Wednesday, August 20, 2014
YOLO COUNTY NEWS
99 CENTS

Bypass floodwaters close wildlife area

Floodwaters make a pattern in the Yolo Bypass Wildlife Area on Thursday afternoon, after the Fremont Weir was overtopped on Monday. The bypass, about three miles wide and 40 miles long, handles overflow from the Sacramento River. Sue Cockrell/Enterprise photo

By
From page A1 | December 28, 2012 |

The Yolo Bypass is filling with water due to the recent heavy rains, and the Yolo Bypass Wildlife Area is in the midst of a seasonal closure as a result.

The California Department of Fish and Game announced Monday that the Wildlife Area was closing due to “forecasted flooding until further notice.”

And Ted Thomas, information officer with the California Department of Water Resources, confirmed Thursday morning that water is flowing over the Fremont Weir from the Sacramento River into the Yolo Bypass, and had been for the past day or so.

The Fremont Weir, completed in 1924, is a two-mile-long structure on the south side of the Sacramento River, not far from the confluence of the Sacramento and Feather rivers, at a point about eight miles northeast of Woodland and about 15 miles northwest of Sacramento.

When the river rises to 33.5 feet, water flows over the Fremont Weir and into the Yolo Bypass, which is roughly three miles wide and about 40 miles long. The Yolo Bypass conveys the water southward into the Sacramento-San Joaquin Delta, and the water ultimately flows into the San Francisco Bay.

The California Department of Water Resources describes the Yolo Bypass as “a great ‘safety valve’ taking huge quantities of water out of the river channel and allowing it to flow slowly and safely out to the delta.” Otherwise, there would be a high risk of flooding in the lower parts of the Sacramento urban area, a common event in the late 1800s.

When flooded, the Yolo Bypass also provides a stopover point for migrating wildfowl, and an excellent environment for fish that swim up through the delta to lay their eggs. Recent studies have shown that the slower-moving, nutrient-rich water in the seasonally flooded Yolo Bypass helps young fish grow more quickly than they would in the faster-moving, channelized Sacramento River itself.

At full flood, the Yolo Bypass also conveys an enormous amount of water — more than the river itself.

“The levee and bypass system along the Sacramento River system handle many times the normal flow of the Sacramento River,” according to the Department of Water Resources. When filled to capacity, the bypass system “carries a maximum of 600,000 cubic feet per second (cfs), many times the normal flow of the Sacramento River. Only a sixth of that flow — 110,000 cfs — is carried by the river itself. Nearly 500,000 cfs is channeled into the Yolo Bypass.”

This includes water that flows over Fremont Weir, as well as water entering the Yolo Bypass from creeks and sloughs along the side of the bypass.

The seasonal flooding of the Yolo Bypass in wet winters creates a large and comparatively shallow body of water.

“In more than half of all water years (from Oct. 1 to Sept. 30), the Yolo Bypass is inundated,” according to the Department of Water Resources. “When completely flooded, the Yolo Bypass covers an area equal to about one-third the size of San Francisco and San Pablo Bays. Water depths range from 10 feet in a heavy year to around 6 feet in a normal year.”

Seasonal flooding in the Yolo Bypass can inundate the acreage for anywhere from a few days to a few months, depending on how hard it rains and snows over the watersheds of the Sacramento River, the Feather River and their tributaries, officials said.

The Yolo Bypass includes about 59,000 acres of land, of which roughly 17,700 acres is part of the Yolo Bypass Wildlife Area. The remainder of the land includes private duck clubs and agricultural land, including a substantial amount of acreage devoted to rice.

— Reach Jeff Hudson at jhudson@davisenterprise.net or 530-747-8055.

Comments

comments

  • Recent Posts

  • Enter your email address to subscribe to this newspaper and receive notifications of new articles by email.

  • .

    News

    Summer jobs: a scramble for spots, extra cash

    By Spencer Ault | From Page: A1 | Gallery

     
    Davis Arts Center gets a new look, thanks to Brooks

    By Special to The Enterprise | From Page: A1 | Gallery

     
    Report details the face of hunger in Yolo County

    By Anne Ternus-Bellamy | From Page: A1 | Gallery

    ‘Monsters University’ to be screened in Central Park

    By Enterprise staff | From Page: A3

     
    California regulators approve PG&E rate hike

    By The Associated Press | From Page: B3

    America’s ‘it’ school? Look west, Harvard

    By New York Times News Service | From Page: B3

     
    School board preps for new academic year

    By Jeff Hudson | From Page: A3

    The big moveout, on ‘Davisville’

    By Enterprise staff | From Page: A3

     
    Sunder campaign will be at Farmers Market

    By Enterprise staff | From Page: A3

    Classic car show slated in Woodland

    By Enterprise staff | From Page: A3

     
    Students can practice safe bike routes to junior highs

    By Special to The Enterprise | From Page: A3

    Public opinion sought about Nishi Gateway

    By Lily Holmes | From Page: A4

     
    Davis Art Garage honored; bench dedication set

    By Special to The Enterprise | From Page: A8 | Gallery

     
    Woodland historical award winners announced

    By Enterprise staff | From Page: A8

    .

    Forum

    Delta-friendly water bond is a win for all of California

    By Special to The Enterprise | From Page: A6

     
    Bravo! The road diet works

    By Rich Rifkin | From Page: A6

    Support water bond in November

    By Letters to the Editor | From Page: A6

     
    Relay for Life team says thanks

    By Letters to the Editor | From Page: A6

    Tom Meyer cartoon

    By Debbie Davis | From Page: A6

     
    .

    Sports

    Crisp’s big hit helps A’s

    By The Associated Press | From Page: B1 | Gallery

     
    Aggie QB Baty is back to pass … Touchdown, Tina! Tina?

    By Bruce Gallaudet | From Page: B1 | Gallery

    I’m not an ‘athlete’ but curling is hard

    By Evan Ream | From Page: B1

     
    Hard hoops schedule features defending national champ at UCD

    By Bruce Gallaudet | From Page: B1 | Gallery

    UCD roundup: Aggie gymnasts are awesome at academics

    By Enterprise staff | From Page: B2 | Gallery

     
    Sacramento scores early to snap skid

    By Enterprise staff | From Page: B8

    Unplayable? Cubs, rain hand Giants a loss

    By The Associated Press | From Page: B8

     
    .

    Features

    Food that travels well for cooking out

    By Julie Cross | From Page: A5 | Gallery

     
    .

    Arts

     
    Visit Crawfish and Catfish Festival in Woodland

    By Enterprise staff | From Page: A7

    Artists invited to paint at Yolo Bypass Wildlife Area

    By Special to The Enterprise | From Page: A7 | Gallery

     
    Goldberg, Milstein to play at Village Homes

    By Enterprise staff | From Page: A7 | Gallery

    The voice on the CD comes alive at Music Together concert

    By Enterprise staff | From Page: A7

     
    Crowd funding campaign offers support for Art Theater of Davis

    By Special to The Enterprise | From Page: A7

     
    .

    Business

    .

    Obituaries

    Railroad museum will host Aberbach memorial

    By Enterprise staff | From Page: A4

     
    .

    Comics

    Comics: Wednesday, August 20, 2014

    By Creator | From Page: B6