Precautionary Flood Fight Efforts at Grenada Lake Dam Spillway

The U.S. Army Corps of Engineers (USACE) Vicksburg District (MVK) is taking precautionary flood fight measures at the Grenada Lake Dam in Grenada, Mississippi, due to forecasted rainfall in the region.

District engineers began making preparations to place stone in the spillway March 8. The stone will be placed over gabion baskets that are currently in the bottom of the spillway channel to further armor the channel in advance of additional rainfall forecasted at the lake in the upcoming weeks.

The reservoir at Grenada Lake Dam is currently at an elevation of 225.1 feet, and the project’s spillway is at an elevation of 231 feet. Based on current water on the ground and the National Weather Service’s precipitation forecasts, Grenada Lake’s elevation has the potential to come within a few feet of the spillway crest within the next few weeks.

Grenada is one of four flood control reservoirs in Mississippi maintained and operated by MVK. The district’s four Mississippi flood control reservoirs – Enid, Grenada, Sardis and Arkabutla lakes – are used to hold runoff, or excess rainwater, as a flood-prevention measure. MVK used these four flood control reservoirs to reduce the peak flow of rainfall runoff by approximately 90 percent during the unprecedented rainfall event throughout the region in February 2019. During the rain event, the reservoirs each held an average of nine inches of rainfall runoff, which generated an estimated 320,000 cubic feet per second of combined inflow into the reservoirs.

The district will continue to monitor water elevations throughout the region and will issue an update if a change in forecast indicates that spillway flow at Grenada is imminent.

MVK is conducting daily patrols across the entirety of its jurisdiction as a part of its flood fight efforts due to elevated river stages across the region. MVK technical experts are deployed inspecting and monitoring flood control works, such as levees, floodwalls, reservoirs and relief wells, to ensure that these features continue to function as designed. These patrols will continue as long as elevated water levels persist. The district has observed no significant issues at any flood control sites.

MVK has approximately 60 personnel working to support local, state and federal officials with technical expertise and flood-fight material as needed.

Citizens are encouraged to contact their local authorities and emergency management officials for updates about conditions in their area and should avoid activities on or near flood control works.