ENVIRONMENTAL CONSIDERATIONS

Click here to view a March 2004 report by the California Coastal Commission titled Seawater Desalination and the Coastal Commission Act.

The MMWD has issued an extensive Environmental Impact Report.
Click here to link to the index of that report. It, in turn, has links on their web site to the many chapters in the report.

The author of this site has no comments on this Environmental Report - other than that it appears quite complete for the subjects reported upon.

However, this web site contains several items of possible interest relative to other alternatives which were not reported upon. (The staff of the MMWD is not to be criticized for not considering them since they may be viewed as "Out of the Box" concepts, items not normally under the purview of theMMWD as a separate District.

These include:

ADDITIONAL SEWAGE RECYCLE

Not discussed is the fact that our sewage streams have a very low salinity, as demonstrated by the fact that it is used for landscape irrigation to the extent that it is currently. The discharge from the San Rafael treatment plant - which the MMWD proposed to use to dilute its brine discharge, has a dry weather flow rate of 8 MGD and a wet weather flow rate of 115 MGD. Use of this as a feed to the Reverse Osmosis plant would substantially reduce the power requirements and would likely substantially reduce the pretreatment facilities. However, it would require re-introduction of the product water at the remote storage lakes in lieu of shorter connections to existing storage tanks, and might require some additional testing. This is not new technology and is being considered elsewhere in Califonia. There are of course significant hurdles to overcome in considering this route - see the section on OPTIONS / Recycling.

ALTERNATE TECHNOLOGIES

Possible use of solar thermal panels for pre-heating the inlet water - which lowers the viscosity of the water, increasing the permeablity through the reverse osmosis membranes, and decreasing pumping power requirements.

ALTERNATE SITING

Location further up the San Pablo Bay to take advantage of lower salinity (valid only during wet years) and possibly to conduct a joint activity with the North Marin Water District who will also be looking for new sources.

BUY-OUT of WATER RIGHTS to REDUCE FUTURE PROPERTY DEVELOPMENTS

Use our precedence in reducing further property development by aquition of Open Space and the MALT program which bought out development rights on West Marin farms. This might involve a much more substantive increase in the MMWD upper tier rates so as to provide a surplus of funds that could be used to Buy Out all, or most of, the water rights on as yet undeveloped property, leaving the owners the option of building facilities that have no, or very low, water requirements. See OPTIONS / Stop Development.