA Planning Ammonia / NR 04/09/2004 10:05 West Fallowfield Twp. Transportation Diesel Fuel / 10 gal. 04/15/2004 18:37 Lower Oxford Twp. Transportation Diesel Fuel / 100 gal. 04/17/2004 09:46 Franklin Twp. Water Black Substance / 5 gal. 04/24/200419:08 London Grove Twp. Industrial Propane / 100 lbs. 05/12/2004 22:26 East Vincent Twp. Transportation Diesel Fuel / 50 gal 05/26/2004 10:31 Tredyffrin Twp. Transportation Food / NR 05/26/200411:46 Tredyffrin Twp. Transportation Diesel Fuel / 75 gal. 05/28/2004 12:55 East Goshen Twp. Industrial Sodium Hydroxide / 1 oz. 05/30/2004 13:10 West Caln Twp. Industrial Propane / 100 gal 05/30/2004 19:25 Easttown Twp. Transportation Diesel Fuel / 75 gal 06/01/2004 15:16 London Grove Twp. Transportation Diesel Fuel / 40 gal 06/06/2004 12:24 East Pikeland Twp. Residence Unknown Substance / 1 oz. 06/09/2004 10:00 East Marlborough Transportation Diesel Fuel / 50 gal 06/09/200412:03 Franklin Twp. Industrial Propane / 600 gal. 06/09/2004 17:56 West Chester Police Incident Suspected Chemical / 1 oz. 06/23/200413:20 Uwchlan Twp. Transportation Sodium Hydroxide / 5 gal 06/23/2004 20:18 East Whiteland Twp. Industrial Sodium Hydroxide / 1 L. 06/27/2004 15:00 Phoenixville Borough Residential Suspicious Powder / 1 oz. 06/28/2004 21:35 Charlestown Twp. Transportation Motor Oil / 100 gal. 07/05/2004 18:00 West Fallowfield Twp. Police Incident Unknown Corrosive / 30 oz. 07/09/2004 12:42 East Goshen Twp. Transportation Diesel Fuel / 40 gal 07/11/2004 15:36 West Fallowfield Twp. Police Incident Corrosive Material / 2 L. 07/14/2004 19:46 East Whiteland Twp. Transportation NA / NR 07/18/200412:28 Phoenixville Borough Transportation Motor Oil / 3 gal. 07/22/2004 15:01 East Bradford Twp. Transportation Propane / 250 gal. 07/24/2004 10:20 Uwchaln Twp. Transportation Diesel Fuel / 80 gal


