Battle Creek Flood Communication

8/2/2019 Battle Creek Flood Communication

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Date: 3/18/12 To: South Salem Residents of Ward 4 Re: January Flooding Question and Answer

Attached to this letter you will find responses to many of the questions that were raised from the Flood Talk held at the South Salem Senior Center. The intent of these responses is to provide feedback to some of the concerns raised by area residents. Where facts are requested I have attempted to provide them and where appropriate I have shared my personal understanding. Some responses are from staff and others are from me. Also attached to this letter is a Q&A document put together by the City. It addresses some of the same questions and includes others that have come up since the meeting. I intended to send out the communication much earlier than this, however there are a few critical pieces of information I was waiting on. Most notably would be the size of the storm event that we had in terms of return frequency (ie was this a 50 year event, 100 year, etc). This storm was recently determined to be an 80 year event at the airport, with a higher amount of rain being measured in other areas of town. Unfortunately we don’t have a frequency analysis at the Battle Creek rain gauge to



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Battlecreek Community Meeting February 7, 2012 Concerns, Comments, and Questions

Issue Councilor or StaffComments (3/2/12) Stat

Trees

Are there alternatives to cutting large, healthy trees?

Modifications actually hurting negative impact (e.g. tree removal) (Battle Creek

Woods/Fairway houses)

We keep cutting the trees that could hold the water including in the Golf Course

drainage. Can we engineer more sensitively?

Storm drainage

Storm sewer cleaning concern

I‐5 culvert?

Were culverts blocked?

Note: water backing up from existing storm drains

Note: City has set aside specific/dedicated storm water funds

Need for updated drainage dataRich Clausen ‐ I don't recall where this comment was headed. It is my hope that the

information in this communication and other attachments might fulfill this request.C

No storm drains near Doral

Rich Clausen ‐ This could be a result of previous stormwater codes. The

neighborhoods surrounding Battlecreek were all constructed previous to 1984 and

therefore had much less stringent requirements for stormwater drainage or

detention.

As it was, there were storm drains on 13th that were flowing ONTO the street, so it

may almost have been better for residents that there were not drains. I would be

f hb d l k f l h h

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Item

City Staff ‐ The drainage basins contributing to flows in the Battlecreek area are quite

large and the overall influence of trees on the severity of the 2012 flooding is relatively

small. Construction of the Waln Creek improvements, the new collector street, and a

new berm around the east and south part of the site required removal of

approximately 70 trees. Several thousand new plants of native species and

appropriate to a stream‐side environment will be planted adjacent to Waln Creek as

part of the project. Street trees will be planted along the new street and Commercial

Street.

City Staff ‐ Public Works crews routinely clean all stream grates on a programmed

schedule defined in our Stormwater Management Manual as well as when requested.

The grate at Gilmore field was cleaned three times on the January 18, 2012, the day

before the major rainfall hit, as were many other grates in town. The city also has an

annual program in which college interns and students clean 46 miles of streams. Last

year, the team removed over 6 tons of debris that people had discarded into city

streams plus 95 cubic yards of unnatural debris.

Rich Clausen ‐ I did not see the culverts at I‐5 but it is my understanding, from second

and third hand sources, that the culverts did not reach capacity.




Issue Councilor or StaffComments (3/2/12) StatItem

Development impact

No water solutions yet as school development occurs

Plans for drainage around Greenside

Why are we doing flood mitigation after school development?

Could/should have made better decisions

Note: Since development (e.g. school), new areas are flooding and water coming from

new directions

Flood mitigation for school and commercial areas has impacted other (home) area (Ex;

Greenside)

In what ways will the new school access road impact water flow? (worsen?)

Is the School District just doing what the City has permitted? And what now needs to

be done to make that workable?

Concern: Citizen comments re: City’s development discussion not included in the

record

Involvement of School District included in post‐flood assessment?

Note: Packwood gets flood flow! (Was this noted previously?)

Development /decisions made without considering updated data and recent land

use/development

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Rich Clausen ‐ The school site was approved via a Type II plan review. The public

hearing was held on 9/27/10 and included the plans for development of the site. As I

commented in the meeting, minimal public input was provided at the hearing (see the

website at the bottom of this response). There was a comment from the

neighborhood association and there was one neighbor's comments regarding saving

trees, but no comments regarding flooding in the area.

Notice was given to land owners within 250 feet of the subject property and to the

neighborhood association. I say this not in an accusatory manner but simply because I

would be open to suggestions regarding other means of notifying potentially impacted

neighbors of these public hearings. As a Councilor, public input on issues is critical to

making good decisions. And if people don't know that issues are on the table it is hard

to get the feedback.

