For the last year or so, we have been working on a program
geared towards younger audiences between the ages of 6 and 18.
We think it is really important for them to understand the water
situation, as they are the future.
What are some research issues that will help expand
the implementation of potable reuse?
There are a couple of areas which will be helpful: research
on public outreach as well as public acceptance, research
that is associated with the feasibility of direct potable
reuse, and research about regulatory acceptance.
How is San Diego Public Utilities distinguishing
between indirect and direct potable reuse?
For indirect, the purified water is treated and then goes to
a very large reservoir where it mixes with runoff from rain
as well as imported water. It then goes to a water treatment plant before going to our customers’ homes and
businesses. Direct basically skips the reservoir step and
takes the water directly to a water treatment plant.
We actually have some research underway presently in
San Diego on two additional treatment steps that could
replace the environmental buffer, which is the reservoir,
so we are doing some direct potable reuse testing.
How do you balance potable reuse with other supply
In terms of pursuing potable reuse, what we would really like to
do is reduce the total amount of water that we import, which
is about 85%, and be a little bit more water independent. That
really resonates with local officials as well as the general popu-
lation. Right now, it is a bit of a precarious situation in California
with all of the cutbacks. We have no control over that, so the
idea of creating your own local water supply is very appealing.
How our system works, and the commitment that we have
made in the past, is that the majority of the water we buy is
untreated, or raw, water because we have three water treat-
ment plants. There are a lot of other water agencies in the
region that buy treated water. We also have a desalinization
plant that is coming on line. We have a small portion of our
service territory that is not connected with our treated water
system, so the desalinated water basically will be the treated
water for that area. We are estimating that this represents
about 3% of our total water supply; the rest of our service
territory is served by our three water treatment plants. So
it is kind of an easy decision to make, we just buy enough
of the desalinated water to equal our treated water needs.
How do you balance developing new supplies with
demand management activities?
We are at the end of an imported water pipeline so we have
been pretty aggressive at pursuing demand management
over the course of the last 20 years. For example, our water
sales are the same amount as they were 30 years ago. We
attribute that to water conservation. We have had population growth of about 400,000 people and we are selling the
same amount of water. What we are pursuing is working.
If the current drought subsides in the next year
or two, how will that impact your planning?
It wouldn’t. We would still be pursuing exactly what we are
currently pursuing. We do long-range water resource supply
planning; we update our planning document every five to
10 years and most recently completed it in December of last
year. Since we import 85% of our water, we are very keen on
water conservation. At the end, in 2035, we could be creating enough water supply to equal about 30%. We recognize,
because of the situation where we are in Southern California,
and because we are at the end of an imported water pipeline, that there is no one magic solution; we need all of it.