The Eastern Municipal Water District (EMWD) is experiencing rapid growth and
development. To date, the District obtains most of its potable water supply as treated water
from the Metropolitan Water District of Southern California (MWD). In an attempt to reduce
the reliability on MWD supplies and to meet the anticipated potable water demands, EMWD
embarked on a fast-track project in 2000 to provide an additional 10 mgd of water to its
system as soon as possible. The plant would be master planned to 50 mgd of capacity.
The project involved the construction of a new membrane treatment facility at an existing
pumping station that was used to pump Colorado River Water (CRW) into the system
supply many years ago. Source water for the new treatment plant will initially be CRW off
the existing MWD aqueduct. In the future, there is a possibility of State Project Water and
even water from nearby Lake Perris being delivered to the plant as source water.
Due to the fast-track nature of the project there was no time to pilot test treatment
alternatives. An evaluation was carried out that determined that membrane filtration would
offer the most flexibility for EMWD to treat both present and future raw water supplies and
meet both present and future water quality regulations. Zenon was chosen as the
membrane system supplier and the membrane system design incorporates a novel
declining flux arrangement that allows for high water recovery. It also incorporates the
ability to periodically reverse the raw water flow direction (and tapered flux) to allow the tail-
end membranes to be exposed to cleaner feed water. This should improve membrane
performance and reduce cleaning requirements. The plant layout includes space for future
chemical pre-treatment and PAC addition, should this be required. Includes table, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 670 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 10 |
| Published : | 03/05/2003 |
