Water Quality Issues:
Salinity, Toxins and other effects of Delta Water Exports
Click on the maps
below to see larger versions of each map. The first two maps show the
occasional salinity intrusion into the Delta over two periods of time.
Prior to 1943 the Delta's fresh water might get higher salinity from mixing
with the saltwater of the San Francisco Bay if it was a really dry year.
After the Federally-funded State Water Project was completed, as part of the
agreement between the governmental agencies and the Delta landowners,
salinity intrusion into the Delta was limited to a specific area. To
keep salinity at or below the "x2" mixing area, fresh water was released
from the damns that had been constructed that was withholding fresh water
that would normally flow through the Delta. Look at maps representing
water quality studies over the last 50 years and you will see that a very
basic rule is evident: The Delta has fresh water and flows from the
rivers and streams above the Delta must be allowed to continue to stop
saltwater intrusion into the Delta.
Water quality
and flow is also very closely related to the decline if native fish
populations of the Delta; hense the volume of reports and studies on
fish! To see the studies that generated
the maps, go to the different links on the left, by year or time period of
Delta history.
