Oroville Dam is the centerpiece and largest water storage
facility of the State Water Project. Located about 70 miles north
of Sacramento at the Feather River confluence, Oroville Dam
creates a reservoir that can hold 3.5 million acre-feet of water.
Features such as a fish barrier dam and pool at Oroville Dam made
the SWP one of the first major water projects built with
environmental protections as a major consideration.
Besides storing water, the dam also protects downstream residents
from the floodprone Feather River—the main feeder of the SWP— and
provides major water recreation facilities such as boating,
fishing and camping.
California’s latest atmospheric rivers are sending rainfall
higher into the mountains and onto the state’s crucial
snowpack. The rain alone is a problem for low-lying areas
already dealing with destructive flooding, but the prospect of
rain on the deep mountain snow has triggered widespread flood
warnings. When rain falls on snow, it creates complex flood
risks that are hard to forecast. Those risks are also rising
with climate change. For much of the United States, storms with
heavy rainfall can coincide with seasonal snow cover. When that
happens, the resulting runoff of water can be much greater than
what is produced from rain or snowmelt alone. The combination
has resulted in some of the nation’s most destructive and
costly floods, including the 1996 Midwest floods and the 2017
flood that damaged California’s Oroville Dam. -Written by Keith Musselman, an assistant professor in
geography, mountain hydrology and climate change at the
University of Colorado Boulder.
In another sign that the drought is ending across much of
California, state water officials opened the floodgates at
Oroville Dam on Friday to let water out of the state’s
second-largest reservoir to reduce the risk of flooding to
downstream communities. … At noon, water began
cascading down the huge concrete spillway for the first time in
four years. On Friday, Oroville reservoir was 75% full —
or 115% of its historical average for early March. It has risen
180 feet since Dec. 1, and continued to expand steadily with
millions of gallons of water pouring in from recent storms.
With back-to-back storms to hit California in the coming days,
state officials are scrambling to make strategic releases from
key reservoirs in hopes of preventing a repeat of the flooding
that killed nearly two dozen people in January. At least 10
rivers are forecast to overflow from the incoming “Pineapple
Express” storm, which is expected to drop warm, heavy,
snow-melting rain as it moves from the Central Coast toward the
southern Sierra beginning Thursday night into Saturday. Among
them are rivers that flooded at the start of the year, when
nine atmospheric river storms pummeled the state. The waterways
include the Cosumnes River near Sacramento, where more than a
dozen levee breaches sent floodwaters onto roadways and
low-lying areas, trapping drivers and contributing to at least
three deaths along Highway 99.
As still more storms dumped new snow onto California’s
burgeoning snowpack, water managers, farmers and
environmentalists gathered in Sacramento last week to discuss
long-term challenges to secure a more certain water future. The
fresh snowfall contrasted with challenging water realities
discussed at the 61st California Irrigation Institute Annual
Conference. With a theme of “One Water: Partnering for
Solutions,” the event focused on addressing impacts of climate
change, including warming conditions and frequent droughts that
severely diminish the snowpack and state water supplies. The
gathering emphasized solutions that some speakers said could be
aided through partnerships among different water interests.
Over the past 10 years, California has seen two of the most
severe droughts in a millennium separated by two of the wettest
years on record. This erratic weather, volatile even by
California standards, shattered heat records, killed millions
of trees, fueled explosive wildfires and caused significant
flooding. As California’s changing climate pushes us deeper
into uncharted climate waters, past records are becoming a less
reliable tool for predicting current and future weather
patterns. That’s why Gov. Gavin Newsom’s recent decision to
delay the release of 700,000 acre-feet of water, enough to
supply nearly 7 million people for a year, from state
reservoirs into the Sacramento-San Joaquin-River Delta was the
right call. Snowpack from early storms can be lost to dry, hot
weather later this spring. -Written by Jim Wunderman, president and CEO of
the Bay Area Council.
