The U.S. Army Corps of Engineers (USACE), Fort Worth District hosted members of Texas Division of Emergency Management (TDEM) at the Lewisville Lake Dam Dec. 9, 2020 to discuss risk management activities associated with the Lewisville Dam Safety Modification, as well as the planning and partnerships of related activities now and in the future.
USACE Fort Worth Dam Safety Project Manager Stacy Gray and Emergency Management Specialist Matthew Kennedy hosted six members of TDEM and Denton County Department of Emergency Services on a tour of specific areas related to the current construction efforts of the Lewisville Dam Safety Modification and to discuss the objectives of the project and how the resulting modifications will ensure the continued safe and effective operation of the dam.
“USACE strives to be open and transparent in communications related to risks at our dams,” said Gray. “We meet annually at a minimum with emergency management officials at all levels to communicate the risks and understand the risk mitigation planning done at city, county, state and federal levels. Just like schools, offices, and homes have a plan for fires and tornados, we are trying to ensure there is also a good plan for floods.”
The Dam Safety Modification is a result of a March 2014 assessment where Lewisville Dam was confirmed as a high urgency dam primarily due to potential loss of life consequences. The potential for foundation seepage, embankment instability or spillway instability or erosion could all result in a significant loss of life if they adversely affected the integrity of the dam.
“The dam continues to successfully perform all the functions it was designed for, and we have never experienced the extreme loading conditions modeled that could cause the dam to fail,” Gray said. “Life safety is our number one priority at USACE, and the potential for loss of life if these extreme storms and loading conditions were to occur lead to actions on the part of USACE to reduce the risk to the public as much as possible.”
All work on the earthen embankment, the first of three separate actions for the Lewisville Dam Safety Modification, is currently under construction. USACE anticipates award of the construction in the spillway in 2022. The restoration portion of the project will be completed in part by the contractor selected for spillway construction, and by the Lewisville Aquatic Ecosystem Research Facility.
While maintenance and operation of the dam are the responsibility of USACE, partnerships with other government organizations are necessary and integral in flood risk management, flood response and post-flood response.
“Our communication, coordination and collaboration are absolutely vital for us to get the right information and resources to the right people in the right time during a flood emergency,” said Josh Roberts, assistant chief, TDEM serving Region 1. “Visits like this are important to keeping TDEM and USACE in sync because it helps us understand each agency’s latest risk management and preparedness efforts and helps us maintain the close partnership.”
The value of this partnership was made evident in Spring 2015 when North Texas and Oklahoma were hit with record rainfall and tornado outbreak. Eric Hutmacher, assistant emergency management coordinator at Denton County Department of Emergency Services, first worked in partnership with USACE in early 2015 executing a simulated, or “tabletop,” flood response exercise, never knowing that experience would be put into play just a few months later.
“No one knew that the exercise scenario was going to play out in real life later that spring and summer,” Eric said. “Just a couple of months after the tabletop exercise, successive weather systems brought heavy rains and severe weather to North Texas and the lakes in the Trinity River Basin began to fill to eventually activate uncontrolled spillways in our jurisdiction. Our team worked directly with USACE to share information and address public concerns which resulted in a partnership that has grown since that historic year.”
Floods are the number one threat to life safety from severe weather events in North Texas and mitigating that threat greatly assists the safety of residents. In accordance with Public Law 84-99, USACE may supplement state, tribal, territorial, and local governments with flood or coastal storm preparedness and response services and advanced planning measures designed to reduce the amount of damage caused by flooding.
“While USACE can address the probability side of the risk equation, we need help from city, county and state leaders as well as the public at large to manage the consequences side of the risk equation,” said Gray. “Understanding the risk, knowing what to do if the worst happens, and how much time you have to react is an important part of reducing the loss of life that could occur during a catastrophic event.”
Lewisville Lake Dam was placed into operation in 1954 and serves the citizens of North Texas providing flood risk management, quality water supply, environmental stewardship and recreational opportunities. The Corps of Engineers tests, evaluations and subsequent required work are ongoing to ensure that the 66-year-old project will continue to safely provide these important services.
“Hopefully there is never an emergency at one of our dams. But if there is, through these relationships and workshops we know who to contact and that we have a good plan to get people to safety as quickly as possible,” said Gray.
Please see the website for your local emergency management office for information on how to prepare for and respond to all types of emergencies where you live.
For more information on the Lewisville Dam Safety Modification, visit https://www.swf.usace.army.mil/Home/Lewisville-Lake-Dam/
For more information on Texas Division of Emergency Management, visit https://tdem.texas.gov/
To learn more the Fort Worth District’s Emergency Management Mission, visit https://www.swf.usace.army.mil/Missions/Emergency-Management/
Join our online community by visiting https://about.me/usacefortworth