Rapid Deployment of Flood Warning System for County of Sonoma Following Devastating Wildfires

In October 2017, the Sonoma County region experienced several firestorms that left a blazing path of destruction and killed at least 25 people. In the aftermath, the communities faced a new danger as they struggled to recover. The resulting fire burn scars and ground conditions throughout the Tubbs and Nuns area had left the region highly vulnerable to life-threatening flash flooding and debris flows during heavy rainstorms. As they headed into California’s rainy season, Sonoma County and City of Santa Rosa officials knew that a flood warning network was needed as quickly as possible to assist the County and National Weather Service in detecting potential flooding conditions.


Led by Sonoma County Water Agency (SCWA) and working collaboratively with a team from OneRain and other local agencies, a plan was put in place to implement a new flood warning network for the region that would provide advanced warning for potential flash flood threats to the communities as they struggled to recover.

The timing and speed of installation of the new ALERT2-based radio telemetry network was critical. Strategic monitoring site locations within and downstream of the burn scar areas were chosen. OneRain conducted a radio path analysis and designed an optimized network plan that would leverage other existing ALERT2 networks in the area.

More than 25 HSE automated rainfall and streamflow gauges were installed by OneRain’s Field Services team. Soil moisture sensors were later installed to track saturation and potential slope destabilization in at-risk areas. OneRain’s Contrail® software platform provides SCWA with secure 24/7 real time data collection, archiving, monitoring, and visualization used in decision support. SCWA and other officials and responders receive advanced notifications of potential flood-threatening conditions via email and SMS. The data feeds sent from Contrail to the National Weather Service are used in developing their official active hazardous weather warnings and advisories. The general public can also view up-to-the-minute rainfall, streamflow, and other data at https://sonoma.onerain.com/.

The entire ALERT2™ Flood Warning network was fully operational in less than four months.


“The need on the heels of the October fires was imminent, and the pace at which we had to act was daunting. OneRain definitely stepped up to the plate to help us navigate this rapid deployment of our gauge network. Their expertise and professionalism were invaluable throughout the process,” said Jay Jasperse, Chief Engineer, Sonoma County Water Agency.



In a press release issued by the County of Sonoma and City of Santa Rosa, Brian Garcia, Warning Coordination Meteorologist with the National Weather Service said, “Knowing what is going on in real time is vitally important to the issuance of life-saving warnings, such as flash flood warnings. During rain storms we continually monitor the network of instrumentation across Sonoma County to maintain situational awareness.”


About OneRain Incorporated
Since 1992, OneRain has been providing solutions that optimize water management, heighten regulatory compliance, achieve successful civil works, and save lives. Headquartered in Longmont, Colorado, OneRain’s software and services deliver mission critical information to serve clients responsible for flood early warning, dam safety and reservoir operations, water resources, stormwater and wastewater management. For more information, visit www.onerain.com or call 800-758-RAIN (7246).


#wildfire #flashflooding #mudslide #debrisflow

New Rainfall Monitoring System for Flood Warning in Doña Ana County, NM

In the news November 2014: “New Rainfall Monitoring System to Aid in Flood Warning”. The Doña Ana County Flood Commission – in conjunction with the National Weather Service and other entities – has installed the first series of rainfall monitoring stations in Doña Ana County, data from which is available for viewing on the Internet.

The strategic placement of the monitoring sites is designed to predict flooding and enable a warning system for residents who may be in danger.

Doña Ana County Flood Commission Director Paul Dugie said the warning system represents an ongoing investment that augments diversion structures and dam maintenance with tool for residents to monitor rainfall in upstream areas.

“Residents of low-lying areas already know that it can be dry as a bone where they live, but if heavy rainfall is occurring in upstream areas, they can be at risk for flooding when the arroyos run,” Dugie said. “We view this system as one more important tool to protect lives and properties.”

Afton Weather Station – the very first ALERT2 site in Doña Ana County, Las Cruces, New Mexico.

The rainfall gauges all send data to a central tower on A Mountain east of Las Cruces, and a transmitter on that tower relays the information to the Doña Ana County Government Center, where it’s posted onto the Internet at https://weather.donaanacounty.org

Upon full implementation – which is estimated to be completed in 2017 – there will be 30 remote weather stations, stream gauges and water-level monitoring stations located throughout Doña Ana County, all of which will be linked to the National Weather Service and to other gauges in southern New Mexico and El Paso County.

“Not only will we be able to gather real time information with this system,” Dugie said, “but we’ll also be able to more closely track trends that will improve future forecast models.”

Dugie estimated that about $130,000 worth of equipment has already been integrated into the system, with an annual maintenance budget of about $30,000. In addition, he said his office has hired a flood warning system operator to oversee the system and its maintenance, both in the field and from the Doña Ana County Government Center.

In addition to Doña Ana County and the National Weather Service, other partners in the initiative include the Elephant Butte Irrigation District, the City of Las Cruces and New Mexico State University.

In addition to the rainfall gauges, a robotic camera has been acquired that can be used to monitor culverts for blockages and structural integrity, thereby improving the county’s ability to maintain and replace them before they fail. The robotic camera is attached to a specially equipped all-terrain vehicle that can access rugged areas in all kinds of weather. The recorded information and camera images can be saved to a central database.

News Source: https://donaanacounty.org/content/new-rainfall-monitoring-system-aid-flood-warnings
Read more about Doña Ana County’s flood warning system on the NM Climate Center’s blog: http://nmclimatecenter.blogspot.com/2014/11/new-rainfall-monitoring-system-for.html