Mansker Basin study to support flood preparedness

Lacey Thomason, Tennessee Silver Jackets project manager with the U.S. Army Corps of Engineers Nashville District, gives administrative announcements during the quarterly meeting with federal, state and local partners at the Tennessee Emergency Management Agency Headquarters in Nashville, Tenn., Oct. 31, 2017. (USACE photo by Leon Roberts)
Lacey Thomason, Tennessee Silver Jackets project manager with the U.S. Army Corps of Engineers Nashville District, gives administrative announcements during the quarterly meeting with federal, state and local partners at the Tennessee Emergency Management Agency Headquarters in Nashville, Tenn., Oct. 31, 2017. (USACE photo by Leon Roberts)

By Lee Roberts

NASHVILLE, Tenn. (Oct. 31, 2017) – The Tennessee Silver Jackets team announced today that a one-year study of the Mansker Basin is underway to develop real-time simulation modeling for Sumner and Davidson Counties and the cities of Nashville, Millersville, Goodlettsville and Hendersonville.

The Mansker Basin covers 47 square miles and extends from Millersville through Goodlettsville to the Cumberland River.  It experienced significant flooding in recent years, most notably in May 2010 when 293 structures were damaged costing $32 million.

Brantley Thames, engineer on the project with the U.S. Army Corps of Engineers Nashville District, briefed federal, state and local partners at the Tennessee Silver Jackets quarterly meeting at TEMA headquarters on the Mansker Real-Time Simulation Pilot Study, its official title.

He noted that the Silver Jackets team will utilize tools from the Corps of Engineers, National Weather Service, and U.S. Geological Survey to develop a flood-warning product.  They will build on real-time forecasting models that have already been developed for the Nashville Situational Awareness for Flooding Events (SAFE) program, an internal mapping tool to help Metro better predict where and when flooding will occur.

“We’re just getting started.  We’re compiling the existing models and data that we have and we’ll get that set up to import into the RTS system, Thames said.  “And we’re also coordinating with the Weather Service to fill some data needs that we still have, especially with how they relate to forecasted precipitation.”

Thames said the goal is to have a real-time forecasting model that will cover the entire Cheatham watershed, which is an exciting prospect for flood preparedness officials and responders.

“More accurate data will help local emergency managers and floodplain managers better understand, plan for, and respond to flooding events in the basin,” said Patrick C. Sheehan, TEMA director.  “The Tennessee Silver Jackets team looks forward to constantly moving toward the vision of developing comprehensive and sustainable solutions to natural disasters.”

To enhance flood risk management efforts, the National Weather Service has already established action and flood stages for the Manskers Creek gage near Millersville.   With info from the study, the NWS will be able to run various high water scenarios and visually examine the impacts for developing flood warning products.

James LaRosa, service hydrologist with the Nashville Forecast Office, said the study will provide valuable information about Manskers Creek that will be used to create inundation layers for various flood scenarios and generate water levels based on current rainfall.

“This will provide some lead time to residents that may be affected by flooding and give them time to respond before flooding develops,” LaRosa said.

The Corps of Engineers’ real-time simulation modeling will help USGS develop its stage-discharge rating curve at the Mansker’s gage. NWS will be able to run various high water scenarios for the development of flood warning products and develop actions and flood stages for the USGS gages. Local emergency managers would utilize these flood warnings and action levels to know when to close roads and plan for evacuations.

“More accurate warnings will help local emergency officials to better respond to flooding events in the basin, which will improve public safety,” said Lacey Thomason, Silver Jackets coordinator with the U.S. Army Corps of Engineers Nashville District.

The Corps of Engineers Silver Jackets Program is funding the one-year, $50,000 study, which is only possible due to the multi-agency effort since the May 2010 flood. Other Silver Jackets partners are providing work in kind in support of the project.

The Tennessee Silver Jackets team vision is to establish and strengthen partnerships at the local, state, and federal level as a means for developing comprehensive and sustainable solutions to natural disasters. The team facilitates flood risk reduction, coordinates programs, promotes cohesive solutions, synchronizes plans and policies, and ultimately provides integrated solutions with initiatives like the Mansker Basin study.