Users can also access historical flood information and potential loss estimates based on the severity of the flood. 0000000975 00000 n Folsom Dam Nimbus Dam You can contact the floodplain hotlines for flood zone information including information on local floodplains and repetitively flooded areas. Dam Failures and Lessons Learned Seminar. An area of potential flooding shown on a map as an area which will be inundated if a dam fails. We operate and maintain the State Water Project and support sustainable groundwater management. Chose an area/neighborhood to view potential flood concerns, how fast locations may receive water, and which directions to go to escape. 5.1 Identifying and Profiling Dam Failure Hazards . Construction of the dam began in 1951 with preliminary excavations for the Folsom Power Plant. at selected USGS streamgages. [n 1] The dam and appurtenant dikes total a length of 26,730ft (8,150m), more than 5mi (8.0km). The USGS Flood Inundation Mapping (FIM) Program helps communities protect lives and property by providing tools and information to help them understand their local flood risks and make cost-effective mitigation decisions. These are to help you think of how to escape before an emergency occurs. 0000004955 00000 n Inundation should be depicted on suitable base maps, such as USGS topographic quadrangles, orthophotos, or equivalent, and should extend downstream of the dam to a point where the projected or estimated increase in water level due to dam failure, as derived from a dam break analysis, would no longer present a danger to life or property. Totally, twenty villages get affected among which seventeen are severely affected. The 340-foot high concrete gravity Folsom Dam along with two earthen wing dikes on each of its sides create Folsom Lake. Folsom Dam is located just north of the city of Folsom, and consists of a 340-ft-high (100 m), 1,400-ft-long (430 m), hollow-core, concrete gravity dam containing 1,170,000cuyd (890,000m3) of material. DI-1 Reduction of the potential for the loss of life from dam failure inundation by developing emergency preparedness plans. California Government Code Section 8589.5 An Inundation map shows flooding that could result from a hypothetical failure of a dam or its critical appurtenant structure. Winter rains of 2017 brought widespread flooding to California Seattle: Association of State Dam Safety Officials. View approved inundation maps. About NHDs - California Natural Hazard Zone Disclosure | NHD Report Geological Survey science in the decade 20072017, Earth Resources Observation and Science (EROS) Center, Delivering integrated HAZUS-MH flood loss analyses and flood inundation maps over the Web, Sources of uncertainty in flood inundation maps, April- First preliminary FIM website, guidance, and templates released online, June- First FIM coordination meeting in Atlanta. Our work in statewide flood forecasting and flood operations help reduce flood risk. The window can be minimized by clicking the 'collapse' icon. The USGS provides these maps as-is for a quick reference, emergency planning tool but assumes no legal liability or responsibility resulting from the use of this information. Below Aging U.S. Dams, a Potential Toxic Calamity - Route Fifty 0000001524 00000 n This suggests that the failure resulted from a condition that changed over time; specifically, there was a gradual increase in the coefficient of friction at the pin-hub interface. [34], The New Year's Day storm of 1997 was the most severe in recent history, with a total inflow of 1 million acre feet (equal to the entire capacity of Folsom Lake) over a 5-day period. 0000004028 00000 n 0000003485 00000 n The maps provide information about a hypothetical failure of a dam or its related structures, such as a spillway or outlet, to assist in emergency preparedness and planning. Find local businesses, view maps and get driving directions in Google Maps. AN AREA OF POTENTIAL FLOODING shown on a dam failure inundation map pursuant to Section 8589.5 of the Government Code. Maximum Inundation Depth (feet) <1 1 to 2 2 to 5 5 to 10 10 to 20 >20 Cities #*Dams Fire Stations!.Road Callouts Santa Clara County Inundation Map for the Hypothetical Fair Weather Failure of Stevens Creek Dam Federal Dam ID: CA00292 State Dam ID: 72-007 Sheet 1 of 12 1 in = 1,000 ft Dam Owner: Santa Clara Valley Water District 5750 Almaden Exp Current construction improvements include addressing minor runoff, drainage and erosion conditions at the Right Wing Dam. The forensic report documenting the failure of the Folsom Dam gate revealed the cause of the malfunction to be excessive friction at the 32-inch diameter trunnion pin, or pivoting mechanism. Users can also access historical flood information and potential loss estimates based on the severity of the flood. Apple River System - Riverdale Dam to St. Croix River Chippewa River System - Riverdale to St. Croix River Folsom Dam Hydrologic Dilemma Folsom Dam was originally designed to reduce flood flows on the American River to a flow rate that could be contained by the downstream levees. When available, flood inundation layers can be toggled on or off within the map. The purpose of a dam is to store water, or . On July 17, 1995, when Folsom Lake was at full capacity, a Folsom Dam operator attempted to open Gate #3 to maintain the flow of the river during a scheduled power plant shutdown. USACE Publishes Policy Update for Inundation Maps and the National