In a recent article I wrote that California's biggest danger to water reliability isn't the lack of dams or groundwater, it was the State's growth policy that's forces city's to build. In its drive to produce housing to meet a desktop analysis that says the state will grow to ~51 million people, the state uses a little known legislative law called RHNA that 'tells cities' throughout the state how many units they must provide for. The cities must then answer in response by identifying properties (and even re-zone to allow for higher densities) where developers can build those units if the properties become available on the market.
Recently a news article listed Nine California cities running out of water. Most of them are in the central valley where it is especially bad. To emphasis how disconnected the State's RHNA process to the water challenges that cities face, I've provided is a list of those nine cities along with the number of units each city's is allocated to provide for and a rough estimate1 on how much water will be needed to support those units should they be built out.
On one hand each of theses cities are confronted with a huge water deficit resulting in an unreliable water supply and on the other hand the State is pushing them to increase housing in places where its no longer practical. Literally RHNA is running cities out of water. The housing allocations are running up water demand to the point where cities have insufficient supplies.
Between the 2006/2013 and 2014/2021 RHNA allocations, the City of Los Angeles has had to identify properties that could be developed for 194,000 units.
In the most recent Water Board Water Conservation Report, LADWP has been revising population figures presumably to keep the Residential-GPCD level from getting out of control. They are now projecting monthly population growth and using each months figures to calculate residential water use. The screen shot from the report shows the city has projected that it has grown by 55,089 residents while the water supply has dropped.
RHNA forces cities to identify properties that are suitable for development for the number of units they are allocated for. Despite the 7 year long water deficit the city has been fighting, the increasing population numbers that the LADWP is providing is a result of the California's RHNA requirement. If a developer want to build on a property identified in the Housing Element (a RHNA requirement), the city can't say no.
Now that we find that the City of Los Angeles routinely props up its water portfolio using 'paper water' so where do we find it? We first find evidence of the city's reliance on paper water in the groundwater projections cited in each of the Urban Water Management Plans between 1985 and 2005.
The chart at the right plots the gap between the actual groundwater supply the city had access to and the anticipated supplies that each UWMP projected. The gap between the two is the paper water that would be used to as evidence that medium and high density projects going through the planning process would have sufficient water when in fact they didn’t.
The city routinely projected supplies that ranged from 103,000 AF to 155,000 AF during that period. Including a brief period between 1997 and 2000 of exceptionally high pumping, the actual amount of well water produced by the city was 33% below expectations. Far below the city's expectations and glossy presentations that suggested that growing groundwater supply would help the city meet its needs and allow its growth ambitions.
Despite the city's average of just 71,000 AF since 2001, the city's current 2010 water plan continues propping up it's paper water inventory citing that it should an average of 107,426 af/y in available groundwater supplies between the years 2020 and 2035.
Between 2000 and 2014 the city's groundwater supply would remain flat at 71,059 af/y which is far below any of the past UWMP projections that ranged from 103,000 af/y to as high as 152,000 af/y.
This gap between 'projected or anticipated supply' and 'actual supply' is an unfortunate characteristic of the city's water supply. It's a promise spanning 5 water plans and 25 years that was used to mischaracterize the city's supply to approve high density development.
The City's failure to meet groundwater projections stems primarily from the fact that it is just storage. The City of Los Angeles Stormwater Program reports that the city captures just 27,000 AF of water to recharge the underground storage. The reason for this can be found in Upper Los Angeles River Area Watermaster reports which state that "The continued growth of residential, commercial, and industrial developments has required that more water be imported to supplement the local groundwater supplies in ULARA over time. Imported supplies to ULARA are from the Los Angeles Aqueduct and from MWD".
Because of the extent of development in the valley, much of today's potential groundwater supply is simply channeled into storm drains and down the LA River. Secondly, ULARA reports that many of the San Fernando Valleys groundwater pumps have been taken out of service due to groundwater contamination.