Flood coalition meeting Aug. 19 | RecordCourier.com

Flood coalition meeting Aug. 19

by Christy Chalmers

Members of the Buckbrush Wash Flood Coalition have always known the Johnson Lane area is prone to flash floods.

What they didn’t know is that the Buckbrush wash flood zone behaves differently than previously believed, and that the Johnson Lane wash, a separate system to the south, might be a bigger, greater threat than Buckbrush.

The findings were made by Dr. Kyle House of the Nevada Bureau of Mines and Geology.

John Cobourn, a Johnson Lane resident and hydrologist who acts as a technical advisor to the flood control group, said House will present the report Thursday during a coalition meeting at the Johnson Lane Fire Station.

Cobourn said a University of Nevada, Reno grant paid for House’s work, which was intended to lend scientific credence to what many Johnson Lane residents have experienced. The coalition formed in 1994 to study ways of controlling the flash floods that occasionally pour out of the Pine Nut Mountains through the washes that empty into the Johnson Lane area.

“What we have learned is that the flood zone behaves a little differently (along Buckbrush) than we thought,” said Cobourn. “It’s a pretty significant finding for the people of the Johnson Lane area, especially those in the Stephanie Way neighborhood.”

The Buckbrush wash hazard zone is narrower above Fuller Avenue and wider below, leading House to conclude that the water most likely will stay in or near the channel above Fuller but will spread out below.

“We thought that it might behave that way further up, and the scientists are saying it will probably stay confined close to the current channel area until it gets to Fuller,” said Cobourn. “When it gets below Fuller, it could widen and the channel could change directions or go straight.”

House also made another, previously unexplored observation about the Johnson Lane wash. Cobourn said House wants to do more research, but preliminary conclusions suggest the Johnson Lane wash could be a greater threat than Buckbrush.

Cobourn said House studied the Johnson Lane wash channel and found large boulders, which suggest stronger storm flows.

“The water has to be deep and fast to carry big boulders, and more, bigger boulders were found in the Johnson Lane wash than the Buckbrush wash,” said Cobourn. “We also know that each one has its own sub-watershed, which is the area that feeds it. Johnson Lane has a sub-watershed that is twice as big as Buckbrush.”

With those findings, the coalition will now have to decide how to proceed. Options include studying both washes or forming a sister coalition to study Johnson Lane. The group has broached the idea of a diversion structure in the Pine Nuts, but no decisions have been made.

“It’s up to the people. They each kind of threaten separate parts of the Johnson Lane area,” said Cobourn. “We will focus more on the Buckbrush side, but certainly (House) will answer questions about the Johnson Lane wash also. It’s probably the most scientific information we’ve gathered in the five years we’ve been together.”

What: Buckbrush Wash Flood Coalition meeting

When: 7 p.m. Thursday at the Johnson Lane Fire Station, 1450 Stephanie Way

Details: University of Nevada Cooperative Extension, 782-9960.