[FWD: Wilderness Rim flooding]

It looked to me like the consensus at the meeting at the fire station was that the community preferred a drain pipe to remove water and prevent flooding.

Since one challenge will be the politics with Seattle Water, I contacted Kathy Lambert's office to see if they'd help advocate for us if the feasibility study showed that option was do-able.

First the message I wrote, and below that the response.

From: Dan Covey <dan@dancovey.net>
Date: September 15, 2011 8:42:29 AM PDT
To: "Lambert, Kathy" <Kathy.Lambert@kingcounty.gov>
Cc: Dan Covey <dan@dancovey.net>
Subject: Wilderness Rim Flooding Meeting 9-14

Dear Mrs. Lambert,

Thank you and your team for sending a representative from your office to attend the community meeting at the Wilderness Rim Fire station last night to listen to feedback on flooding mitigation in our neighborhood.

I brought my father-in-law with me, he is a semi-retired civil engineer with more than 35 years of experience designing fresh and waste water projects worldwide, and he has worked extensively with the Seattle Water department.  We took a look at the Brewster Lake drainage and the greenbelt flood areas prior to the meeting and I would like to share a little of his expertise, and a few key points.

Any project designed to increase the holding capacity for Brewster Lake overflow in the greenbelt area will be ineffective due to ground saturation.  I almost bought one of the houses the county purchased and demolished, and when we looked at the house on in October 2003, it was lightly raining, the back yard was so saturated with water is was like walking on a sponge.  My point being the water table is so high in this area, you can dig all the holes you want to hold water, but they'll fill up with ground-water before the overflow from the lake has a chance to use this proposed excess capacity.  I'm afraid this, as well as the proposals to construct berms or flood-walls around at risk homes, that water will seep under, and which would require high capacity pumps would not be an effective use of limited monies available. 

The best technical solution is a gravity overflow drain from Brewster lake to the hillside above Rattlesnake lake.  This is a proposal the county is looking at, but we were told that the biggest obstacle to that plan is getting permission from Seattle Water to discharge into their watershed.  The city should be reminded that when they built Chester Morris, they raised the water-table in our area significantly, the current site of Rattlesnake lake was once a railroad town, that flooded when the damn was installed.  In the winter when Rattlesnake lake is very low, you can walk down about 30 feet and see some evidence of where that town used to be.

Because the water table is higher, it puts more pressure on the drainage capacity of the depression our neighborhood is in.  There seemed to be a consensus at the meeting last night that we'd like to see a drain pipe solution pursued, and we will need your help with Seattle Water to convince them to support this project.

A drain pipe would cost between $500k and $750k complete, which is about what I heard the county can budget over three years for flood water mitigation in our neighborhood, and would be a permanent solution.

Best regards,
Dan Covey MPM, PMP
425-785-4217

If Ability is the Engine, Attitude is the Transmission.

-------- Original Message --------
Subject: Wilderness Rim flooding
From: <grace.reamer@kingcounty.gov>
Date: Thu, September 15, 2011 3:22 pm
To: <dan@dancovey.net>
Cc: <wendy.kara@kingcounty.gov>, <kathy.lambert@kingcounty.gov>,
<christine.jensen@kingcounty.gov>

 

September 15, 2011

 

 

Dear Mr. Covey,

 

Thank you for contacting King County Councilmember Kathy Lambert and for participating in last night's meeting about Wilderness Rim flooding issues and how we can work together to design a solution that will last into the future. We certainly understand your concerns about the evidence of a high water table and how that contributes to flooding with the addition of storm event overflow from Brewster Lake. We expect that the engineers in the Water and Land Resources Division will keep your comments in mind as they continue with hydrology studies to help us better understand the interaction of groundwater and surface water drainage in the Rim area. And we will be glad to assist with negotiations with the City of Seattle, if needed, regarding the redirection of floodwater from the infiltration area.

 

Again, thank you for taking the time to contact Councilmember Lambert about this issue. Please keep us informed about your concerns and contact us at any time if we can be of assistance. 

 

Sincerely,

 

Grace Reamer

Legislative Aide

King County Councilmember Kathy Lambert

District 3

(206) 296-0331

grace.reamer@kingcounty.gov

 

This email and any response to it constitute a public record and may be subject to public disclosure.