BILL ANALYSIS �
SB 1259
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Date of Hearing: June 17, 2014
ASSEMBLY COMMITTEE ON WATER, PARKS AND WILDLIFE
Anthony Rendon, Chair
SB 1259 (Pavley) - As Amended: May 27, 2014
SENATE VOTE : 35-1
SUBJECT : Dam sedimentation studies
SUMMARY : Requires the Department of Water Resources (DWR) to
analyze the loss of storage capacity behind dams resulting from
sedimentation. Specifically, this bill :
1)Authorizes DWR to initiate investigations and gather data as
needed to study the loss of storage capacity behind dams
resulting from siltation and allows DWR to focus on reservoirs
with a high volume of sedimentation or a high rate of
sedimentation.
2)Requires DWR to complete an initial sedimentation study by
January 1, 2017, and further require that the study include an
evaluation of cost-effective strategies for sediment removal,
relative to the costs of alternative methods of flood
protection and water supply.
3)Requires that the results of any siltation study be reflected
in DWR's California Water Plan updates.
EXISTING LAW:
1)Authorizes DWR to supervise the construction, enlargement,
alteration, repair, maintenance, operation, and removal of
dams and reservoirs for the protection of life and property.
2)Authorizes DWR to initiate investigations and gather data as
needed to study the various features of the design and
construction of dams, reservoirs, and associated facilities.
3)Establishes, as the policy of the state, that the California
Water Plan guides the orderly and coordinated development,
management, and efficient utilization of the water resources
of the state and requires DWR to update the California Water
Plan every 5 years.
SB 1259
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4)Requires, as part of each California Water Plan update, that
DWR conduct a study to determine the amount of water needed to
meet the state's future needs and to recommend programs,
policies, and facilities to meet those needs.
FISCAL EFFECT : According to the Senate Appropriations
Committee analysis there would be cost pressures of
approximately $10 million from the General Fund to DWR to
conduct sedimentation studies of the reservoirs in the state.
However, amendments taken following the Appropriations Committee
provided DWR further discretion to limit the scope of the study
to reservoirs with a high volume of sedimentation in them or a
high sedimentation rate. As a result this estimate is likely
lower but by an unknown amount.
COMMENTS : In 2009, Water Resources Research published a paper
by J. Toby Minear and G. Matt Kondolf entitled "Estimating
reservoir sedimentation rates at large spatial and temporal
scales: A case study of California." Based on their modeling,
the authors estimated that statewide reservoirs have likely
filled with 2.1 billion cubic meters of sediment to date,
decreasing total reservoir capacity by 4.5%. The report also
stated that about 200 reservoirs have likely lost more than half
their initial capacity to sedimentation. The authors of the
study estimate that 2.1 billion cubic meters of sediment is
equivalent in volume to about 1.7 million acre-feet of water.
In many places in California that is enough water to serve 5
million families or more.
Supporting arguments : The author advises that studies show that
the state's reservoirs have lost a significant amount of storage
capacity due to siltation and that restoring that capacity could
greatly increase the State's ability to store water, potentially
by millions of acre-feet. However, the author adds, we don't
have sufficient information to know which reservoirs are most
impacted and which have the greatest potential for
cost-effective sediment removal. This bill addresses that
problem. Other supporters emphasize that sediment removal
should be considered part of a portfolio of water resources for
California and that removing and treating sediment would
significantly improve storage and flood management and could
create opportunities for watershed restoration.
SB 1259
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REGISTERED SUPPORT / OPPOSITION :
Support
Sierra Club California
Opposition
None on file.
Analysis Prepared by : Tina Cannon Leahy / W., P. & W. / (916)
319-2096