A globally important bird area at the Great Salt Lake would be impacted by development of water resources provided by the Bear River. Plans call for water diversions that would reduce the flow of freshwater into habitats essential for a large variety and number of waterbirds.
River flows currently nourish about 400,000 acres of diverse wetland habitats at the river's delta at the Great Salt Lake.
The largest freshwater component of the Great Salt Lake ecosystem is at Bear River Migratory Bird Refuge, a tract of 74,000 acres established in 1928 as a federal reserve at the delta where the river enters the Great Salt Lake.
Counts by refuge staff in recent months document the extent of birds using refuge wetlands:
- • 25 Oct - 105,000 waterfowl including 480 Tundra Swan.
- • 18 Oct - 63,000 waterfowl including nearly 16,000 Northern Pintail.
- • 2 Oct - 67,000 waterbirds, with nearly 15,000 Ruddy Duck.
- • 31 Aug - 17,591 American Avocet.
- • 9 Aug - 57,639 American Avocet, 29,274 American Coot, 32374 Black-necked Stilt, 20,174 Dowitcher, 14,280 Marbled Godwit, and 46,141 White-faced Ibis; plus a multitude of waterfowl.
- • 19 Jul - record count of 369 red-necked phalarope; also 23,488 White-faced Ibis, 23,985 American Avocet and numerous other shorebirds.
- • 18 Oct - 63,000 waterfowl including nearly 16,000 Northern Pintail.
The value of refuge habitats for wild birds has meant its designation as an Important Birding Area by the National Audubon Society.
"Bear River Bay provides habitat for a large number of the world's total population of specific bird species including: White-faced Ibis, Marbled Godwit, American White Pelican, Tundra Swan, American Avocet, Wilson's Phalarope, California Gull, Cinnamon Teal, Western Sandpiper, Long-billed Dowitcher, Gadwall, Black-necked Stilt, Green-winged Teal, Western Grebe, Forster's Tern, Franklin's Gull, Northern Pintail, Northern Shoveler, and Redhead," according to the important bird area summary prepared by the society.
Other details indicate the value of the refuge and adjacent Great Salt Lake for migratory birds, according to the refuge website:
- "breeding colonies of white-faced ibis contain as many as 18,000 birds.
- "Up to 10,000 American avocets breed annually.
- "One of North America's three largest American white pelican breeding colonies, containing in excess of 50,000 birds, is found on Gunnison Island in Great Salt Lake.
- "The Great Salt Lake boasts the largest fall staging concentration of Wilson's phalaropes in the world, at approximately 500,000 birds. Red-necked phalaropes number nearly 100,000.
- "The Great Salt Lake area hosts greater than 50 percent of the continental breeding population of snowy plovers.
- "The Great Salt Lake area hosts 26 percent of the global population of marbled godwits during migration.
- "Bear River Refuge may attract over 65,000 black-necked stilts in the fall, more than anywhere else in the country."
"An environmental analysis reveals Bear River development would reduce the average annual outflow of the Bear by 18 percent," according to information provided by the Utah Rivers Council website. "In a low water year, the diversions would take as much as 70 percent of the river's flow. They will further degrade the already impaired waters of the Bear River, and drastically change the levels, water temperature, and salinity of the Great Salt Lake."
The "expected water level reduction in the Bear River Bay area would be approximately 6 to 12 inches," said Steve Hicks, manager of the Bear River Migratory Bird Refuge. "Due to the shallow nature of the Bear River Bay area, I would expect that water level drop to dry up thousands of acres of lake. The Bear River Bay is heavily used by shorebirds and waterfowl. Reducing the wet area available would force these bird populations into the remaining wet areas such as Bear River Refuge, and the Bear River Club marshes. Living space would be at a premium for the birds. In concentration, birds become stressed and disease outbreaks become more common. Existing food resources would also be more heavily utilized. It is quite probable that bird populations would respond downward."
Bear River basin (Map courtesy of the Utah Division of Water Resources, Bear River Development Report, August 2005). |
From its source in the Uinta Mountains, the river's watershed is within Wyoming, Idaho and Utah, and the Bear River flows nearly 500 miles until it empties into the Great Salt Lake at Bear River Bay, southwest of Brigham City, Utah River.
The average annual flow of the Bear River into the Great Salt Lake is about 1.2 million acre-feet, according to figures in the Division of Water Resources report. An estimated 250,000 acre-feet of Bear River water would be developed.
In 1999, the Bear River was listed as one of the ten most endangered rivers in North America by the national organization, American Rivers. The threats given were sprawl at Salt Lake City (an hours drive south from the Bear River refuge, water withdrawals and a proposed dam. Population growth is an additional threat, causing an increased demand for fresh water in the arid region.
The water available from Bear River runoff is already reduced in some years due to dryer conditions in the region that result in a reduced inflow of fresh water at the refuge.
"The water supply forecast for 2007 is for 'much below average' runoff in the Bear River basin which means less than 70% of normal" flows, according to the refuge's 2007 habitat management plan.
In 2006, the snow pack was above average. Previously five straight years of drought impacted flows, according to a report in the Deseret News.
The water in the Bear River is a target for water development.
The Bear River project is the result of passage of the Bear River Development Act in 1991 by the Utah legislature. The proposed project includes storage reservoirs, diversions and associated transportation facilities.
The Act directs the Division to develop the waters of the Bear River and its tributaries, according to a report prepared by the Utah Division of Water Resources. "The Division is to plan, construct, own and operate reservoirs and facilities on the river as authorized and funded by the legislature, and to market the developed water."
"The estimated cost to deliver the full allocation of Bear River Water today to the Weber Basin Water Conservancy District and the Jordan Valley Water Conservancy District is about $700 million with half the burden falling on the State to develop the water and deliver it to Willard Bay and half on the water districts to treat the water and deliver it to their wholesale agencies," according to project documents.
The Utah Rivers Council says there are alternative to diverting flows of the Bear River. "Water conservation and agricultural water transfers can eliminate the need for Bear River dams and diversions at a cost $4,000/acre-foot less than current proposals," according to information on the council website.
"It seems like a no-brainer that drying up the lake can't be good for the bird populations that use the Great Salt Lake ecosystem," Hicks said. "Someday it will come down to water for humans or birds. Today is the day to start trying to find some middle ground so that both may survive in this arid land."
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