The Problem Owens Valley, a stretch of land in Inyo County California, contains landscapes that have been entirely transformed by environmental issues and changed by human agency. Around 1913 the Los Angeles reclamation project effectively diverted water from Owens Valley to the Los Angeles Aqueduct, feeding the city’s water supply. By 1926, the lower Owens River and Owens Lake were essentially depleted of water, leaving a vast exposed salt flat. Since then the Owens Lake region has become the largest source of particulate matter pollution in the United States. Dust blowing from the dry lakebed is the major contributor to violations of the federal particulate (dust) standard in the extreme southern Owens Valley.
“So how do you go from dealing with a public utility that has to be dragged kicking and screaming through decades of litigation just to get it to fix a public health disaster it inadvertently created to having that same utility embrace and manage an elaborate set of wildlife and bird habitats, complete with public access to invite people into this strange but beautiful place? You do it with data, you do it with heart, and you do it with years of dogged persistence.” – The Owens Lake Project
The Solution
In 1983 the state legislature passed a bill that authorized the Air Pollution Control District (APCD) to require the City of Los Angeles to provide reasonable mitigation of air quality impacts associated with its water gathering activities while at the same time protecting the City’s water rights from interference by the APCD. Both the City and the APCD supported this compromise solution.
In July of 1998 Los Angeles and the Air Pollution Control District entered into an historic Memorandum of Agreement (MOA) to mitigate the dust problem. The MOA delineated the dust producing areas on the lakebed that needed to be controlled, specified what measures must be used to control the dust, and specified a timetable for implementation of the control measures. The MOA called for phased implementation to permit the effectiveness of the control measures to be evaluated and modifications to be made as the control measures were being installed.
Phase 7a Dust Mitigation project: 7/11 Materials Inc. partnered with Barnard Construction to provide concrete and aggregates for Phase 7a. As this project wound to a close, LADWP was in its 15th year of dust mitigation to compensate for the draining of Owens Lake early in the 20th century. Phase 7a was a fast-track project with the continued goal of keeping dangerous dust from arising off the 108-square-mile lakebed that is prone to dust storms. Located roughly 200 miles northeast of Los Angeles at the foot of the Sierra Nevada mountains, Owens Lake is a remote, extremely hostile environment with varied, challenging soil conditions. Phase 7a included the installation of 24,000 sprinkler heads for shallow flooding and managing vegetation, using over 400 miles of pipe, 900,000 tons of gravel, 1 million tons of earth moved for berms, roads, and fill, 14 miles of power cable, 40 miles of berm roads, and used approximately 200 pieces of equipment. Three miles of walkways will also be built to provide public access with information signs on the project as well as local wildlife.
General Statistics and Accomplishments
90% of dust is now controlled and Owens Lake is no longer in the top 10 of PM10 emissions
45 miles of dust control is now in operation with the completion of phase 7a
Annual operations and maintenance costs: $25 million. The maintenance lowers environmental impact as well as provides jobs for local residents.
Dust control cost is now equivalent to two months per year of an average CA residential customer’s water bill.
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