From: Chiye Azuma
Sent: Thursday, December 09, 2004 12:09 AM
To: Ward, Ron (PWA)
Cc: Mark Brest van Kempen; dchapman@desilvagroup.com; kpeyton@DeSilvagates.com; gantenbein@n-h-i.org; Office of the Mayor; tcaspers@cctimes.com; Neary, Mike; lcasey@angnewspapers.com; nannystu@pacbell.net; khl@rb2.swrcb.ca.gov; Schwarz, Alison; Estes, Lesley; Uzegbu, Marcel; Nadel, Nancy; Brooks, Desley; Peggy Stinnett; contact@chimescreek.info
Subject: Re: increased flow in creek
Ron,
I just wanted to clarify with you some observations over the past month:
Contrary to your assertion that no overflow has occurred from the detentionbasin, on Nov 11, 2004 during the last major storm event, Mark Brest vanKempen and I observed overflow from the filtration facilities at the project site. The photos in the album labeled "Leona Quarry Nov 11, 2004" at http://community.webshots.com/user/chimescreek show the main detention pond and the dark ring marking how high the water rose before the contractor started to pump the water into the temporary siltation pond and into the baker tanks. If you are interested, I also have a video that shows the temporary siltation pond being overwhelmed and starting to spill over (water appeared to be fairly clear) while the baker tanks were also discharging unfiltered dirty water into the city storm drain because they were unable to keep up with the influx from the subdrains and from the main detention pond. I understand that the detention pond has been unable to cope with the rainfall that we have been enjoying for the past day or so, filling up much too quickly to the upper orifice. It would appear that some dredging of the accumulated silt may help to increase the capacity?
You've been telling us that the 39" pipe under 580 fwy has been left intact; therefore the flow to the creek remains unaltered. Then why is the discharge pipe from the detention pond orifice designed at 45"? How do you account for the other 5 discharge points from the project site that completely bypass the detention pond and do not figure into the calculation?
The concrete v-ditches that feed into the 3 storm drains at the northwest side of the site do not even appear on the final map that the City Council is being asked to approve. Why is this runoff not channeled into the detention basin so that it, too, can be controlled and filtered?
As you may recall, at the recent stormwater management workshop sponsored by the Alameda County Clean Water Program that you and I, and many others from the City of Oakland Public Works attended, Gary Palhegyi of GeoSyntec Consultants gave a presentation based on a three watershed study conducted for Santa Clara on hydromodification management. Contrary to your assertion that Chimes Creek is being protected because the project is controlling storm water runoff peak flows, Gary 's study concluded that it is the increase in duration, volume and frequency of runoff resulting from urban development, i.e. increase in impermeable surfaces, that cause the long term and permanent damage to our waterways. The study's coauthors include Balance Hydrologics and Phillip Williams & Associates, familiar names as they are your peer reviewers and "experts" for the Quarry project.
Although Mr Palhegyi's study was based on case studies of watersheds elsewhere in the State, the continuing degradation of Chimes Creek is a classic example of hydromodification caused by urban development. The sewer pipe that spilled raw sewage this past weekend near Nairobi and Hillmont (also refer to pictures posted at http://community.webshots.com/user/chimescreek) is an ongoing problem that the City's Maintenance Department has been desperately patching up since the late 1980's.
How is this sewer pipe related to the project? This is the 8" pipe line that has been designated to carry the waste load of 400 plus new residential units at Leona Quarry. (Will the residents be asked to take turns flushing?) This is the pipe line that my 50 foot Acacia tree will soon crash into, as the soil surrounding the root ball is eroding away from the increased frequency, volume and duration of runoff from the project; just as the Walnut Tree opposite the exposed pipe toppled over and across the creek 16 years ago, causing a cavernous erosion that exposed the sewer line. When did the Ridgemont development alter this watershed? About 20 years ago. It doesn't take much to connect the dots.
This is the pipe line that the City's maintenance crew refer to as a "dead horse that can't be fixed," yet they keep coming back year after year to respond to emergency calls to apply some bandages and more rope to tie to whatever remains on the eroding banks. This is the pipe that will hopefully get some of the $400,000 that Mr Godinez so proudly says the developer has contributed towards upgrading the sewer line, afterall, it has been more than 16 years. This is the pipe that Mr Uzegbu has said could be fixed without disturbing the creek. The pipe levitates 8 feet above the creek bed and the City has only a 5 foot easement, total. That's 2 and one-half feet on either side of the pipe. How will Mr. Uzegbu acccomplish his task without disturbing this creek? Are there plans to culvert, channel, or widen the creek? If so, please let us know. As far as County Flood Control is concerned, the creek is private property, so we property owners need to know if the City has any intention of condemning parts of our properties.
I thank you for your response to our concerns, and hope that you can provide answers that will assure us that you are also looking out for our interests in the downstream community.
Chiye Azuma