New Online Flood-Mapping Tool Unveiled

By Tim Lee
Cobb Commission Chairman 

Earlier this week the U.S. Geological Survey unveiled a new web-based tool, called a "flood inundation map," that will help residents and emergency managers protect lives and property in the flood-prone Sweetwater Creek area.

Many Cobb residents recall the epic Atlanta floods of 2009 resulted in 10 deaths and more than $250,000,000 total estimated damages in a 7-day period. Floods impacted more than 20,000 homes and businesses and damaged hundreds of roads and bridges, according to Federal Emergency Management Agency.

At that time, Sweetwater Creek experienced the highest flows recorded in more than 108 years of measurement with a recorded 31,500 cubic feet per second—300 times higher than the creek’s normal flow.

This new tool will help identify where the potential threat of floodwaters is greatest, enabling emergency personnel from FEMA, state and local agencies to make quick decisions about when and how to evacuate residents. State and local officials will be able to use the interactive tool before the rain falls to better plan flood response and resource recovery, and to assess evacuation routes at various flood levels. 

Present at the unveiling were Joe Jerkins, mayor of Austell; Robert Mason, acting chief of the U.S. Geological Survey Office of Surface Water in Virginia; David Scott, District 13 congressman; Cobb Commission Chairman Tim Lee; and Keith Stellman, the meteorologist-in-charge of the National Weather Service in Peachtree City.

Flood inundation maps are based on real-time river gauge readings from the USGS’s nationwide streamgage network, which monitors water level and flow of the nation's rivers and streams. Users can identify locations that would be affected by flooding at different water levels from I-20 north through Austell.

In addition to the map, scientists are also installing a webcam along the creek near Legion Park to capture live streaming video, enabling people to monitor the creek’s water levels in real time. 

Residents can sign up for WaterAlert and StreaMail, online resources that provide timely information about river conditions at important locations. For additional information, please visit ga.water.usgs.gov