Increasing San Diego’s Water Supply

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.


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

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.

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.  

Desalination 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.

Eat Your Way to a Healthy Planet

I love cheeseburgers. Hodad’s, Rocky’s, Five Guys … they’re all my favorites.  But for next week, I’ve decided to drop the burgers and go vegetarian during San Diego Veg Week. I invite you to join me and several other staff members here at San Diego Coastkeeper as we go meatless from September 25-October 2.

Here are 5 ways that eating vegetarian can help protect the environment:

  1. It takes 12,009 gallons of water to produce a pound of beef.  That means you can  save more water by forgoing one pound of beef, or four hamburgers, than by not showering for a year.
  2. Concentrated Animal Feeding Operations, or “CAFOs” are a major source of water pollution around the country.  Animal waste and feed cropland dump more pollutants into our waterways than all other human activities combined.
  3. Meat production is a major contributor to the “dead zone” in the Gulf of Mexico—7,000 square miles where dissolved oxygen in the water is too low to support marine life.
  4. Cow farts are a major source of methane, a potent greenhouse gas.By passing on the burger, you can reduce your contribution to global climate change.
  5. Nearly half the water consumed in this country and 70 percent of the grain grown is used for livestock, mostly cattle.

Indirect Potable Re-Use: It Works!

In an attempt to solve its water crisis, San Diego has explored several alternatives that include sea water desalination, water recycling and Indirect Potable Re-use (IPR). Out of all these, IPR provides the best results.   

Desalination may seem like a good idea because the ocean is so vast, but it’s expensive and energy intensive, ranking it low on the sustainability scale.

Water recycling, or “purple pipe” systems, cleans waste water enough so that we can spray it on our lawns and golf courses. The non-potable water is not meant for human consumption or to replenish any of our water sources and actually encourages water-hogging lawns and golf courses.

IPR on the other hand, takes wastewater, filters it and leaves it extremely clean to be re-introduced into a water source. To learn more, I decided to tour the Orange County (OC) Groundwater Replenishment System and the North City Water Reclamation Plant.

The OC Groundwater Replenishment System has been operating for several years now. This facility has been a model not only for San Diego, but for other facilities worldwide. Here, water is put through a very simple filtration system that takes in wastewater, cleans it and it exposes it to ultraviolet rays to make sure all pollutants are removed. The water, clean as whistle, is then pumped into the Orange County groundwater basin. At the end of the tour, I was given the opportunity to taste the water. A little skeptical at first, I decided to taste it. The water was the best water I had ever tasted! It was so fresh and soft that I wished I had been given the opportunity to take some it home!

Anxious to see what San Diego was up to, I took a tour of the North City Water Reclamation Plant. San Diego is currently in its third month of its Advanced Water Purification Demonstration Project. The filtration process is the same as that of the OC facility, giving the same water quality results. San Diego is assessing the possibility of using IPR water to augment the San Vicente water reservoir.  

IPR works! This is not a case of toilet to tap or dirty water aimed only for low income communities. The water would be the same for everyone. IPR is a great way to replenish our water levels without having to import more water. Many question the use of wastewater, but the process is extremely clean and by re-introducing it into a groundwater basin or reservoir, it allows it to clean itself even more!

If you have doubts, don’t hesitate to tour these facilities. They’re open to the public and welcome public input. We cannot continue to claim that we do not have a water crisis. We must act to solve our water crisis and a great way to do so is to support IPR.

Stop the Flaming Gorge Pipeline!

It may seem strange for San Diego Coastkeeper to call a project happening almost 1000 miles away to your attention, but the Flaming Gorge Pipeline has a strong San Diego connection.  

The Pipeline is a water project that would divert at least 250,000 acre-feet (81 billion gallons) of water annually from the Green River and Flaming Gorge Reservoir in Wyoming, across the Continental Divide, and down the Front Range of Colorado, a total of between 550 and 580 miles. The Green River is the chief tributary of the Colorado River, where San Diego gets half of its water supply. Check out this map of the area and proposed pipeline. The pipeline, a hydropower project as well as a water transfer, would generate up to 1000 megawatts, and the water is intended for future population growth. (Originally the project was solely for water supply, but it is now primarily a hydropower project.)

One complicated detail is the amount of water that will be delivered. Aaron Million, the Colorado businessman proposing the project, intends to transfer at least 250,000 acre-feet. A study by the Bureau of Reclamation, however, found that the Flaming Gorge Reservoir, where most of the water is coming from, has only a 165,000 acre-foot surplus. The remaining 75,000 acre-feet is coming from the Green River above Flaming Gorge. This will drain an approximate 20-25% of the Green River’s flow annually, which has negative impacts on both the environment and the tourist economy. The Colorado River Water Conservation District is opposed to the project, due to concerns about how much water can sustainably be delivered. Million believes that there is plenty of water in the Colorado River Basin for the project, and says that if major environmental problems are found, the project should not go forward. Million also claims that the project will cost only $2.8 to $3.2 billion, while the State of Colorado finds a figure of $9 billion far more likely. The water could cost up to $30,000 an acre-foot, the most expensive water in Colorado history.

