Biology Reference
In-Depth Information
DIABLO COOL
A local leader in industrial water conservation is the Delta Diablo Sanitation
District in the Pittsburg-Antioch area. The district now uses 2.8 billion gallons
of recycled water to cool its power plants and water 20 acres of parks and
landscaping every year, making this the largest recycled water project in the
state. The process spares potable delta water for other uses, and it eliminates
the effects of warm-water discharges on fish.
Over the last quarter century, Los Angeles's Metropolitan Water District
has paid out $220 million worth in incentives, leading to the production of
1.2 million acre-feet of recycled water. In recent years, the six counties at
the heart of the district recycled about 155,000 acre-feet annually.
The temperate Bay Area also undertook conservation and recycling
projects during droughts, but at a less urgent pace than hot, dry southern
California. The Bay Area isn't an egregious water waster. Between 1986
and 2004, the region's population grew by almost 21 percent, but total
water use only increased by 3 percent. Since then, conservation measures
have included weather-based irrigation management, public outreach to
urban gardening groups, water saving messaging, washing machine re-
bates, and landscape surveys to help schools and businesses better budget
their water. More recently, interagency partners have been examining op-
portunities for regional conservation across city and county borders, in-
cluding ways to reduce the miles water must travel from supply to de-
mand. Because two-thirds of the Bay Area's water comes from outside the
region, and California uses a lot of energy redistributing water, reusing
local supplies can save gallons, gigawatts, and greenhouse gases.
“Recycled water is a drought proof source of supply,” writes David
Carle, author of
Water in California
. Unfortunately, recycled water only
accounted for about 3 percent of Bay Area water supplies in 2007. To date,
around half of the 40 wastewater treatment facilities in the Bay Area are
recycling a portion of their flow for beneficial uses, according to RMC's
Randy Raines. He estimates that, as of 2010, about 35,000 acre-feet of re-
cycled water were being delivered via purple pipes to golf courses, parks,
soccer fields, and car washes every year.
In 1999, Bay Area agencies produced a regional master plan for recy-
cling. In a recent update, Raines estimated the regional approach could
generate 150,000 acre-feet per year of new supply by 2030. The more recy-
cling done, the more the bay and the fish in its watershed will benefit from
both reduced demand on “pristine” source water and cleaner wastewater
discharges. “In today's world no one thinks twice about recycling solid
waste, but recycling water just isn't there yet,” says Raines. “Growing pub-
lic support of environmental quality will make it happen soon.”
