Overview of Geologic Hazards• From water movement (coastal flooding from

hurricanes, beach erosion, inland flooding, drought)

• From earth movement (earthquakes, mudflows,

landslides, subsidence, expansive soils)

• From dangerous minerals (arsenic, asbestos, radon)

• From contaminated water (groundwater, surface water, distribution system water)

Magnitude and Frequency

Coastal Flooding

Living in harm’s way – behind the levee

Storm moves 30 mph

Wind speed 120 mph

Wind speed 120 mph

Net 150 mph

Net 90 mph

Hurricanes

Katrina 2005 1836+(Mississippi, Louisiana)

Katrina 2005 $100 billion(Mississippi, Louisiana)

Property DamageCostliest U.S. Atlantic hurricanes

Cost refers to total estimated property damage

Rank Hurricane Season Damages, $billion

2 Ike 2008 $29.5 

1 Katrina 2005 $108 

4 Wilma 2005 $21 

7 Rita 2005 $12 

5 Ivan 2004 $18.8 

6 Charley 2004 $15.1 

8 Frances 2004 $9.51 

10 Jeanne 2004 $7.66 

9 Allison 2001 $9 

3 Andrew 1992 $26.5 

Source: NOAA[2]

Katrina: Fatalities > 1800

Levee design and construction inadequate

Geologic Changes – New Inlet

Hurricane Magnitude

Saffir-Simpson scaleIntensity Wind speed mph Storm surge ft

Category 1 74-95 4-5

Category 2 96 to 110 6-8

Category 3 111 to 130 9-12

Category 4 131-155 13-18

Category 5 > 155 > 18

Hurricane Magnitude - Frequency

Saffir-Simpson scaleIntensity Wind speed mph Storm surge ft Number

1850-2005

Category 1 74-95 4-5 109

Category 2 96 to 110 6-8 71

Category 3 111 to 130 9-12 74

Category 4 131-155 13-18 17

Category 5 > 155 > 18 3

Hurricane Frequency

Hurricane Frequency

Hurricane Cyclicity

Long-term trend

Remediation

1.Building codes

2.Levees

3.Evacuation

Inland Flooding --Cinti 1937

385 dead,

one million homeless,

$500 million in property damage (= $7.6 billion today)

Flood intensity – gage height

Flood Frequency (Cinti)

Remediation

Flood wallBarrier dam

Beach Erosion

Longshore drift

Beach Erosion -- Intensity

Beach Erosion -- Intensity

Beach Erosion -- Frequency

Beach Erosion -- Remediation

Walls

Beach Erosion -- Remediation

Nourishment

Earth Movement

Earthquakes

Earthquake Susceptibility

Earthquakes-- FrequencyMagnitude Acceleration # per

year

8-9 1

7-8 18

6-7 120

5-6 800

4-5 6200

3-4 50,000

Remediation

1.Building codes

Landslides

Landslide frequency

Cincinnati OH: remediation of landslides on public property

1974-1993 Feet/yr Dollars/yr

Pier walls 442 457,780

Mt Adams 1650 44,489,926

Remediation

Pier walls - $1000 per lineal foot

Subsidence

Volcanoes

Volcanoes -- Lahars

Lahars – magnitude (extent)

Lahars – magnitude (thickness)

Lahars – frequency

• Mt Rainier recurrence intervals

• Large lahars (reach ocean) – 1000 years• Intermediate (confined to apron

• of the mountain) – 100 years

• Small (confined to slopes) – 10 years

Dangerous minerals – Pb phosphate

Occurrence of Arsenic in Groundwater in US

SW Ohio

Radon – enters home from soil

Contaminated water

Water Pollution – Inorganics in Groundwater

GW flow

Significant solvent contamination has

traveled through the groundwater

outside the plant boundaries at

Pristine.

flowWater flow

Water Pollution – Organics in Groundwater

Water Pollution – MagnitudeRank Appendix IX Constituent Detectable Events

b

Sites c

No. %

1 Dichloromethane 4558 157 32.82 Trichloroethylene 4001 132 27.63 Tetrachloroethylene 2913 111 23.24 trans 1,2-Dichloroethylene 2357 116 24.25 Chloroform 2137 89 18.66 1,1-Dichloroethane 1706 108 22.57 1,1-Dichloroethylene 1653 75 15.78 1,1,1-Trichloroethylene 1609 101 21.19 Toluene 1430 131 27.3

10 1,2-Dichloroethane 1339 82 17.111 Benzene 1169 120 25.112 Ethylbenzene 733 109 22.813 Phenol 679 79 16.514 Chlorobenzene 662 86 1815 Vinyl chloride 580 79 16.516 Carbon tetrachloride 484 32 6.717 bis (2-ethylhexyl) phthalate 383 89 18.618 Naphthalene 369 61 12.719 1,1,2-Trichloroethane 270 37 7.720 Chloroethane 269 61 12.7

Water Pollution -- Surface Water

GCWW intakes

Proposed sewer outfall

Cryptosporidium

Water Pollution – From the distribution system

Litharge

Cu sulfate

Mn oxide

Plattnerite

Litharge

Cu sulfate

Mn oxide

Plattnerite + Mn oxide

Pb carbonate

Water Pollution – From the distribution system

Water Pollution – From the distribution system

Pb islands

What do we do?

1. Understand the underlying geology

2. Calculate probability of an event

3. Estimate the severity of possible effects

4. Establish risk to populations & environment

What do we do?

5. Reducing the riskA. Avoidance

B. Building codes

C. Evacuation plans

D. Removal of endangered structures

E. Protective engineering