Tag: UWMP

Dissecting L.A’s Paper Water – Groundwater

Published / by dcoffin / Leave a Comment
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.
GWprojA
Groundwater supply is just 67% of UWMP projections.
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. GWToTotal Paper Water 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.

L.A.’s First Water Plans – The 1985 & 1990 UWMP

Published / by dcoffin / Leave a Comment
In 1983 the State of California passed the Urban Water Management Plan Act that required water suppliers to provide a water plan every five years. 1985UWMPCoverThe Urban Water Management Plan (UWMP) is rich in information as it identifies the agencies sources of water (aqueduct, groundwater, imported), amounts of water available from these sources, methods of conveyance, current and future water uses, projected demand, current and future conservation methods, demographics, population density and growth, housing mix, commercial/industrial/governmental demand, etc. The importance of the UWMP is that it is used as a guideline for making public decisions concerning water and is cited in planning documents, water supply assessments. But the UWMP can also be seriously misused when 'paper water' is inserted into the plans which provides a misleading assessment of the water supply or when city officials simply rubber stamp the findings without any sort of reassessment given current water supply availability. The City of L.A.'s UWMP's are both fascinating and disappointing in that they paint a picture of great expectations, a long term failure to meet demand and worse, a misleading assessment of the city's true water supply. What follows is a retrospective look back at previous UWMP's. What we find is a blueprint to a permanent water deficit. The 1985 UWMP - L.A.'s First Water Plan
Figure 1
The 1985 UWMP was the first state mandated water plan published by LADWP. This first time report was an honest and useful assessment of the city's water supply at the time. The plan assumed the city would receive a constant 470,000 Af/y supply through the Los Angeles aqueduct, 103,000 Af/y of groundwater and a small but growing reliance on MWD water between 1986 through 2010. From a planning perspective the most important part of the UWMP are the tables that show the projected water requirements at 5, 10, 15, and 20 increments for average years. The tables break down how much water the city assumes it will receive through the aqueduct, local groundwater, MWD, and recycled water. It's important that these projections meet the actual supply 5, 10, 15, and 20 years later because they are used in environmental impact reports and water supply assessments as guidelines for future development. If the actual supply doesn't meet the projections then we can assume we are creating a water supply deficit. (more…)
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