I would also encourage local involvement in the neighborhood association. The NA is a

tool largely used and listened to by Council. It is an organization established in the City

Charter and is a great point of input for residents of Salem.

School property land use decision:

http://www.cityofsalem.net/CityCouncil/LandUse/Documents/CI ‐TRV ‐SPR‐ ADJ10 ‐

01_Decision.pdf

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Rich Clausen ‐ My understanding of code is that if a develoment meets stormwater

detention requirements, as described previously, it has no grounds to be rejected. I

also understand that current code does not consider downstream impacts of new

development.

Rich Clausen ‐ I have requested that City staff investigate the issues surrounding

stormwater on the new school site. Once their analysis is complete I will be

requesting that the City work with the district to implement plans, if any, to mitigate

stormwater flow.

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Will/how to get feedback to our questions/concerns

Absolute need for both feedback/discussion between City and residents

Value/importance of community connections. Citizen to citizen; city to City

government

Concern: Citizen Emergency Response Team (CERT) did not respond effectively/soon

enough

I still need to follow up on this. At this point I know that CERT helped with some

activities but I'm not sure to what level.

Other

Monitoring Cinnamon LakeRich Clausen ‐ I still need to look into this. I'm not sure how Cinnamon Lake ties into

the existing storm systems.

What factors are affecting water flow? (Flood Ways vs Flood Plains)

Rich Clausen ‐ My understaning is that water flow is affected by the channel that is

used to get the water from point A to point B. A floodway is an identified area of land

that is a pathway for water during a flooding event. A flood plain is a low lying area

that fills with "stagnant" water during a flooding even.

Clogged floodways and restricting stream banks inhibit the water's ability to move and

therefore spread the water over a larger area.

Flood plains can be used to strategically slow water flows down. Note that the size of

the flood event or rain event is critical here. A flood plain capable of detention for a

75 year event will be overwhelmed in a 100 year event. If we want to engineer the

flood plain the larger the event that is planned for, the more expensive the storm

system gets. At this point few of the City's systems are planned to handle a 100 year

event capacity due to budget restrictions See the attached Q&A from the City for

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Rich Clausen ‐ This forum was a perfect setting for the first round of information

gathering. Follow‐up communications, and potentially meetings, will follow as

needed.

I'm seeing that it is evident that we need some communication regarding the current construction project and plans for the Battle Creek basin. Information needs to be

shared as to the extent of what's happening now and some design intent. At this point

I'm not sure how this information should be sent out. I will try get plans and a more

thorough description of the project posted on the City's project page:

http://www.cityofsalem.net/CityCouncil/Pages/SignificantApprovedProjectsStatusRe

port.aspx

Note that the South Gateway Neighborhood Association is the City's official conduit

for communicating with neighbors. I understand that this does not reach everyone in

our area, however I would encourage people to attend these meetings, receive

updates via email, or otherwise be tuned in to these proceedings.

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Woodside / Marstone

Seepage under the house is an annual issue.

Rich Clausen ‐ Thank you for the information. Low lying homes commonly have this

issue and require sump pumps. However, it is important information for others in

similar situations to check below their homes regularly to check for moisture.

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There appears to be fill that is actively dumped at the site across the stream.

Rich Clausen ‐ If there are conerns regarding fill being dumped it would be best to

contact the Public Works office at 503‐588‐6333.

After walking the area with Public Works staff, they will be looking into the situation

and contacting the property owner if needed.

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Waln is flooding annually at Woodside.

Culverts under Woodside appear to be too small, seems to back up annually.

The area is not designated as being in a flood plane.

Detention ponds didn't appear to be collecting water during the flood. Rich Clausen ‐ After walking the area City staff will be reviewing the detention basins and their function.

Closing Woodside during the flood was hard to do but very much needed. When cars

drove through it sent wake into houses.

Rich Clausen ‐ This was a common theme with other areas that were flooded. I will

raise this issue at the City to see if more road closed barricades could be put up during

future flooding events.

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Marstone's issue appeared to be at the storm drain backing up.

Marstone has flooded two years in a row now.

‐ Storm draings are backing up.

‐ City workers were great when they came to clean up last year but why does it keep

flooding?

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Rich Clausen ‐ It appears that the development at Marstone was designed such that

the detention pond is actually in the culdesac itself. As explained in the presentation,

this would explain why the storm drains back up during heavy rain events. Any rain

event over the 5 year mark would result in water pooling in the dead end.