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Amount 07/25/2004 17:00 New Garden Twp. Transportation Aviation Fuel / 40 gal 07/30/2004 17:54 Wallace Twp. Industrial Freon / NR 07/31/2004 15:05 Easttown Twp. Transportation Antifreeze / 1 gal. 08/02/2004 07:58 West Whiteland Twp. Transportation Unknown Vapor / NR 08/06/2004 11:21 North Coventry Twp. Transportation Sulfuric Acid / NR 08/11/2004 07:51 Oxford Borough Transportation Fuel oil / 20 gal. 08/29/2004 22:52 East Caln Twp. Transportation Propane / 10 gal. 08/31/2004 06:50 South Coventry Twp. Transportation Gasoline / 20 gal 09/11/2004 11:33 Laschuylkill Twp. Transportation Diesel Fuel / 30 gal. 09/12/2004 13:18 West Fallowfield Twp. Police Incident IED / NR 09/13/2004 12:42 Charlestown Twp. Transportation Septic / 1500 gal. 09/29/2004 00:14 West Chester Borough Residential Fuel Oil / 10 gal. 10/02/2004 08:01 West Pikeland Twp. Residential Fuel Oil / 100 gal. 10/10/2004 12:48 West Caln Twp. Residential Rust Fungus / NR 10/10/2004 14:11 West Bradford Twp. Industrial Natural Gas / 100 lbs. 10/11/2004 14:28 East Goshen Twp. Police Incident Suspicious Powder / NR 10/14/2004 10:08 Uwchlan Twp. Transportation Gasoline / 20 gal. 10/15/2004 21:25 West Pikeland Twp. Transportation Gasoline / 10 gal. 10/17/2004 08:30 East Marlborough Twp. Transportation Fuel Oil / 40 gal. 10/21/2004 21:18 Highland Twp. High School Sodium Cyanide / 3 gr. 10/25/2004 09:45 Caln Twp. Industrial Liquid Oxygen / 150 lbs. 10/26/2004 14:14 West Brandywine Twp. Residential Mercury / 8 oz. 11/01/2004 07:56 Kennett Square Boro. Transportation Gasoline / 5 gal. 11/10/2004 09:11 East Caln Twp. Residential Propane / 100 lbs. 11/11/2004 12:20 West Bradford Twp. Residential Fuel Oil / 240 gal. 11/11/2004 17:20 Westtown Twp. Police Incident Suspicious Powder / NR 11/18/2004 12:57 West Chester Boro. Industrial Methacrylic Acid / 20 gal. 12/08/2004 09:47 Honeybrook Twp. Transportation Propane / 1 gal. 12/14/2004 19:03 West Brandywine Twp. Industrial Fuel Oil / NR 01/10/200510:22 Sadsbury Twp. Transportation Fuel & Oil / 100 gal 01/13/2005 05:00 West Caln Twp. Transportation Gasoline / Unknown 01/19/2005 07:36 East Caln Twp. Transportation Diesel Fuel / 50 gal. 02/09/2005 17:01 West Brandywine Twp. Transportation Fuel Oil / NR 02/25/2005 12:28 Uwchlan Twp, Industrial Iodine / 2 gr. 03/11/2005 09:59 East Vincent Twp. Transportation Motor Oil & Gas / 2 gal. 03/15/2005 17:37 Elk Twp. Transportation Methanol / NR 03/23/2005 10:29 West Chester Borough Police Incident Black Powder / NR 04/02/2005 21:20 West Pikeland Twp. Water Oil Sheen / NR 04/07/2005 09:06 Tredyffrin Twp. Industrial Vanadium Pentoxide / NR

Oxalic Acid / NR 04/18/2005 11:15 West Nottingham Twp. Transportation Diesel Fuel / 100 gal.


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Amount 04/19/2005 01:40 West Goshen Twp. Industrial Phosphoric Acid / 1 lb. 04/24/2005 19:56 West Caln Twp. Transportation Motor Oil / 1 gal. 04/25/2005 19:02 Pocopson Twp. Transportation Radiological Equip. / NR 04/27/2005 12:01 Penn Twp. Transportation Gasoline / 20 gal. 05/08/2005 22:48 Sadsbury Twp. Industrial Comm. Floor Cleaner / NR 05/11/2005 08:26 East Pikeland Twp. Industrial Sodium Hydroxide / NR

Sulfuric Acid / NR 05/13/2005 15:58 Honeybrook Twp. Transportation Waste Oil / NR 05/15/2005 16:57 Coatesville City Water Oil Sheen / 1 gal. 05/23/2005 20:39 Warwick Twp. Residential Liquid Oxygen / 10 lbs. 06/10/2005 11:07 West Caln Twp. Police Incident Illegal Drug Lab / NR 07/13/2005 08:19 Tredyffrin Twp. Police Incident Suspicious Powder / 1 oz. 07/13/2005 10:17 West Fallowfield Twp. SARA Planning Undet. Explosive / NR 07/17/2005 18:14 Spring City Borough Transportation Fuel Oil / 20 gal. 07/24/2005 07:00 West Nottingham Transportation Oil & Antifreeze / 2 gal. 07/27/2005 20:38 Willistown Twp. Water Sulfuric Acid / 5 gal.

