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Discharging from Lake Sonoma

My understanding of discharges from L. Sonoma is that it is “surface water”, and cannot directly enter the SCWA pipeline system without treatment.

So far, to get their additional 26,000af, this means
(1) release down Dry Creek in a new pipeline, to diffusers within the gravel-bed aquifer of the Russian, for collection at the Raney collectors downstream.
– this alternative (last estimated costs I heard was in the 500M range) is problematic for SCWA, since it releases water into the river significantly above its pumps, allowing “other straws” to pump that water before it gets to the Raney collectors.  SCWA is loathe to allow others to do that.

(2) the water could go down Dry Creek in a pipeline, but into a water treatment plant, which would allow all the water to then be fed directly into the SCWA plumbing, with no losses to others downstream.  However, the estimated costs for a treatment plant are in the 1-1.5B+ range.  Oops. Very expensive.

(3) SCWA did a preliminary plan (around 1995??) to pump water over the back of L. Sonoma, and down a pipeline to the Alexander Valley, where their scheme also included injection into the groundwater table there for withdrawal during dry months.  I found some documentation on that, and asked that the Water Project EIR address that option.

I’d expect that SCWA will look for federal money to help them out (yeah, to save the fish and other SCWA environmental achievements).

We won’t know what the choices will be til after the DEIR for the Water Project is released in another year or so.  Unless the process of opening up D1610 holds it all up.

of course, it might be possible to save enough water to avoid new demands for another 20 years.  But that requires SCWA to relinquish the opportunity to sell more water, both new and used.  Yup, the Russian River = SCWA Income Stream.

David

Theories on mercury and MTBE-

-I don’t believe that the mercury in the lake rises in concentration to an actionable level to require treatment for use as a piped water supply.
I did hear a portion of a KZYX/Z community radio news report with a regional water control agency rep in the past two months discussing mercury in lakes Sonoma, Mendocino, and Pillsbury, in regard to a study that was being launched to determine the sources of the mercury, including atmospheric migration.
In the past I learned the mercury issue with contaminated often older fish, is because of the vegetation consumed by the fish results in bio-concentration from the organic mercury methyl-ation process.  The water is safe to drink.

-MTBE is apparently difficult to remove from water I recall from a couple of years ago, but in a lake environment it tends to pool in a layer and concentrate at some elevation within the reservoir.  Therefore if the water service pipe intake level were adjustable, it might be possible to avoid most of it during much of the dry season serving the SCWA.

Likewise since additional quantities of MTBE, now a banned substance, are not coming into the lake unless there is some delayed percolation release, it might be possible at the end of the dry season as the weather cools, to suck out the layered pooled fraction with the same water service pipe detached to discharge into the main stem Russian just before heavy winter rainfall mixing disturbs the MTBE layer in the lake.  This process may take several years to approximately fully flush the lake.

As the water level goes lower with releases from Lake Mendocino, where I seem to recall that an MTBE layered pool has been characterized in the past, I haven’t heard of any concerns with MTBE affecting the fish in the river, although at some point the oxygen goes too low in the lake, at least that is what the officials say, and there is a die off of a certain large fish species.

–  Eric Sunswheat

On 9/11/07, sjfr2@aol.com wrote:
And since this will be surface water (with mercury and MTBE), it will need treatment before it can be piped into the SCWA distribution system.

Stephen

You know what this is about don’t you????

SCWA want to release large amount into Dry Creek for diversion later down stream.

NMFS says no – it would hurt fish.

SCWA is looking for a way around.

We need to make sure NMFS holds their ground. and diverted water goes through a pipeline – if it goes.