8/30/07. Have you seen all the digging activity along the Sammamish River south of City Hall lately? It's not just about "IMPROVEMENT FOR FISH AND PEOPLE" . Some of that work ($1.7 million) in the vicinity of Lukc McRedmond Park is the first step toward building Redmond's ambitious regional downtown stormwater treatment system.
Jon Spangler, Redmond Division Manager of Stormwater Management gave a presentation in July to the King County Water Quality Committee about Redmond's $40 million regional stormwater treatment plan for downtown Redmond. Click on the following link to find the video archive:
Regional Water Quality Program, 7/25 - Redmond Stormwater (Real One media suggested)
The Regional treatment plan is a huge, proactive undertaking designed to service over 500 acres of downtown development anticipated in the next 40-50 years. It involves building 6 large "outfall" treatment facilities rather than hundreds of smaller vaults. Large trunk lines the length of Redmond Way and on 85th Street will be dug with pipes installed. Planned road re-designs will probably be coordinated with the storm pipe installation. All six facilities will be built in five years. Click here for the stormwater facility map
The $40 million cost will be paid by 1) raising residential and commercial stormwater fees by 40% and 2) raising the capital connection fees from $900 to $4000. According to Spangler, the city is well funded and Redmond already has one of the highest stormwater rates. Our rates are about double Seattle's rates.
If you look carefully at your 2007 utility bill you will probably find an additional $6.58/month charge. It goes towards the new regional stormwater system. It appears Education Hill, North Redmond, Grass Lawn and other neighborhoods are now paying higher stormwater rates to help fund the DT regional system.
Spangler states that about 90% of Redmond stormwater drains into the Sammamish and everyone benefits from a healthy downtown.
For the downtown property developers the regional plan is a deal.
- $800,000/year savings is anticipated over the old site by site stormwater design. Spangler claims the regional plan is about 60% the cost.
- The regional system doesn't consume landowner's buildable land.
- Maintenance costs will be reduced since catch basins won't need to be cleaned 1 month every other year along Redmond Way; and no catch basins to vacuum at night when it's dangerous to workers.
All wastewater treatment will take place "at the end of the pipe" into the Sammamish River OR Bear Creek. End-of-pipe treatment is least desirable of all treatments, though Spangler says Ecology feels they have more control over overall water quality.
The 2009 "Safeway-Bear Creek" outfall underground facility ($7M) will direct discharge into Bear Creek without detention. WILL EXTRA PRECAUTIONS & TREATMENTS OCCUR HERE? The remaining 5 facilities are expected to be built by 2011 or 2012 and all 5 will direct discharge into the Sammamish River without detention, as follows:
- 2007. Luke McRedmond underground facility ($1.7M) -- under construction w/ habitat upgrades
- 2009. The 8oth Street Trunk underground facility ($7.6M)
- 2011. Redmond Way Storm Trunk ($22M) -- start in 2009
- 2010. Redmond Way Trunk ($4.5M) -- wetland treatment
- 2008. Leary Way ($5.8M) -- natural vegetation for treatment
The 6 facilities will monitor flows and treat the run-off water by using: 1) a swirl concentrator to remove the large debris and 2) media filters to remove contaminants. Spangler isn't sure if he will use bio-filters on the end. Just how effective will this "1-2 swirl/media punch" be to keep the Sammamish fish and our recreation healthy? We need to keep an eye on this. Spangler described a "water-oil separator" that would be used at a downtown branch. He indicated treatment wetlands and sand filters may be used.
WILL REDMOND'S ADOPTED 2005 DEPT. OF ECOLOGY TREATMENT STANDARDS GUARANTEE THE FISHABLE, SWIMMABLE, RECREATIONAL WATERS WE NOW ENJOY? -------------------------------------------------------------------------------------------------------------------
A county representative asked Spangler about the impacts of Microsoft's growth on our stormwater run-off. Mr. Spangler plans to build a separate regional stormwater system for the Overlake Urban area to service Microsoft & environs. Treated stormwater will be discharged into Bellevue's Kelsey Creek system.
Without a regional Overlake stormwater system, the "Block C" development of Microsoft would require 14 vaults each 700,000 cu. ft. in size! That's 3x the volume of City Hall. (Our wellhead protection officer also claimed removal of 3x the volume of City Hall in contaminated by hazardous waste. ) Our super-sized City Hall is drawing lots of attention these days. Thus, Overlake Urban Center will probably install a regional system -- the good news is Microsoft will apparently pay for most of it.
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FACTOIDS:
1) did you know stormwater was not regulated for effective treatment until after 1987? Expensive stormwater treatment retrofits are required on redevelopments prior to 1987.
2) the largest contributor to fecal coliform in Seattle is non-waterfowl birds and rodents.
3) 25% of all land-use in Seattle are roads, highways & road shoulders! Some of the worst pollutants come from roadway stormwater. This does not include parking lots.
4) The Sammamish River reaches a low of 17 feet in summer and high of 28 feet in winter, thus gravity flow of downtown stormwater a challenge. DT Redmond is 35-40 feet above sea level. Gravity flow of our stormwater is not 'strong'.
5) Redmond's downtown aquifer is sometimes 5-7 feet below the surface in the winter making installation of infrastructure challenging.
6) It's estimated that 15 acres of our downtown will be developed each year. With 520 acres of developable land it will take about 40-50 years to develop our "downtown".
7) Redmond's stormwater treatment standards are higher than Bellevue's so Bellevue becomes the limiting factor to overall water quality. They need to get up to speed!
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