Liquid Sewage / 100 gal. 07/27/2005 20:59 New Garden Twp. Transportation Oil & Fuel / 20 gal. 08/08/2005 17:51 Kennett Twp. Transportation Diesel Fuel / 100 gal. 08/29/2005 10:34 Tredyffrin Twp. Transportation Water Treat. Chem. / 5 gal. 09/02/2005 08:34 West Goshen Twp. Transportation Fuel Oil / 2 gal. 09/05/2005 17:48 West Goshen Twp. Water Household Waste / NR 09/19/2005 08:26 West Goshen Twp. Industrial Cleaning Chem. / NR 10/09/2005 06:45 West Fallowfield Twp. Transportation Diesel Fuel / 20 gal. 10/10/2005 11:58 New Garden Twp. Water Gasoline / 10 gal. 10/22/2005 17:35 East Pikeland Twp. Industrial Sodium Hydroxide / 10 gal. 10/30/2005 16:35 Downingtown Borough Residential Fuel Oil / 100 gal. 11/09/2005 15:57 East Nanmeal Twp. Transportation Liquid Nitrogen / NR 11/26/2005 17:45 Malvern Borough Industrial NA / NR 12/19/2005 13:09 East Bradford Twp. Transportation Fuel Oil / 1600 gal. Source: Chester County Department of Emergency Services, 2006


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Table 27. Superfund Sites in Chester County

No. EPA ID Site Name Location 1 PAD004351003 A.I.W. Frank/Mid-county Mustang Exton, PA 19341 2 PAD980539985 Blosenski Landfill Site Coatesville, PA 19320 3 PAD014353445 Chemclene Corp. Malvern, PA 19355 4 PAD077087989 Foote Mineral Frazer, PA 19355 5 PAD980691703 Kimberton Auto Service Kimberton, PA 19442 6 PAD981938939 Old Wilmington Rd GW Contamination Sadsburyville, PA 19369 7 PAD980692594 Paoli Rail Yard Paoli, PA 19301 8 PAD002353969 Recticon/Allied Steel Corp. Parker Ford, PA 19457 9 PAD980829527 Walsh Landfill Honeybrook Twp., PA 19344 10 PAD980537773 William Dick Lagoons Wagontown, PA 19376 11 PAS000441337 Strasburg Landfill Newlin, PA 17820

Source: Chester County Department of Emergency Services


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Table 28. Chester County Pipelines

Company Number of Lines

Liquid Pipelines Colonial Pipeline 1 PPL Interstate 1 Buckeye Pipeline 4 Sunoco Pipeline 2 Gas Pipelines Columbia Gas Transmission 8 Eastern Shore 1 Texas Eastern (TEPPCO) 2 Trans-Continental 7 UGI 1 Lukens Steel (private) 1



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Figure 28.


92 July 2009

Table 29. Chester County Terminals/Pumping Stations

Company Location Gas Terminals/ Pumping Stations Columbia W. Bradford Township - Poorhouse Road Eastern Shore Londonderry Township - Rte. 926, Dalevale, PA Texas Eastern Production Upper Uwchlan Township - Little Conestoga Road Liquid Terminals/Pumping Stations Buckeye Pipeline East Whiteland Township - Route 30 Sun Pipeline Upper Uwchlan Township - Route 100 Sun Pipeline East Whiteland Township

- Route 30 Sun Pipeline W. Brandywine Township - Route 322



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Figure 29.


94 July 2009

Figure 30.


95 July 2009

Figure 31.


96 July 2009

Figure 32.


97 July 2009


98 July 2009

Figure 34.


99 July 2009

Figure 35.


100 July 2009

Figure 36.


101 July 2009

Figure 37.


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Table 30. Pennsylvania at Risk Population in the Vicinity of a Nuclear Power Plant

Facility County At Risk Population Beaver Valley Power Station Beaver 89,132 Limerick Generating Station Berks 22,169

Chester 69,780 Montgomery 152,464

Peach Bottom Atomic Power Station Chester 2,634 Lancaster 22,539 York 11,242

Susquehanna Steam Electric Station Colombia 19,162 Luzerne 49,341

Three Mile Island Nuclear Station Cumberland 9,515 Dauphin 99,955 Lancaster 31,859 Lebanon 906 York 59,659

Source: Pennsylvania Emergency Management Agency, 2006 Nuclear Power Plant Fact Sheets


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Figure 38.


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Figure 39.


