Increasing San Diego's Water Supply

Written by  Hillary Shipps
Rate this item
(2 votes)

There are a number of ways to expand water supply in San Diego. San Diego Coastkeeper supports following the route of reduce, reuse, recycle, before attempting to find new sources.

Reduce:

20GallonChallenge

First and foremost, we need to focus more on water conservation, or reducing the amount of water we actually use.  It’s the easiest, cheapest way to boost our water supply.  It is also the focus of the Be Water Wise 20 Gallon Challenge, a campaign to reduce the amount of water used per household by 20 gallons per day.  Conservation techniques can include anything from taking shorter showers to starting a compost bin so you use less water running the disposal and much more.

 

Reuse:
rainwater_harvestingRainwater harvesting and greywater systems reuse water without treating it first. This is also a fairly simple way to increase supply, because less water is wasted. Capturing rainwater allows its use for irrigation and helps avoid using potable water for the purpose. It’s easily done at home, and requires very little installation.  

Greywater also can be used for irrigation, with the added bonus of reducing the amount of water sent to treatment plants and released into the ocean. Using greywater at home is more complicated than catching rainwater, as it requires a plumber to divert water exiting bathroom sinks, washing machines, and showers (all with very low dirt-to-water ratios) to landscaping outside the house (storage of greywater is not advised).  The low level of detergents and dirt can actually be good for the plants, but keep it on your property and avoid runoff to the street.

Recycle:
Wastewater recycling, or Indirect Potable Reuse (IPR) if used for drinking water, falls into this category. Sometimes called “toilet to tap” by detractors, the process uses advanced treatment processes to treat wastewater to levels even cleaner (page 108 of this report) than San Diego’s typical drinking water, then put it back in the water supply. A Demonstration Project is underway to prove the process safe for San Diego.  If it succeeds, wastewater recycling could be the next step in increasing our water supply.  

Purple pipe is the other side of wastewater recycling, where wastewater is only partially treated and used for irrigation.  Coastkeeper is in favor of this strategy only in targeted areas, as it requires a separate plumbing system and is therefore very expensive to install.  

New Sources:
After experimentation with the above sources, it might be necessary to look for new water sources.  Further importation of water is theoretically possible, but San Diego already imports more than 80 percent of its water from the Sacramento/San Joaquin Delta and the Colorado River, supplies not under our control.  Increasing that percentage would be risky, so any further imports would have to be done in combination with other techniques.  

bbc_sydney_desalDesalination is another option, but while local, this source of water has a number of problems. A major one is the intake pipe: open-ocean intakes function as vacuums into the sea or lagoons where they suck in and kill marine life, a major issue.  Subsurface intakes are better, as they take in salt water from under the sand and so greatly limit fish kills.  The process of desalting ocean water is very similar to Indirect Potable Reuse, but because of the higher salt content, it is very energy-intensive.  Besides the desired freshwater, the process also yields a very saline chemical-laden brine – diluted, the brine can be released into the ocean, but it can poison marine life if too concentrated. Menachem Elimelech, director of the environmental engineering program at Yale, said in a News Hour interview, “Desalination of seawater, because it is energy intensive should always be as a last resort….  It can be and should be part of the portfolio for water supply but only after all other measures are done.”  Coastkeeper believes that desalination could have a place in San Diego’s water portfolio, but only on a limited scale and only using subsurface intakes.

Read 2306 times

Leave a comment

Make sure you enter the (*) required information where indicated. HTML code is not allowed.

Take Action

Donate Now

Donate to San Diego Coastkeeper

Donate to San Diego Coastkeeper

With you, we can protect San Diego’s aquatic playgrounds. Gifts of every size help us defend your salty seas and beautiful bays. From test tubes in our lab to hands-on...

Read more

Become a Member

IMG_7706

Start Coastkeeping. Become a member today and protect and restore swimmable, fishable and drinkable waters in San Diego County.

 

Report a Problem

plastic-beach-feat
Catch the Polluters

If you see someone pollute, report it to Coastkeeper. Let us help you protect your waters.

Attend an Event

Jul
18

9:00 am - 11:00 am

Jul
18

11:00 am - 3:00 pm

Jul
25

9:00 am - 11:00 am

Aug
8

9:00 am - 11:00 am

Aug
15

9:00 am - 1:00 pm

Aug
22

9:00 am - 11:00 am

Sep
19

9:00 am - 12:00 pm

Get the News

Read our Blog

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
Prev Next

Meet The Coastal Champions of 2015

Meet The Coastal Champions of 2015

This year is our 20th anniversary and we are proud to announce the Coastal Champions on World Oceans Day. These individuals, organizations and businesses have helped ensure that San Diego...

Our Kids Love “Gross Stuff” And That Mak…

Our Kids Love “Gross Stuff” And That Makes Me Happy

Haley Cahill was our education intern from January to June 2015. She is majoring in Environmental Studies at the University of San Diego and believes the answer to improving many...

The Water War For Lake Mead

The Water War For Lake Mead

Formerly America’s largest reservoir, providing water for 20 million people in Arizona, Nevada and California, Lake Mead hit a historic low on April 30. This low wasn’t an inevitability of...

20 Years is Celebrateable

20 Years is Celebrateable

It’s been twenty years since two gutsy water lovers took action to stop the toxic dumping that was slowly killing San Diego Bay. In 1995, they created San Diego Baykeeper...

The Ocean Enthusiasts of Coronado Middle…

The Ocean Enthusiasts of Coronado Middle School

An important step in protecting and restoring fishable, swimmable, drinkable water is making sure we have informed and passionate leaders in the next generation to which we can hand off...

Water Quality 2014 - More Impacts from t…

Water Quality 2014 - More Impacts from the Drought

In 2014: Looks like San Diego's drought affects more than water quantity—and we have the data to show it. We proudly announce the results of our 2014 Water Quality Monitoring efforts, and...

Water Quality 2014: San Luis Rey Watersh…

Water Quality 2014: San Luis Rey Watershed

Water Quality Index Score: 77, Fair We tracked two parameters of concern in San Luis Rey Watershed: Turbidity: Two-thirds of the turbidity samples exceeded healthy standards Levels of pH: Over half of the...

Water Quality 2014: Carlsbad Watershed

Water Quality 2014: Carlsbad Watershed

Water Quality Index Score: 72, Fair To no surprise, our 2014 data showed that: Nitrate is consistently high in upper Escondido Creek In fact, four of the five samples with the highest nitrate...

Water Quality 2014: San Dieguito Watersh…

Water Quality 2014: San Dieguito Watershed

Water Quality Index Score: 76, Fair Our data in San Dieguito Watershed show: Ammonia, phosphorus, and turbidity measuring at marginal on our Water Quality Index Scores Ammonia and phosphorus are nutrients. In the...

Water Quality 2014: Los Peñasquitos Wate…

Water Quality 2014: Los Peñasquitos Watershed

Water Quality Index Score: 76, Fair Well, here it is: the most typical, average watershed in San Diego County in terms of water quality pollution and health. Our data in this...

  • Video
  • Facebook Fans
Join Our Newsletter
  • EarthShare_Californiaweb

SAN DIEGO COASTKEEPER
2825 Dewey Rd., Ste. 200 • San Diego CA 92106 • TEL. 619.758.7743