The winter of 2023 isn’t finished yet. Not by a long
shot. An atmospheric river storm is likely to hit Northern
California late Thursday into Friday, meteorologists and
climate scientists said Monday, bringing high chances of heavy
rain in the Bay Area, 1 to 3 feet of new snow at higher
elevations in the Sierra, and an increased risk of flooding as
the warm rain hits the state’s massive snowpack. Details
about the storm, a classic “pineapple express” event barreling
in more than 2,000 miles from Hawaii, are still not certain.
… [Forecasters] said that the latest storm by itself won’t
likely be enough to cause major melting of the immense Sierra
snowpack — which on Monday was 192% of its historic average,
the most snow in 30 years — because the deep snow can absorb a
fair amount of rain.
Tremendous rains and snowfall since late last year have freed
half of California from drought, but low groundwater levels
remain a persistent problem, U.S. Drought Monitor data showed
Thursday. The latest survey found that moderate
or severe drought covers about 49% of the state, nearly 17% of
the state is free of drought or a condition described as
abnormally dry. The remainder is still abnormally
dry. “Clearly the amount of water that’s fallen this year
has greatly alleviated the drought,” said Daniel Swain, a
climate scientist at the University of California, Los Angeles.
“It has not ended the drought completely but we’re in a very
different place than we were a year ago.” California’s
latest drought began in 2020 and no relief appeared in sight
heading into this winter.
After another week of severe winter weather, levels in
California’s recovering water reservoirs have continued to
rise, signaling good news for the state’s summer water
supplies. This follows weeks of considerable rain and snowfall
in California since the start of 2023. … At the
beginning of this water year, which started on October 1, 2022,
the state’s largest water reservoir, Lake Shasta, was
a third full, at 33 percent. It was at 60 percent as of
March 1 and rising, according to the Bureau of Reclamation.
That puts it at 84 percent of where it would usually be usually
at this time of year.
After three of the driest years in California history, recent
storms brought some of the wettest and snowiest weeks on record
to parts of the state. Snowpack accumulated during winter is
vital to the state’s water system because the natural form of
water storage melts during the spring and fills reservoirs that
can then distribute water downstream where needed. The
Sierra Nevada snowpack supplies about 30% of California’s water
needs when it melts. How fast that happens can greatly impact
the state’s water supply system.
As January’s drenching storms have given way to an unseasonably
dry February, Gov. Gavin Newsom is seeking to waive
environmental rules in the Sacramento-San Joaquin River Delta
in an effort to store more water in reservoirs — a move that is
drawing heated criticism from environmental advocates who say
the action will imperil struggling fish populations. …The
agencies are requesting an easing of requirements that would
otherwise mandate larger flows through the estuary. The aim is
to hold back more water in Lake Oroville while also continuing
to pump water to reservoirs south of the delta that supply
farmlands as well as Southern California cities that are
dealing with the ongoing shortage of supplies from the
shrinking Colorado River.
Weeks after powerful storms dumped 32 trillion gallons of rain
and snow on California, state officials and environmental
groups in the drought-ravaged state are grappling with what to
do with all of that water. State rules say when it rains and
snows a lot in California, much of that water must stay in the
rivers to act as a conveyer belt to carry tens of thousands of
endangered baby salmon into the Pacific Ocean. But this week,
California Gov. Gavin Newsom asked state regulators to
temporarily change those rules. He says the drought has been so
severe it would be foolish to let all of that water flow into
the ocean and that there’s plenty of water for the state to
take more than the rules allow while still protecting
threatened fish species.
Facing an onslaught of criticism that water was “wasted” during
January storms, Gov. Gavin Newsom on Monday suspended
environmental laws to give the go-ahead to state officials to
hold more water in reservoirs. The governor’s executive order
authorized the State Water Resources Control Board to “consider
modifying” state requirements that dictate how much water in
the Sacramento-San Joaquin Delta is allowed to flow into San
Francisco Bay. In January, after floodwaters surged into
the bay, farm groups, Central Valley legislators and urban
water providers complained that people and farms were being
short-changed to protect fish. … Environmental activists say
Newsom’s order is another sign that California is shifting
priorities in how it manages water supply for humans and
ecosystems.
