Salt Lake County has chosen a less expensive flood-control plan to protect homes and property near 5,700 acres of Emigration and Killyon canyons charred by the Affleck Park fire earlier this month.
The county will build as many as 120 small check dams on eight canyon forks in the burned area, instead of constructing six large debris catchbasins as originally planned - a change that could save nearly $500,000.Shortly after the fire, the county applied for $800,000 in federal emergency funding to build those catchbasins and for $100,000 more to help fund a joint program with the state and Salt Lake City to reseed the burn area.
The loss of slope cover in the burn area increased potential for erosion on seven canyon watersheds by 700 percent, threatening loss of life and property in the event of heavy rainfall, according to a report by the county geologist and the federal Soil Conservation Service
The danger would come primarily from eroded topsoil and sediment that could block natural drainages, causing creeks to leave their banks. The resulting floods could damages homes, other structures and public utilities, the report said.
To mitigate that flooding danger, the county will build check dams in Secret Canyon, in four forks of Killyon Canyon and on Freeze, Hairpin and Brigham creeks. The county has already approved a low bid for the work in Secret Canyon and engineering work is being done for other the areas, said Romney Stewart, the county's acting public works director.
As many as 20 check dams will be built on each watershed to prevent runoff of silt and debris, Stewart said. The entire flood-control project is expected to cost $320,000 and will be funded by the Soil Conservation Service.
Revegetation of the burned area is expected to take between three and five years.