Experts preparing flood map that balances both safety, natural aspects of the Carson River

Despite near-drought conditions in Northern Nevada this winter, officials continue to plan for floods in the Carson River Watershed - an inevitable event along the waterway that cuts through four counties.

Ed James, general manager of the Carson Water Subconservancy District, who recently came to the Carson City Board of Supervisors seeking support for a floodplain risk charter, said the plan is necessary because people within the four counties want the river to remain natural.

"People don't want the Carson River to be a channel. They want a living river," James said.

Although the most recent flood in Carson City was in 2006, he said, at the height of the flood of 1997, 25,000 cubic feet per second of water was rushing past a gauge in the Carson River.

The charter will be a collaborative effort between local, state and federal agencies to identify and plan for flood risks within the watershed, which includes parts of California's Alpine County, Douglas County, Carson City and Lyon County to the Lahontan Reservoir, where the map stops.

"Lahontan was originally designed for flood control," James said.

In his report, James said that all counties along the Carson River adopted a Carson River Watershed Floodplain Management Plan in 2008, a plan that outlines long-term goals for managing the floodplain.

For the last six months, the CWSD has been working with the Federal Emergency Management Agency, the state, local flood administrators and other federal agencies to create a charter.

It represents a good-faith effort by all parties to work together, James said. It does not legally bind communities.

The maps date back to the 1980s, James said, so new efforts are long overdue.

The CWSD board signed the charter in October and directed its staff to present it to the counties

"In Carson City, you have a lot of alluvial fan flooding impacts, but this study focuses on the river," James said.

Rob Fellows, Carson City's flood manager, said there are different sets of guidelines for each type of flooding, but the results are ultimately the same, even though measures to lessen impacts are quite different.

"If Douglas does something that pushes water through Carson City faster, it could have an impact on us," he said.

James said most of Carson's flooding comes from the watershed, and Fellows has done a lot of work to minimize damage. The city also has done a good job of purchasing land along the river, which prevents homes from being in the wrong place at the wrong time.

"I'd give them an 'A' for that," he said. "They've been very proactive at protecting those areas, and they've done a lot with the range, too."

The charter goals are based on identification and mapping of floodplains to create an awareness of hazards and to provide the data necessary to help communities plan for flood management, James said.

"We'll all be on the same page, and there will be uniformity for everthing, and for everyone," he said.

The mapping program is expected to provide the following benefits to watershed communities such as Carson City, as well as to property owners and citizens:

• Increased public awareness and action to reduce risk to life and property.

• Ability to build upon flood hazard data and maps produced during the flood map modernization program.

• Assessments of present and future risk.

• Ability to address gaps in flood hazard data to form a solid foundation for risk assessment and floodplain management, and provide information needed to ease flood-related risks.

• Protection of the natural and beneficial function of drainage-ways and floodplains, including trail corridors, parks, recreation, wildlife habitat, flood storage and groundwater recharge.

• Create good-neighbor policies throughout all the communities in the watershed.

The first phase, for Lyon County, is almost complete, while work on Carson City's portion is just getting started, James said.

"In three years, we should have the model completed to Alpine County," he said.