County seeks flood forecasting model for SLR River

The San Diego County Flood Control District will be applying for six National Oceanic and Atmospheric Administration grants, including one to develop a flood forecasting model for the San Luis Rey River.

The San Diego County Board of Supervisors, which also acts as the board for the flood control district, voted 5-0 September 27 to authorize the application for the six grants and their subsequent acceptance if awarded. The six grant proposals to NOAA total $263,960, and no local match is required. The grant request for the flood forecasting model for the San Luis Rey River is for $50,000.

“There is a Federal grant available out there that would basically help our ability to do flood forecasts,” said Cid Tesoro, the program manager for the county’s Watershed Protection Program.

The flood control district has a system of 100 automated weather gauges which monitor real-time changes of rainfall, stream level, lake level, and various weather factors. The system is known as ALERT (Automatic Local Evaluation in Real Time) and is monitored to identify regions of potential flood activity. If flooding is observed or expected, the appropriate agencies are notified to provide timely warnings to the public. ALERT also includes automated stations which control access to low water crossings, watershed models to forecast flood events, and Internet access to real-time weather and streamflow data.

NOAA has an annual Automated Flood Warning Systems Grant Program to help local jurisdictions improve the accuracy of flood warnings. The goal of the NOAA program is to support the creation, renovation, and enhancement of locally-operated rain and stream gauge networks and automated flood warning systems which would achieve changes in flood warning systems to improve the safety of lives and property in communities with flood and flash flood problems.

County staff (flood control district projects are normally handled by the county’s Department of Public Works) identified six projects which could be undertaken with the NOAA grant funding. In addition to the San Luis Rey River flood forecasting model, the requested grants are for $79,200 to update rain gauges, $50,000 to purchase data maintenance and analysis software, $40,000 to develop a real-time flood warning public Website, $30,000 to install Internet-accessible low water crossing cameras, and $14,760 to convert certain stations to National Weather Service standards.

The data maintenance and analysis software would be an automated system. “The alert system provides us a means of analyzing the rain patterns coming into the county,” Tesoro said.

That would provide advance warning not only to the flood control district but also to the county’s Department of Emergency Services and the Sheriff’s Department, agencies with whom the flood control district work in order to notify communities. The system would determine if a particular community would be in jeopardy. “That way you’re not notifying everybody, only the areas that would be potentially affected,” Tesoro said.

The flood forecasting model for the San Luis Rey River would be the second such river-specific model for the flood control district. In 2005 the district undertook a pilot program for the San Diego River which developed a flood warning system based on rainstorm events and river elevation. “We had pretty good success with the pilot program, so now we’re looking at other areas,” Tesoro said.

The San Luis Rey River is the next site for the forecasting project. “This would give us a chance to help with the predictive flooding,” Tesoro said.

The San Luis Rey River is 51 miles in length and is mostly riparian. It runs from Lake Henshaw to the Pacific Ocean. “It was chosen because of our concerns for the population in the area,” Tesoro said.

Tesoro also noted that the county’s heavy rainfall areas include the upper portion of the San Luis Rey River. “It just made logical sense that we look at that river next,” he said.

Tesoro explained that the San Luis Rey River flood forecasting model was more of a forecasting tool than the data maintenance and analysis software. “They both go hand in hand,” he said.

The public Website is also in conjunction with the other grants. “We wanted to be able to provide a means to the public to take a look at the information we obtained,” Tesoro said. “There’d be a resource for them to go to.”

The flood control district is hoping to hear from NOAA by the end of 2006 about the success of the grant applications. “Hopefully we’ll be successful in the grant application and we’ll get this up and running as quickly as possible,” Tesoro said.