East Bay Municipal Utilities District (EBMUD), Contra Costa Water District (CCWD), San
Francisco Public Utilities Commission (SFPUC), and Santa Clara Valley Water District (SCVWD)
are joining forces to investigate desalination as a potential regional solution to water supply
reliability. To enhance their dry year supplies, the Partner Agencies are conducting studies that
could result in one or more regional desalination facilities with an ultimate total capacity of up to
71-mgd in Northern California.
One of the challenges for this project is unique water quality. The site selected for pilot testing is
the estuarine junction of the San Francisco Bay and its freshwater tributaries, where raw water
salinity can fluctuate by an order of magnitude on a tidal and seasonal basis. Traditional
membrane technologies for desalination have been developed to treat either brackish water or
seawater. These coarse classifications can be applied when raw water quality can be
categorized as one or the other, but are less readily applicable in surface waters with significant
tidal influence.
In order to address fluctuating water quality with the available suite of membrane technologies,
several innovative design approaches have been selected for pilot testing. Three desalination
trains are being operated in parallel, integrating a variety of membrane type configurations
including nanofiltration (NF), brackish water, and seawater elements in one-stage and two-stage configurations.
The objective of pilot testing is to determine the efficacy of each configuration with respect to feed
water quality, process efficiency, and long-term operation.
Pilot testing is underway and will continue through early 2009. The side-by-side comparison of
three different treatment approaches during this pilot study will generate valuable information for
the water industry. Detailed findings are presented to highlight treatment efficiencies and
operational experiences in evaluating the performance of various membrane configurations in
tidally fluctuating feed water quality. Includes tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 1.1 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 15 |
| Published : | 11/01/2009 |