California Gov. Gavin Newsom (D) signed an executive order on
Monday to safeguard his state’s water supplies from the effects
of extreme weather. The order will help expand
California’s capacity to capture storm runoff during
wet years by accelerating groundwater recharge projects,
according to the governor’s office. While a string of
storms earlier this winter resulted in California’s wettest
three weeks on record, the Golden State is already experiencing
an unseasonably dry February, according to Newsom’s
order…. In addition, the order directs state agencies to
provide recommendations on California’s drought response by the
end of April — including provisions that may no longer be
necessary.
In the wake of the deluge of rain that battered California at
the start of the year, many of the state’s most important
reservoirs and lakes have seen water levels rise. The increase
in water levels between last fall and now at two key California
reservoirs—Lake Oroville and Lake Shasta—can be seen clearly in
photographs taken from space by NASA’s Operational Land Imager
(OLI) on the Landsat 8 satellite and by the OLI-2 sensor on
Landsat 9. … As of January 29, 2023, when the most
recent picture was taken, Lake Shasta’s water levels stood
at 986.93 feet above sea level, according to the California
Department of Water Resources, amounting to around 56 percent
of its capacity, and 87 percent of the average water levels for
this time of year. On November 18, when the first picture was
taken, the lake’s water levels were measured at 917.95 feet
above sea level, around 31 percent of the lake’s capacity.
The first week of February brought only modest amounts of rain
and snow but despite that, California’s snowpack and many of
the state’s largest reservoirs are in good shape. According to
data tracked by California’s Department of Water Resources, the
statewide snowpack is at 135% of the average peak. Typically
the snowpack peaks in late March to early April. … As of
midday Thursday, Lake Shasta is at 58% of capacity, which is
86% of the average for this date. Lake Oroville is at 67% of
capacity. That is 113% of the average for today’s date. Shasta
and Oroville are the two largest surface water storage
facilities in the state. Water storage will gradually increase
at both sites in the coming weeks and months as the Sierra
snowpack melts off.
This tour explored the Sacramento River and its tributaries
through a scenic landscape while learning about the issues
associated with a key source for the state’s water supply.
All together, the river and its tributaries supply 35 percent of
California’s water and feed into two major projects: the State
Water Project and the federal Central Valley Project.
Water Education Foundation
2151 River Plaza Drive, Suite 205
Sacramento, CA 95833
Land and waterway managers labored
hard over the course of a century to control California’s unruly
rivers by building dams and levees to slow and contain their
water. Now, farmers, environmentalists and agencies are undoing
some of that work as part of an accelerating campaign to restore
the state’s major floodplains.
This tour guided participants on a virtual exploration of the Sacramento River and its tributaries and learn about the issues associated with a key source for the state’s water supply.
All together, the river and its tributaries supply 35 percent of California’s water and feed into two major projects: the State Water Project and the federal Central Valley Project.
The deadliest and most destructive
wildfire in California history had a severe impact on the water
system in the town of Paradise. Participants on our Oct. 2-4
Northern California
Tour will hear from Kevin Phillips, general manager of
Paradise Irrigation District, on the scope of the damages, the
obstacles to recovery and the future of the water district.
The Camp Fire destroyed 90 percent of the structures in Paradise,
and 90 percent of the irrigation district’s ratepayer base. The
fire did not destroy the irrigation district’s water storage or
treatment facilities, but it did melt plastic pipes, releasing
contaminants into parts of the system and prompting do-not-drink
advisories to water customers.
This tour explored the Sacramento River and its tributaries
through a scenic landscape as participants learned about the
issues associated with a key source for the state’s water supply.
All together, the river and its tributaries supply 35 percent of
California’s water and feed into two major projects: the State
Water Project and the federal Central Valley Project. Tour
participants got an on-site update of Oroville Dam spillway
repairs.
