The City of
Because the City relies almost entirely on water from rainfall and water stored in the Loch Lomond Reservoir, the system is vulnerable to water shortages during severe drought conditions.
In normal and wet years, when rainfall and
runoff are normal to abundant, base flows in the coast and river
sources are restored by winter rains. Storage in Loch Lomond
Reservoir is typically replenished to full capacity with runoff from
the Newell Creek watershed and water diverted from the
The City experienced severe water supply deficiencies in both the 1976-77 and 1987-92 droughts. In 1977, the City imposed severe water rationing in response to a critical shortage of water. During the 1987-92 drought, a water supply emergency was declared and either usage restrictions or rationing was imposed each year for five consecutive years. The 1976-77 event has since been established as the most severe drought of record, and is used by the City as a benchmark for assessing system reliability. If a critical drought similar to 1976-77 occurred today, shortages would be in excess of 40 percent.
The City is currently updating information on water demands, supply reliability, water conservation measures, and water shortage contingency planning as part of the updates to the Urban Water Management Plan and the environmental review process for the proposed desalination project. This information will be incorporated into the Draft Environmental Impact Report (EIR) that is being developed for the proposed project. Water shortages related to drought conditions with updated demand projections will be included in this evaluation.