A coalition of nineteen conservation groups is opposed to both the project and a $150,000 grant currently under debate that would set up a task force to consider the pipeline. Million himself estimates that $5 million has been spent already on studies, and that $8 million to $12 million more could be needed to finish studying the project. The coalition hopes to avoid spending more money on a project that should not even be considered, due to a number of problems including environmental issues and negative impacts on the tourist industry.  

Whether we like it or not, San Diego will be affected by the pipeline. Since we get half of our water from the Colorado River, there is a potential for reduced water supplies or perhaps higher prices due to lower supply, if the pipeline goes through. The pipeline stands to drain all of the water that can be spared from Flaming Gorge, possibly more, which could lead to shortages throughout the Colorado River basin in dry years.

The coalition has a petition at that anyone can sign, regardless of where they live. The petition closes September 12, and the Colorado Water Conservation Board votes on whether to fund a study of the project on the 13th and 14th. Sign now to show your opposition to the Flaming Gorge Pipeline!

Where does San Diego’s water come from?

If you have lived in San Diego for any length of time, you have probably noticed that it doesn’t rain very often here.  Yet if you look around, you’ll find you’re surrounded by lawns and swimming pools.  Where does the water come from to support all of this?  The short answer – not here.  San Diego County is a dry one, where a few isolated areas, the wettest in the county, get up to 45 inches of rain per year.  The driest gets nine.  San Diego city, where Coastkeeper is located, gets between nine and twelve inches per year.  Compare that to Northern California, where the wettest areas get up to 125 inches annually and where 40 to 75 inches is not uncommon. See this map for a breakdown of the annual rainfall in San Diego County, and this one for the average annual rainfall in California.  


Image Credit San Diego County Water Authority, Sources of San Diego County’s Water Supply

San Diego’s limited amount of rainfall, in addition to other local sources, only accounts for about 20% of its water supply.  (Local supply includes surface water, or lakes and streams; groundwater; recycled water, also known as ‘purple pipe’; and conservation.)  The other 80% must be imported.

The Colorado River, source of half of San Diego County’s water, was first allocated in 1922 in the Colorado River Compact.  The Compact divides the usable flow of the Colorado River – 7.5 million acre-feet (an acre flooded a foot deep) – between the Upper Basin (Colorado, New Mexico, Utah, and Wyoming), and the Lower Basin (Arizona, California, and Nevada).  Each basin subsequently divided its portion among its member states, assigning each state a number of acre-feet for its entitlement.  This is important, because that assigned number for each state stays the same no matter how much water is actually in the river.  Problems have arisen since the original apportionment due to both simple squabbling over who should have the bigger slice of cake, and more problematically, because the cake isn’t actually as big as it was thought to be when it was apportioned.  The 7.5 million acre-foot “total” that can be taken without harm to the river was measured during a wet year, and so when the states use their allocated amount of water, they use more than the river can spare.

The State Water Project has its own set of problems as a water source.  The water ultimately comes from the Sacramento/San Joaquin River Delta.  The Delta is currently overdrawn, menacing the seven endangered and threatened fish species that call it home.  One in particular has served as the poster child for the recent Delta debates – the Delta smelt.  It’s a small fish, easily held in the palm of the hand, and its susceptibility to pollution makes it a good water quality indicator.  Concern for the species’ survival helped push through the Delta Plan, new legislation from November 2009 which puts conservation of the Delta on par with providing more reliable water supply to Southern California.  This has the effect of reducing the water transferred to Southern California – good for the fish, but inconvenient for the humans.

The humans have always had a bit of a problem with water supply in Southern California.  They have refused to recognize its limits, preferring instead to rely on massive water relocation projects to meet their needs.  This is not a sustainable path – there are very few other places we can take water from.  We need to start learning to conserve and live within our limits.   Visit for some ways to conserve.

Water Unwise: Answers to the burning questions

This is the third of a 5-part blog series examining the nature of our local water supply and how to increase the reliability of our supplies now and into the future.

Recently we posted a video of watering turf grass at Liberty Station. We asked you to see if you could spot whether there were any water unwise things in the video. I am sure you have been waiting with baited breath for the answer.

As I hinted in the last blog post, to get a sense of what is technically incorrect, we need a quick review of what our local ordinances say about irrigating.