This tour explored the Sacramento River and its tributaries
through a scenic landscape as participants learned about the
issues associated with a key source for the state’s water supply.
All together, the river and its tributaries supply 35 percent of
California’s water and feed into two major projects: the State
Water Project and the federal Central Valley Project. Tour
participants got an on-site update of repair efforts on the
Oroville Dam spillway.
In 2017, it is likely that no other water story grabbed as many
headlines in California and across the country as the flood
incident at Oroville Dam, the centerpiece of the State Water Project and
its largest water storage facility.
On our upcoming Northern California
Tour, we will spend time at the Oroville Dam visitor’s
center and meet with California Department of Water Resources
staff. You’ll see drone footage from February’s flood
incident, learn the engineering background on what led to it, and
hear about plans to stabilize the spillway before the next winter
storms and to finalize repairs by 2018.
One of the wettest years in California history that ended a
record five-year drought has rejuvenated the call for new storage
to be built above and below ground.
In a state that depends on large surface water reservoirs to help
store water before moving it hundreds of miles to where it is
used, a wet year after a long drought has some people yearning
for a place to sock away some of those flood flows for when they
are needed.
California Natural Resources Agency Secretary John Laird said
Tuesday that the February crisis with the broken spillway at
Oroville Dam offers an “important opportunity” to assess the
safety of the more than 1,400 dams in the state.
“We really want to use the focus on this to look at the issue of
dam safety in California,” he said during a hearing of the Senate
Natural Resources and Water Committee. “We have the best
inspection program of the 50 states but it is clear we can do
better.”
Work crews repairing Oroville Dam’s damaged emergency spillway
are dumping 1,200 tons of rock each hour and using shotcrete to
stabilize the hillside slope, an official with the Department of
Water Resources told the California Water Commission today.
The pace of work is “round the clock,” said Kasey Schimke,
assistant director of DWR’s legislative affairs office.
This 25-minute documentary-style DVD, developed in partnership
with the California Department of Water Resources, provides an
excellent overview of climate change and how it is already
affecting California. The DVD also explains what scientists
anticipate in the future related to sea level rise and
precipitation/runoff changes and explores the efforts that are
underway to plan and adapt to climate.
Water as a renewable resource is depicted in this 18×24 inch
poster. Water is renewed again and again by the natural
hydrologic cycle where water evaporates, transpires from plants,
rises to form clouds, and returns to the earth as precipitation.
Excellent for elementary school classroom use.
The 24-page Layperson’s Guide to California Water provides an
excellent overview of the history of water development and use in
California. It includes sections on flood management; the state,
federal and Colorado River delivery systems; Delta issues; water
rights; environmental issues; water quality; and options for
stretching the water supply such as water marketing and
conjunctive use. New in this 10th edition of the guide is a
section on the human need for water.
A new look for our most popular product! And it’s the perfect
gift for the water wonk in your life.
Our 24×36 inch California Water Map is widely known for being the
definitive poster that shows the integral role water plays in the
state. On this updated version, it is easier to see California’s
natural waterways and man-made reservoirs and aqueducts
– including federally, state and locally funded
projects – the wild and scenic rivers system, and
natural lakes. The map features beautiful photos of
California’s natural environment, rivers, water projects,
wildlife, and urban and agricultural uses and the
text focuses on key issues: water supply, water use, water
projects, the Delta, wild and scenic rivers and the Colorado
River.
Oroville Dam is the centerpiece of
the State Water
Project (SWP) and its largest water storage facility.
Located about 70 miles north of Sacramento at the confluence of
the three forks of the Feather River, Oroville Dam is an
earthfill dam (consisting of an impervious core surrounded by
sands, gravels and rockfill materials) that creates a
reservoir that can hold 3.5 million acre-feet of water.
This printed copy of Western Water examines California’s drought
– its impact on water users in the urban and agricultural sector
and the steps being taken to prepare for another dry year should
it arrive.
