12 Dec Aquatic Vegetation Increasing in Smith Mountain Lake
By Joanne Houpt, SMLA Submerged Aquatic Vegetation Committee
The annual inspection of submerged aquatic vegetation (SAV) in Smith Mountain Lake has revealed expanded growth, but nothing abundant enough to be a nuisance.
Vegetation observed varied from native non-invasive SAV such as chara and pondweed to invasives such as hydrilla and brittle naiad. Some weed beds were very sparse, and some were a bit more significant.
History of Managing SAV at SML
In 2013, the Tri-County Lakes Administrative Commission (TLAC) introduced 6,000 triploid (sterile) grass carp into Smith Mountain Lake (SML) to combat invasive SAV such as hydrilla. The hydrilla and other invasive plants had become dense and problematic in some channels, marinas and around boat ramps.
The carp typically have a life span of approximately 10 years. Since their release in 2013, they have eaten most of the hydrilla and most of the other non-native invasive and native SAV in the lake.
The fish have reached the end of their expected lifespan so the increase in SAV is not unexpected. In 2023, sparse regrowth was observed and in 2024 more growth was found.
SMLA and the Scruggs Volunteer Fire and Rescue Dive Team Monitor SAV in the Lake
Since 2020, SMLA has worked with the Scruggs Volunteer Fire and Rescue Dive Team to perform spot checks at locations of past invasive SAV beds to monitor for regrowth. The divers are trained by SMLA to identify native and non-native plants. While conducting their practice dives, the team is supporting SMLA in its annual inspection goals.
The annual SMLA SAV inspection results are reported to TLAC, which takes responsibility for treating SAV that becomes a nuisance.
Citizens Encouraged to Support Efforts to Assess Lake Aquatic Vegetation
SMLA, TLAC, Appalachian Power (APCO), the Department of Wildlife Resources and others who comprise the Aquatic Vegetation Technical Review Committee (AVTRC) collectively review SMLA’s inspection findings along with the annual report issued by APCO’s contractor that inspects hundreds of sites at SML.
The AVTRC weighs the need for a more extensive, full-lake survey. So far, the SAV that is re-emerging is not dense enough to be problematic and does not warrant a full-lake survey.
Residents are encouraged to report SAV observations that they feel are of concern due to density and location. Reports can be made to SMLA at sav@smlassociation.org or TLAC at tlac@sml.us.com.
To make a report, be prepared to provide a detailed description of the location including latitude/longitude as well as contact information for follow-up. A description along with a sample of the vegetation is extremely helpful. If a sample cannot be provided a photo can also be helpful.