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V. SUMMARY Chester County, by virtue of its geographic location and topography, is subject to natural hazards such as flooding, winter storms, droughts, tornadoes and earthquakes. Historically, all of these hazards have affected or threatened the county. Major snowstorms and flooding have the greatest potential to cause significant disruptions, mainly because residents are not prepared for these natural hazards. In addition, earthquake occurrences have become more frequent in adjacent counties, prompting study of the fault lines in the greater Philadelphia area. Chester County has experienced human-caused disasters which have affected sizable segments of our population. Hazardous materials incidents, fires, transportation accidents, and energy emergencies have historically occurred in the county. Nuclear attack, however remote the possibility, also cannot be discounted. Of all the human-caused hazards noted, hazardous materials incidents are of immediate importance. The dramatic increase in the use, storage, transport, manufacturing and disposal of hazardous materials increases the frequency and potential for hazardous materials incidents. All levels of government and all emergency service organizations must be aware of hazards that affect the county so that appropriate response, precautions and preventive measures can be implemented to reduce or eliminate the effects of those hazards. The Chester County Department of Emergency Services is committed to cooperating and coordinating with public and/or private agencies to reduce the effects of these hazards.


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VI. REFERENCES Chester County Department of Emergency Services (DES), Resources Center. Chester County DES, Chester County Act 165 Hazardous Materials Preparedness Assessment 2006 Update, May 2007. Chester County Fire Marshal’s Office. Chester County Planning Commission (CCPC), Chester County Profile 2002, December 2003 CCPC, Maps and Charts Inventory. Chester County Tax Assessor’s Office Chester County Water Resources Authority. Chester County Website: http://dsf.chesco.org Delaware Valley Regional Planning Commission Delaware River Basin Commission Pennsylvania Department of Transportation (PennDOT), Bureau of Rail Freight, 2008 Rail Map ftp://ftp.dot.state.pa.us/public/Bureaus/railfreight/parailnewmajhwys.pdf Pennsylvania Department of Conservation and Natural Resources (DCNR), Bureau of Forestry, Forest District #17. Pennsylvania Department of Environmental Protection (PADEP), Division of Dam Safety Pennsylvania Emergency Management Agency (PEMA) PEMA, Vulnerability Analysis of Hazards, Harrisburg, Pennsylvania, 1980 and 1988 PEMA, Commonwealth of Pennsylvania Emergency Operations Plan, Annex “E”, Radiological Emergency Response to Nuclear Power Plant Incidents, August 1990. PEMA, Nuclear Power Plant Fact Sheets: Beaver Valley Power Station, 2006. PEMA, Nuclear Power Plant Fact Sheets: Limerick Generating Station, 2006. PEMA, Nuclear Power Plant Fact Sheets: Peach Bottom Atomic Power Station, 2006. PEMA, Nuclear Power Plant Fact Sheets: Susquehanna Steam Electric Station, 2006.

http://dsf.chesco.org/�

ftp://ftp.dot.state.pa.us/public/Bureaus/railfreight/parailnewmajhwys.pdf�


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PEMA, Nuclear Power Plant Fact Sheets: Three Mile Island Nuclear Generating Station, 2006. Pennsylvania State Climatologist, http://pasc.met.psu.edu/PA_Climatologist/index.php Pennsylvania State Data Center, Chester County Profile, 1990 Susquehanna River Basin Commission United States Census Bureau, County Business Patterns United States Department of Commerce, Bureau of Economic Analysis, Regional Economic Information System United States Department of Commerce, National Weather Service (NWS). NWS, Tornado Guide, 1992. http://www.nssl.noaa.gov/edu/safety/tornadoguide.html United States Department of Commerce, National Oceanic and Atmospheric Administration (NOAA), National Climatic Data Center (NCDC). United States Department of Commerce, NOAA, Northeast Regional Climate Data Center. United States Department of the Interior, Facing Geologic and Hydrologic Hazards, 1981. United States Department of the Interior, United States Geological Survey (USGS), National Earthquake Information Center.

HAZARDS VULNERABILITY ANALYSIS...Natural and mancreated disasters were then - reviewed to determine...

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