Thurmond Lake Hydrilla Update

Last week we asked our readers for topics they would like us to cover on Balancing the Basin; and we received several questions about hydrilla at J. Strom Thurmond Lake. This post provides an update on the hydrilla issue and potential treatment.

Hydrilla, an invasive aquatic plant, has gradually expanded its reach along Thurmond Lake’s shoreline since the mid-‘90s. Hydrilla is present along approximately 53 percent of Thurmond’s shoreline. Since water depth and available nutrients limit its growth, hydrilla only impacts about 7 percent of the lake’s total surface acreage.

Hydrilla is linked to the spread of Avian Vacuolar Myelinopathy (AVM)—a disease tied to a number of deaths in American Bald Eagles and various species of waterfowl.

We posted a detailed update about hydrilla in December 2013. This post is still relevant and accurate, so we encourage you to take a look if you haven’t already seen it.

The future of hydrilla treatment at Thurmond Lake depends on receiving federal funding from Congress and/or funding from other federal, state, and local governments. Total funding for all Thurmond Lake programs has been substantially reduced for fiscal year 2014. We requested funding in the 2014 budget for an Environmental Assessment to evaluate the impacts of using sterile grass carp to treat hydrilla, but that funding was not approved by Congress.

Corps staff will monitor hydrilla growth throughout the summer growing season (May through September). We will identify and prioritize treatment needs (via herbicides), but funding may only be available to treat major Corps boat ramps that have serious hydrilla impacts. The treatment plans will be coordinated with the Georgia and South Carolina Departments of Natural Resources, local agencies and affected out-grantees.

We are in the early phases of putting together a bi-state team to develop a new AVM Management Plan to address AVM at Thurmond Lake. Currently, hydrilla treatment is managed within the Corps’ annual Aquatic Plant Management Plan, but this new project would create a separate management plan solely focused on hydrilla and AVM with support and expertise from state natural resource agencies. This spring we met with representatives from the Georgia and South Carolina DNRs to discuss this project.

Click here to read the 2014 Aquatic Plant Management Plan.

Click here to read the survey results from the University of Georgia public opinion survey on hydrilla and grass carp.

We welcome your comments and questions in the comments section below.

~Tracy Robillard, public affairs specialist



About US Army Corps of Engineers Savannah District

The U.S. Army Corps of Engineers Savannah District oversees a multi-million dollar military construction program at 11 Army and Air Force installations in Georgia and North Carolina. We also manage water resources across the Coastal Georgia region, including maintenance dredging of the Savannah and Brunswick harbors; operation of three hydroelectric dams and reservoirs along the upper Savannah River; and administration of an extensive stream and wetland permitting and mitigation program within the state of Georgia. Follow us on Twitter @SavannahCorps and on
This entry was posted in Fish and Wildlife and tagged , , , , , , , , , , , , , , , , , , , . Bookmark the permalink.

3 Responses to Thurmond Lake Hydrilla Update

  1. Ferris says:

    Tracy, thank you for the update. I very much appreciate the requirement for an Environmental Assessment before introducing a non-native species, even though 76 bald eagle mortalities documented through last year are believed to be related to AVM according to Jeff Brooks, a wildlife biologist at the Savannah USACE office. Briefly scanning the literature reveals several questions, and I imagine USACE has many more.
    – Even though GA DNR requires individually tested sterile triploid grass carp, has it been 100% effective in practice? The number of fish required for the project leaves less room for error than in an small pond, and two fertile fish of different sexes could create a permanent problem. Do suppliers sometimes cheat in spite of penalties?
    – A 1998 UG study revealed that lifespan varies between 10 and 15 years with an effective vegetation control life of 8 to 10 years, so what would be expected in Thurmond? Small carp are devoured by bass, but larger carp cost more and have a somewhat shorter effective lifespan; so what size carp to use, and how many per acre?
    – Adult carp are huge- how will that affect the lake?
    – Will carp affect our native vegetation?
    I hope congress can soon be convinced to provide funding to assess solutions for the hydrilla/AVM problem so that we can protect our bald eagles and other affected bird species. ~Ferris

  2. yu nah ee tah says:

    I used to work for the federal government in the fiscal year budgeting process. How would I go about getting the name of the person on whose desk the hydrilla EA funding request died? It is so easy to say “Congress” did not approve funding but at some point it was a person who has a name and usually an agenda. If this post needs to be forwarded to the appropriate Freedom of Information officer in Savannah, give Miss Kerry my regards. Yes, I just used the magic word – FOIA. If I need to put all the bells and whistles wording in this request, please let me know. Any document that has this person’s name/contact on it will suffice.

    Ferris’ concerns were addressed years ago at the Walter F. George reservoir in on the GA/AL line. That project had similarities – two states dodging responsibility until the United States Army Corps of Engineers just took control and got rid of the hydrilla.

    In October 2010, at Lake Spivey near Atlanta, Henri-Christophe Bourget went into the water
    to retrieve a friend’s basketball, became entangled in the hydrilla, was pulled
    underwater and drowned. Divers could not find Henri-Christophe because the hydrilla
    was so dense. The lake had to be drained to find the athletic teenager’s body.

    Clayton County officials put grass carp in Lake Spivey the day after Dr. Susan Wilde, UGA made that
    recommendation. Jean-Claude and Miyoshi Bourget, Henri-Christophe’s parents, take
    little comfort in this.

    • US Army Corps of Engineers says:

      Thanks for your comment. FOIA requests submitted to the Savannah District will only yield information from records created by or belonging to the district. For records on decisions made in Congress, please start by contacting your appropriate representative. ~Russell Wicke