However, this does not explain damage done to homes around the culdesac. After

walking the area I've become concerned with Waln's culvert at Woodside as well as

the coffer dam further downstream. There is a chance these two items may be

causing Waln to back up into the area of the Marstone Ct neighbors. See comments

above.

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Rich Clausen ‐ After walking the area with neighbors I have some questions to ask of

staff. I'm concerned about the culverts under Woodside as well as the ditch that Waln

Creek is relegated to in the area. Also the coffer dam just north of Madras isa

concern to me. As a result of preliminary conversations, staff will make some

operational changes to the culvert at Woodside and analyze the situation further for

possible inclusion as a storm watter capital improvement project.



Q&A-- -Salem Flood of January 2012

The follow ing questions w ere raised by Batt lecreek area residents at the February 7 , 2012,

comm unit y m eetin g. The answ ers have been developed by City staff.

Q. I have heard the January 2012 flood described as a 25-y ear, a 40-y ear, and a 100- year flood eWhat w as it r eally? What does that mean? How w as this different t han the 1996 flood?

At the Salem Airport, 6.1 inches of rain fell during a 48-hour period between January 17 and January 19. Thisthe highest 48-hour rainfall total ever recorded at the Salem Airport and has been determined to be an 80-yeevent for that location. In Salem, an 80-year rainfall event has a 1.25% probability of occurring in any given yOther City-operated rain gauges in Salem experienced even higher rainfall totals, exceeding the estimated 10event (less than 1% probability) for those locations. This heavy rainfall, combined with snow covering alreadysaturated soils in the hills, contributed to floodwaters rising above the 100-year floodplain in several areas. In

contrast, the 1996 flood affected a much wider area of the mid-Willamette Valley. In that event, pre-existing snow, coupled with several days of heavy rain caused widespread flooding from local creeks to the main stemthe Willamette River. The 2012 event was a more localized, very sudden creek-based flood caused by intenserainfall that occurred over a shorter period of time.

Q. What areas of t he city w ere impacted by th e January 2012 f loods?

Among the locations with significant damage were: the area around Salem Hospital; the areas near 14th Streand 21st Street SE; the areas near 13th Street SE, Madras, Fairway Avenue SE and Richmond; the South Gatarea; Eastgate Basin Park area on Hawthorne and Silverton Road; the Mill Creek area off State Street; Hoyt S

area; and the Croisan Creek Road area.

Q. Why was there so much debris in the streams and rivers that blocked flow s?

Whenever streams and rivers rise above the normal high water mark, flows pick up natural and human generdebris from the banks. The larger debris will catch on bridge pilings or culvert inlets and begin to collect smal



Q&A-- -Salem Flood of January 2012

in the drainage basin with rooftops, driveways, sidewalks, parking lots, and streets, will increase the volume orunoff during storm events. The influence that post-1996 development may have had on the 2012 flood is difto determine due to many factors, including the size of the drainage basins, the types of stormwater mitigatio

measures installed, the location of that post-1996 development within a drainage basin, and the volume of raat specific locations within the drainage basin. Post-1996 development represents a small percentage of the tdrainage area has been developed over the past fifteen years

Q. How much did t he tree-cutti ng affect the fl ooding in t he Batt lecreek area?

The drainage basins contributing to flows in the Battlecreek area are quite large and the overall influence of ton the severity of the 2012 flooding is relatively small. Construction of the Waln Creek improvements, the newcollector street, and a new berm around the east and south part of the site required removal of approximatel

trees on the Battlecreek site. In the area adjacent to Waln Creek, many more native trees appropriate to a stside environment will be planted than were removed. Street trees will also be planted along the new street anCommercial Street.

Q. Why wasn’t t he water in t he Batt lecreek area pumped out? I sn’t t here a pump station?

The pump station located on south Commercial Street is exclusively for sanitary sewer flows.

Q. Why did the City n ot f ix t he 1996 Batt lecreek flooding problem and allow constr uction of t he

school? How mu ch did the new school contri bute to t he flooding?

Salem purchased the property to provide additional park/open space and to improve this section of the Battlestormwater system because of the 1996 flood. The S-K School District’s interest in a portion of the property mSalem’s purchase of the north 30 acres financially feasible. To improve the site’s capacity to hold stormwater,Creek will be reconfigured and an adjacent flood storage area will be constructed. This work, along with remotwo existing culverts within the site along Battle Creek, will provide some additional water storage on the site

Battle Creek Flood Communication

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