By Don Greene
Note: This is a two-part series that Alianza North County will run to discuss the serious conditions of our region’s water supply and how our municipalities are dealing with the crisis. In the first part we look at the levels of supply and their sources. In the second part, we will look at waste water management and how we can turn that into a sustainable source of water for the future.
By now you’ve heard the word used to describe our current water availability situation in the State. For the past 4 years the level of snow pack in the Sierras – the main source of drinking water for the state, both Northern California and Southern California – has been at al-time lows. This year, instead of having the necessary five feet of snowpack in the Sierras, authorities found barely a foot in some locations.
This prompted Governor Brown to sign an executive order requiring water districts throughout the state to reduce water consumption by 25 percent. This is on top of the demands of the Stage 2 water restrictions that are already in place.
Along the 78 corridor, there are five water districts that provide water to the residents: City of Escondido, Vista Irrigation District, Vallecitos Water District, Carlsbad Municipal Water District and City of Oceanside. These districts are responsible for reducing consumption by the 25 percent mandated by the Governor while continuing to provide water to the residents they serve. This can be tricky.
We should look to the availability from our sources to understand how it is that we need to move forward.
According to information provided by the San Diego County Water Authority (SDCWA), roughly 80 % of all the water used by residents in San Diego County is imported from other sources. The main source is the California Aqueduct which runs from the Northern California area, through the Bay Delta, and down to San Diego County. We also source our water from the Imperial Valley and the Colorado River. Combined with the local sourcing availability of each water district, this is where our water comes from.
When the availability is as low as it is at the source, it means that we at the end of the line are left to handle the trickle that comes out of the pipe. As of March 31, 41 percent of the State is in what is categorized as “exceptional drought”. The snowpack in the Sierras which provides water to the system through run off throughout the year is at five percent of normal levels. As of April 1st the Sierras should have had approximately 30 inches of water content but only had about three inches.
Lake Oroville in Northern California – one of the largest reservoirs for our water – has a capacity of 3.5 million acre feet of water. Currently, as of April 6th, the lake is at 1.7 million acre feet; 51 percent of its capacity. That shows an increase in water over last year’s low of 25% of capacity, but we’re still not out of danger.
There are other considerations at play along with the general lack of availability which effects our water supply. The California Aqueduct is regulated heavily by state and federal agencies, such as the EPA. The aqueduct flows through the Bay Delta which is home to the Delta Smelt, a species of fish which is on the endangered species list. The presence of the fish in the bay and the aqueduct means that flow is regulated heavily to reduce the loss of the fish in the pumping equipment.
What do we do when faced with the need to conserve water and increase the sourcing of available inventory?
The good news is that water consumption is down, even in the face of increased demand. At the height of water use, the San Diego region used about 700,000 acre feet of water in 2007. For reference, an acre foot of water is approximately 325,851 gallons and is enough water to service two single family homes of four people for one year. In 2014, we saw an actual 20% drop in potable (clean) water use.
According to number provided by SDCWA, in 1990 the county used 641,000 acre feet of water with a population of 2.4 million. In 2014, there was a use of 566,000 acre feet of water with a population of 3.1 million. This is a good trend. What is not so good news is the cost of imported water. In 1990, the cost of an acre foot of water (in 2014 dollars) was $500; in 2014 that same acre foot of water costs $1303.
What then can be done? We need to begin to find new sources of water if we want to slow the rise of costs involved with imported water. Our region is beginning to do that. In 1991, the county used a total of 578,000 acre feet of water from two sources: 95% came from imported water through the California Aqueduct, 5% came from local water sources. In 2014, we have realized a bigger diversification of our water sources. The county used a total of 667,000 acre feet of water and only 49% of that water came from the Aqueduct; 27% came from the Colorado River, 11% has been saved through conservation measures, 4% came from recycled water usage, 9% from local sources. We are on track to see a reduction to 30% imported water from the Aqueduct by 2020.
Our local municipal water districts are doing what they can to help reduce the use/need for imported water. Escondido is expanding its purple pipe (recycled water) availability to the eastern portion of the city and providing a sustainable source for agriculture and city-owned properties. Oceanside is also increasing its purple pipe system to provide water to heavy water users (parks, golf courses, etc.) and reduce the need for potable water. Oceanside is also expanding its desalination plant to provide more water from the large source of water (the Pacific Ocean) to its west.
In Carlsbad, the Poseidon Desalination Plant is expected to come online at the end of this year and will be generating 56,000 acre feet of water per year. Of course, with this new technology comes increased costs and we will probably expect to see an increase in our costs. Hopefully, we will be able to mitigate these new costs with reductions in need from other areas.
Other measures are on the horizon. What has been called “toilet to tap”, both direct and indirect potable reuse offer another option for us to develop a sustainable source for water. These systems would allow for cleaned waste water (“toilet”) to be added to our potable water supply (“tap”) and help augment our supplies and lessen our dependency on imported water. The more feasible of the two is the indirect approach which would pump cleaned and treated water into our water basins to mix with existing supplies. Often times, this water is cleaner than the water being stored and would actually help increase the purity of the water in the reservoirs.
Whatever the chosen method, we must begin to think along the lines of conservation and sustainability when it comes to our water supply. Old ideas and attitudes will not be enough to help turn our current situation around; fresh ideas and approaches are needed to address the long-term needs of our region’s water dependence.