Seasonal peak flows not only raise Mono Lake, but also provide the dynamic energy needed to restore pools, riffles, and meander bends in the streams. They help willows and cottonwoods establish themselves along the banks, which in turn captures sediment and rebuilds stream banks. The high flows also can spread over the floodplain through the streams’ multiple channels or in seasonally rewatered side channels, raising groundwater levels for the recovering vegetation to tap into.

"What we are striving for is restoration of the habitat conditions that benefited the streams’ former fisheries and wildlife, as the court and the State Water Resources Control Board hoped to see," said Heidi Hopkins, Eastern Sierra Policy Director for the Mono Lake Committee.

While there are parts of the stream ecosystem that will never return to former conditions, the restoration efforts should help undo the damage, says Hopkins. The high flows this year should provide plenty of water to pine seedlings planted last year along Rush Creek by the Committee and Lee Vining Elementary School students. Restoration is expected to take many decades, as cottonwoods and pines -- seeded naturally or planted -- grow to maturity.

The peak flow on Rush Creek depends to a large degree on how Southern California Edison and DWP operate their dams and diversions. Upper Rush Creek passes through a series of natural lakes that were dammed to store water for hydropower production. The largest and most downstream reservoir is Grant Lake, which DWP traditionally used to store water for diversion to the City of L.A.

"Because there is no direct outlet from Grant Lake dam to provide high flows, at present high flows must be spilled over the dam," said Peter Vorster, hydrologist for the Mono Lake Committee. "This year there’s been good communication between DWP and SCE operators in the interest of providing Rush Creek with a healthy spring flood."

Flows on Rush Creek may peak around 450-500 cfs. This is less than what would occur naturally if there were no upstream dams.

When the State Water Resources Control Board ordered protection for Mono Lake in 1994, it also ordered DWP to develop restoration plans for Rush and Lee Vining creeks. Scientists hired to prepare the plans recommended relying primarily on natural processes – such as the high flows during early summer snowmelt -- to restore stream habitats.

The restoration plans currently are pending approval by the State Water Board. A decision is expected sometime this month that will guide flow requirements, restoration activities, and monitoring of the recovery for the next 10 to 20 years.

The Mono Lake Committee will be offering a seminar on restoration on August 29-30 led by Dr. Richard Ridenhour, one of the scientists who helped prepare the Mono Basin stream restoration plans. In addition, there will be numerous field activities related to restoration during the Committee’s Restoration Days on Labor Day weekend. For information, call the Committee at 647-6595 or visit the web site (www.monolake.org).