Introduction
Main San Gabriel Basin Watermaster is the agency charged with
administering adjudicated water rights and managing groundwater
resources within the watershed and groundwater basin known as the
Main San Gabriel Basin.
Mission Statement
"The Main San Gabriel Basin Watermaster, a nine-person board appointed
by the Los Angeles County Superior Court, administers and enforces
the provisions of the Judgment which established
water rights and the responsibility for efficient management of the
quantity and quality of the Basin's ground water."
History
Watermaster was created in 1973 by the California Superior Court of
Los Angeles County to administer the Basin's adjudicated water
rights and to provide a basin-wide governing body for management
of water resources.
Background
Beginning in the 1940s, the San Gabriel Valley experienced a period
of rapid urbanization, which led to an increased demand for water
drawn from the Main San Gabriel Basin. The ensuing rise in water
consumption--along with an extended period of drought--had by the
1950s put the Basin into a state of overdraft, where water production
from the Basin exceeded the amount that could be replaced.
As a result of the decrease in available water supply, parties
downstream of the Basin became especially concerned. These downstream
water users rely on the Main San Gabriel Basin for a large portion of
their natural water supply, as much of it comes from the Basin by
way of outflow through Whittier Narrows. Legal action was
initiated on behalf of the downstream users, resulting in a court decision
which requires the Upper Area (Main San Gabriel Basin) users to
guarantee a source of water to the Lower Area or downstream users.
For several years the Upper San Gabriel Valley Municipal Water
District (Upper District) administered and took responsibility for
the Upper Area's obligations to the Lower Area. The Upper District
could not, however, assert control over all producers in the Basin
because the district boundaries do not encompass the entire Basin.
In 1968, at the request of producers, the Upper District filed a
complaint that would adjudicate water rights in the Basin and would
bring all Basin producers under control of one governing body.
The final result was the entry of the Main San Gabriel Basin
Judgment in 1973.
The Judgment
In order to bring about an adjudication of water rights in the Main
San Gabriel Basin, a complaint was filed in the Superior Court of
the State of California (Case #924128, Upper San Gabriel Valley
Municipal Water District, Plaintiff, vs. City of Alhambra, et al.,
Defendants). The original complaint was filed on January 2, 1968,
but was amended on August 14, 1970 to embrace the additional issue of surface
water diversion rights.
On January 4, 1973, after extensive negotiations, a stipulated
Judgment in this case was entered.
The Judgment defined the water rights of 190 original parties to the
legal action. It created a new governing body (the Main San Gabriel
Basin Watermaster), and described a program for management of water
in the Basin. Since the Judgment was originally entered, there
have been subsequent amendments to it that extend and clarify
Watermaster's role.
(The Main San Gabriel Basin is one of several adjudicated groundwater
basins in California. The Association of Ground Water Agencies
maintains a list
of all the adjudicated basins and their respective Watermasters).
Responsibilities and Functions
Watermaster's primary responsibilities include the following:
- Manage and control the withdrawal and replenishment of water
supplies in the Basin.
- Determine annually the Operating Safe Yield (the amount of
groundwater that can safely be extracted) for the succeeding fiscal
year, and notify the pumpers of their shares thereof.
- Acquire and spread replacement water as needed.
- Coordinate local involvement in efforts to preserve and restore
the quality of groundwater in the Basin.
- Assist and encourage regulatory agencies to enforce water
quality regulations affecting the Basin.
- Collect production, water quality, and other relevant data from
producers.
- Prepare an annual report of Watermaster activities, including
financial activities, and summary reports of pumping and diversion.
Watermaster operates under a formal set of Rules and Regulations, which
spell out the procedures by which Watermaster-controlled actions
are to be carried out. Under the Rules and Regulations, water
producers in the Basin must obtain Watermaster approval
for activities such as:
- Constructing or modifying a well.
- Constructing a groundwater treatment plant.
- Increasing groundwater extraction.
- Spreading water in the Basin.
- Spreading and storing supplemental water under a cyclic
storage agreement.
In order to fund its operation, Watermaster is authorized to levy and
collect assessments from the producers based upon their amounts of
production during the preceding fiscal year. These assessments
are applied primarily to the purchase of replacement water and to
administrative costs.
Area of Jurisdiction
Watermaster's area of jurisdiction is known as the relevant
watershed, which overlies a portion of the upper San Gabriel River
watershed. It is defined in the Judgment
as the watershed area within which water rights are adjudicated.
You may view a map of the
relevant watershed boundary. A written legal
description of the relevant watershed boundary is also available.