  • First thing we need to know is that the San Diego City Council removed the Drought Level 2 status. Our City Council exercised some foresight last year and made a few of the drought level 2 restrictions permanent. Now, drought or no drought, there are just some things you cannot do, end of story.
  • Which brings us to the next important things you need to know – it is still illegal to water your lawn between 10 a.m. and 6 p.m. (June to October) and 10 a.m. and after 4 p.m. (November to May); and “City of San Diego water customers must prohibit excessive irrigation and must immediately correct leaks in their private water systems” (emphasis mine). The City’s regulations now state that customers “shall not allow water to leave their property due to drainage onto adjacent properties or public or private roadways or streets or gutters due to excessive irrigation and/or uncorrected leaks.”

Thus, according to the letter of the law, Liberty Station is within the bounds of legal limits in terms of when they water all that turf – the video was shot in May, at 9 AM. BUT, the video clearly shows excessive irrigation (as evidenced by the water flowing on the sidewalks, pooling around the sprinkler head and flowing into a drain).


Jill Witkowski

The video demonstrates a clear violation of the letter of the law.

But beyond that, there is a clear violation of the spirit of the law as well, which in my mind is meant to keep all San Diegans – whether they manage a small house or a large commercial development – living within our water means. Given our climate and troubled water supply, we should always be striving to make the best water use decisions possible. To their credit, Liberty Station is participating in a pilot Water Savings Performance Program. They have installed an automated irrigation system that determines the length of time and the days to irrigate based on weather, soil, microclimate and plant material. This is a good start but is clearly not sufficient.

But what is a historical site that is trying to pay tribute to its military roots supposed to do?

Well, there are many things Liberty Station could have done and still could do. As Morgan, one of our commentators pointed out “Turf is not water wise … period.” There are other native and drought tolerant ground covers that look similar to turf grass and would help maintain the look of old military training fields of yore.

While it is great that Liberty Station has installed a fancy water-saving irrigation system, they lose half the battle if they don’t check to make sure it is working properly:

  • sprinkler heads spraying water onto concrete should be addressed immediately;
  • lawns could easily be watered earlier in the morning (just around dawn is generally considered best);
  • water should be applied more slowly by switching to more efficient irrigation heads (thanks again to our commentator Morgan for that idea).

Of course, these kinds of changes cannot happen overnight. But with a thoughtful plan for improving water management on site, Liberty Station could identify opportunities over the coming years to change its water path. We believe that any place – not just Liberty Station – can and should craft plans of action that lays out a vision and tasks for achieving water sustainability.





Can you spot the water waste?

This is the second of a 5-part blog series examining the nature of our local water supply and how to increase the reliability of our supplies now and into the future.

Among the many things that make working at Coastkeeper great is the location of our offices. We come to work each day at Liberty Station – from our windows we can see a glimpse of San Diego Bay, the old navy channel, gardens and playing fields and historic buildings. But our buildings also stand amid a sea of turf grass. Personally, I prefer walking around gardens and pseudo-open space over walking through looming skyscrapers. But, turf grass means water – a lot of it.

At Coastkeeper, we like to think of ourselves as good water-Samaritans, so our staff is always on the watch for water waste. Recently, our intrepid Communications Director Jamie Ortiz, noticed clear signs of water waste right outside our front door at Liberty Station. Being the tech savvy person that she is, she documented it on video. I thought this might make for a fun water-wise quiz – How many water unwise things can you spot in this video? The video was taken on May 3, 2011 at 9 a.m.

Hint: you might need to check the City of San Diego’s current water use ordinances to find out what is technically not allowed.

Feel free to fill out your answers in a comment box or just remember your answers and check back in one week when we post the answers.

Survey Says…. We still need to conserve more water



Credit San Diego County Water Authority.  2011 Public Water Survey.

This is the first of a 5-part blog series examining the nature of our local water supply and how to increase the reliability of our supplies now and into the future.

On April 12th, the Board members of the Metropolitan Water District of Southern California (MWD) voted to end the 2009 decision to limit water deliveries to the Southern California agencies. What does a board vote by a L.A. public agency have to do with San Diegans you might ask? Well, a lot actually.  In 1946, the County Water Authority joined the MWD to get deliveries of imported water from the Colorado River.  In addition, all the water San Diego receives from Northern California through the State Water Project comes via the MWD. The MWD, as the largest individual source of supply, controls the spigot to most of the water in San Diego.

In response, the San Diego County Water Authority board voted yesterday to end the mandatory cutbacks. Effective today, the County Water Authority will restore full urban water deliveries to its 24 member retail water agencies. Each of these agencies now has the opportunity to maintain or lift its own restrictions. To some, this news will be greeted with joy – no more “drought alerts”; no more worrying about when to water your lawn. Just green lawns, long showers, happy times. To others, the short-sightedness of these decisions brings concern and consternation.

On the surface it seems sensible – the past year has brought plenty of rain and snow in California and major reservoirs are re-filling across the state. No more drought means no need for extreme emergency measures. Mayor Sanders has called for the City of San Diego to lift its restrictions because “emergency regulations should be reserved for emergencies”. But he is missing the point – very low water years are a regular part of Southern Californian life – not something unfortunate that just happens occasionally.

