ALERT 2™ Real-time Monitoring for Automated Flood Warning
ALERT2 Protocol Improves Data Collection Capabilities for Automated Flood Warning Systems (AFWS) and Environmental Monitoring.
ALERT2™ is the new standard protocol designed to replace ALERT (Automated Local Evaluation in Real Time). ALERT2 provides a graceful transition of real-time data collection systems from providing slow, lean, error-prone environmental data to receiving fast, information-rich, error-free knowledge about events in the real world.
ALERT2 has many benefits
- Faster by more than 10 times; much greater system capacity
- Full error detection and forward error correction; good data or no data
- Use of time division multiple access (TDMA); GPS-accurate clocks and no more traffic jams
- Large identifier fields; many more site and sensor identifiers
- Unlimited message content; full engineering values, rich information
- Protocol can be extended to support custom messaging needs
Initiated in the mid-2000s, the open standard is trademarked by the National Hydrologic Warning Council and developed by the ALERT2™ Technical Working Group, a subset of the Standards & Guidance Committee. The primary ALERT hardware and software vendors are all committee participants, as are U.S. and Australian agency members. This new standard is being adopted by multiple vendors to offer customers competitive choices.
The latest version of the ALERT2 Standard documents are currently posted at www.hydrologicwarning.org.
ALERT2 Source Address Management
ALERT2 Source Address Management System (SAMS) is a web-based application that tracks the agencies, their identifiers, and assignments of Source Addresses to those agencies.
Transition Path - ALERT to ALERT2
ALERT2™ is designed to provide a graceful, cost-controlled transition path for existing ALERT systems. First, the repeaters in the system are upgraded to ALERT2™ Concentrators, which receive both ALERT and ALERT2™ reports and transmit ALERT2™ messages to the base station. This hybrid system model allows agencies to replace hardware at gauging sites when it’s convenient and they have money to do it, yet improve their overall performance immediately and perhaps dramatically by increasing the capacity and eliminating transmission errors on the “last hop.”
OneRain Leads the Way in Implementations of ALERT2
OneRain has led the first three implementations of the standard, one for the Urban Drainage and Flood Control District (UDFCD), Denver, CO, the second for the Overland Park, KS, Flood Warning Decision Support Project and Stormwater & Traffic Operations Center Integration Project, a regional system that includes the Kansas City, MO, gauging network (OP/KCMO), and the third for the Harris County Flood Control District that covers the region around Houston, TX.
The performance of these first three implementations has been excellent. The comparative performance statistics in the UDFCD system are striking: Only about 1 in 10,000 ALERT2™ reports were lost, compared to 2-4% of ALERT transmissions during modest rainfall events. Data losses as high as 70% have been observed in large ALERT networks during storms, so the contention-free ALERT2™ channel will make enormous contributions to improved data collection.
ALERT2™ is a trademark of the National Hydrologic Warning Council (NHWC)