Some say there hasn’t been enough opportunity for public comment. Some say the current method of handling in-lake maintenance on Chautauqua Lake is fine and a plan isn’t needed. Others bristle at the plan’s inclusion of herbicides alongside biologic and mechanical methods of controlling invasive weeds in the lake.

Reasons for towns, villages, Chautauqua County and the Chautauqua Lake Watershed and Management Alliance not to adopt the N.C. State plan have popped up in government meetings since December. What hasn’t been discussed much publicly is what’s actually in the plan.

NC State’s Aquatic Plant Management Program was contracted by the Chautauqua Lake Partnership, with funding appropriated by the Chautauqua Lake Watershed and Management Alliance, after CLP officials said discussions with the state DEC and others showed a need to clarify the goals of herbicide applications for Chautauqua Lake and to articulate a long range plan to achieve those goals.

North Carolina State University’s Aquatic Plant Management Program has completed full lake surveys of Chautauqua Lake each year since 2020 that include collecting and analyze hydroacoustic and point intercept data annually at up to 1,000 sites throughout the lake and documenting the presence and extent of aquatic plant species during the fall and spring seasons.

A Chautauqua Lake Association harvester is pictured in Chautauqua Lake. Mechanical harvesting of lake weeds is included in a plan by the North Carolina State University Aquatic Plant Management Program for Chautauqua Lake - though the plan calls for changes to the way mechanical harvesting is done and when it is done on Chautauqua Lake. P-J file photo

NSCU’S GOALS

NC State’s Aquatic Plant Management Program officials propose a staged plan that deals with the entire lake rather than the 2017 Chautauqua Lake Macrophyte Management Strategy’s approach that divides the lake into subsections based off of shoreline use and the need to balance human interaction with environmental considerations. North Carolina State University officials said the approach is good for small areas but shifts lake management strategies away from a focus on plant ecology to meet the county’s goals in managing vegetation in the lake.

Goals include reducing the nuisance level of Eurasian watermilfoil and curly-leaf pondweed, identifying control measures for starry stonewort, encouraging native lake vegetation species throughout the lake but in particular in the south basin, limiting continued spread of non-native species in the Chautauqua Lake watershed, shifting the lake’s algal community away from cyanobacterial dominance and supporting the local fishery – in particular the established game fish population.

MANAGING THE PLAN

The first thing North Carolina State University officials recommend is coordinating management decisions through a central entity, recommending a lake manager to coordinate and track work on the lake. That work would include coordinating long-term data collection and interpretation, getting information out to the public and coming up with science-based strategies. The manager could also work with local and state agencies on permits and monitor all vegetation management throughout the growing season while working with an executive board that represents the diverse interests of lake organizations. Annual reviews of long-term aquatic plant management is recommended, with that review taking place in the winter so changes can be made before the next growing season.

SOLitude Lake Management employees are pictured in 2017 applying herbicides to Chautauqua Lake. Herbicides are part of a lake management strategy recommended by North Carolina State University’s Aquatic Plant Program - though the plan has thus far only been approved by the town of Ellery. P-J file photo

The five-year plan is grouped into three tiers of work.

Tier 1 would focus on long-term management zones where there is consistent Eurasian watermilfoil and curly leaf pondweed growth as well as any growth within 100 feet of high-use areas. Those areas would be managed each year. Tier 1 also includes habitat protection zones where there would be limited, low-impact management in areas of Chautauqua Lake where rare, threatened or endangered aquatic plant species are found according to fall surveys, high aquatic plant diversity areas that are documented each year during a fall survey and sensitive fish spawning sites.

Tier 2 would be classified as short-term management zones where there is new moderate or dense growth taking place outside of Tier 1 areas. Tier 2 may require management for less than four consecutive years.

Tier 3 would be a maintenance management area outside of Tiers 1 or 2 where spot treatments are done as needed. That would also include previously managed areas prior to the development of a long-term plan.

CHANGES TO MANAGEMENT

Management of curly-leaf pondweed would begin in March with management zone confirmation, followed by application of herbicides and/or mechanical harvesting in April and May. May and June would be a post-treatment assessment and survey period with no mechanical harvesting. Then, turion bank sampling would take place in September.

Eurasian watermilfoil work would begin in June with management zone confirmation followed by use of herbicides and mechanical harvesting in July. Post-treatment assessment and surveys would then begin in August.

Algae management should focus on watershed-level or lakewide initiatives that disrupt the causes of algal blooms. N.C. State officials say things like algaecides, aeration and nutrient sequestration may not resolve long-term algae trends in the lake but can provide temporary relief in some areas.

“This option may be crucial to the mitigation of algal blooms that have the ability to interfere with lake uses such as swimming, boating and fishing and post a threat to human health,” the plan states.

As of 2023, starry stonewort has been found in a small portion of Chautauqua Lake’s littoral zone, but is present in multiple sites within the main body of the lake. Researchers say management of starry stonewort should begin as soon as possible before the species continues to move into more of the lake.

Guidelines For Harvesting, Herbicides

North Carolina State officials aren’t proposing abandoning either mechanical harvesting or herbicides. Instead, they call for a standardized approach to both methods of controlling invasive plants in Chautauqua Lake. Harvesting can provide immediate relief to plant growth and “can be a valuable tool for maintaining open surface water,” the plan states. Small-scale or manual harvesting should happen in near-shore management areas while ensuring that at least 2 feet of submerged aquatic vegetation biomass remains in the main lake areas or 1 foot in high-use areas. It is recommended to collect floating debris and return harvested fish or other bycatch to the lake when possible. High priority areas for mechanical harvesting would be access sites, highly used areas near parks, hotels and marinas and early season curly leaf pondweed beds while moderate priority would be given to areas of the lake where ater depth is between 5 and 10 feet and in recreational boating zones. Low priority for mechanical harvesting would be given to areas of the lake where water depth is greater than 10 feet and restricted zones would be habitat protection zones and areas within 50 feet of treatment zones so targeted species aren’t reintroduced from fragmentation drift.

Herbicide use should be targeted early in the plant’s life cycle to limit reproduction and nutrient releases while a streamlined permitting process with municipalities should be a priority so treatment can take place earlier.

The plans also calls for monitoring of weevils, with more weevils added in areas where densities have fallen.