Significant Rain Event at Amistad National Recreation Area Increases Water Levels to Near Record Levels

A significant rain and flooding event took place upstream from Amistad National Recreation Area from July 2 through July 6, 2010 as a result of the remnants of Hurricane Alex. Although Tropical Storm Alex remained in Mexico, bands of heavy rain have persisted along the Rio Grande River for four days. As a result, Amistad Reservoir has risen over 16 feet since the rain event began on July 2. The lake level reached a high elevation of 1130 feet above sea level on July 6. Maximum capacity for the reservoir is 1145 feet above sea level. Lake Amistad has not been at this level since 1974. The lake is now slowly dropping in elevation at a rate of eight inches per day. The lake elevation will continue to fluctuate up and down based on any new rainfall that may fall on the watershed, and any changes to the release rate from Amistad Dam. The International Boundary and Water Commission (IBWC), a branch of the U.S. State Department, is the agency responsible for operating Amistad Dam, and for determining how much water is released from the dam. The IBWC is currently releasing 35,000 cubic feet per second (cfs) from the dam, which is significantly more than the 1,165 cfs that is normally released.
Visitor safety is a primary concern of the National Park Service, and although many of the parks’ boat ramps are open to boat launching by the public, boaters need to pay attention to floating debris on the lake as a result of the recent flooding. Boaters are encouraged to avoid large rafts of floating river cane. The small particulate matter floating with the river cane, which looks like sawdust, can get sucked up into the water intake of your boat motor, obstructing the screen to your water pump, which could result in boat motor failure. In addition, large logs and other hazards may be found anywhere on the lake at this time, since flood waters came down all three of the rivers which feed Lake Amistad, the Rio Grande, the Pecos River, and the Devils River between July 2 and July 6. Most boat ramps remain open to public boat launching, but some are closed because the access roads are flooded, making some of the ramps inaccessible. To check the status of boat ramps at Lake Amistad, visit our park web site at www.nps.gov/amis. At the present time, ...