To its credit, the County Water Authority acknowledged that despite this vote “our state’s water supply system is still in crisis” and we still need to do our best to use water responsibly. Maybe as an effort to balance its decision to end the restrictions, the County Water Authority also pointed to results from their annual public survey of County residents to reassure the public that “most residents plan to continue their water-saving practices under a variety of conditions, including the end of mandatory water use restrictions”. Eighty three percent of all survey respondents agreed that they would continue to comply with the mandatory water restrictions if they were lifted whether or not they had reduced their usage in the past.
















Now that does sound reassuring. But public opinion polls often produce conflicting results and this one is no different. If you look at the results of the survey, you will find some results that cast doubt that voluntary conservation will continue. The survey also found that only 31% of respondents reduced their household water usage last year. A majority of respondents also said they would return to a higher usage if their families grew, if there was a hotter/drier year, or they moved to a larger home). To me, these results among others demonstrate that despite the success we had in conserving water since 2009, maintaining these conservation gains in the future will require concerted regulatory effort.

The most encouraging results in the survey, was that support for treating recycled water to potable standards is increasing (over-half of respondents found it acceptable), something Coastkeeper has been promoting for our region. And a majority of respondents also indicated support for maintaining mandatory restrictions.

So, I am putting out a call for my own informal, perhaps not statistically-robust survey. Fill out a comment field and tell me what you think – should your local water agency keep its water restrictions in place? What, if any, actions have you taken to reduce your water footprint? Will you keep doing them if your local supplier ends the restrictions? Better yet, tell your local water supplier what you think.


Free Rain Barrels for San Marcos Residents

Good news for San Marcos residents who want to do their part to solve our urban runoff program.  This Saturday, the City of San Marcos and Vallecitos Water District will be giving away rain barrels—free—at a workshop.  

The event will take place from 9 a.m. to noon Saturday at Vallecitos Water District’s offices at 201 Vallecitos de Oro in San Marcos.  Space is limited, so to register, call Torrey Webb at 760-744-0460, ext. 238.

rainwater_harvestingRain barrels can be a great way to tackle two important water issues:  water quality and water supply.  By capturing water, rain barrels reduce the amount of water running off our roof, across our lawns and into the storm drain.  This reduces the total amount of pollution that makes its way into our ocean and waterbodies.  And it also reduces the amount of total water in our creeks during storm events, which reduces hydromodification, which includes devastating erosion of our creeks and waterways.

Rain barrels also address a water supply issue.  By capturing water in rain barrels,  residents can “harvest” the captured water and use it to irrigate their lawn and garden—reducing the amount of water they would otherwise use to irrigate their yards.

The city and the water district planned the workshop as part of long-term requirement to reduce pollution to San Marcos Creek.  The city needs to reduce pollution—including bacteria, nitrogen and phosphorus—into the creek by 2021.

San Diego Coastkeeper has been involved in efforts with other stakeholders, including the City of San Marcos and Vallecitos Water District, to address pollution in Lake San Marcos, which was created by the damming of San Marcos Creek. To learn more about efforts to reduce pollution in Lake San Marcos and the Upper San Marcos Creek, click here.

Published in Urban Runoff

From Organic Farming to Drinking Water: Water Purification in San Diego

Our Tijuana River water quality tests from last week got me thinking about the safety of food grown at Suzie’s Farm, located in the Tijuana River Valley. I receive my Community Support Agriculture (CSA) box from Suzie’s Farm every Wednesday, and I wondered if the water quality of the Tijuana River put my organically certified grown food at risk.

So I asked.

Lucila, who owns the wonderfully titled job of Head Weed Puller, responded with this note:

Being a USDA certified organic farm we are concerned with water quality too. We use a well that is tested yearly and certified. The well has been found to be at a level consistent with 10,000 years ago; so it’s pretty deep. Our well water is then run through a reverse osmosis system, so the water with which we irrigate our fields is more pure than San Diego City water. We do not irrigate with water from the river.

Feel free to contact us with more questions or concerns regarding our water quality or any of our agricultural practices.

This means that Suzie’s Farm grows the food I serve for dinner with water so pure, it’s better than what comes out of my tap. Which begs the question, could this process be used to help with our currently endangered water supply?

At Coastkeeper, we advocate for a wasterwater purification process to help our region find reliable sources of water. The Point Loma Sewage Treatment Plant currently treats sewage and pumps it into to our ocean. Rather than dispose of that water, we want the city to run it through a similar reverse osmosis process used by Suzie’s Farm so that we can add the highly purified water to our drinking reservoir, and thus increase our water supply. It’s water so pure, it’s drinkable.

You can learn more about this process, called Indirect Potable Reuse, on our website. And I’d love to hear your thoughts on this potential water supply.