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Lake Management for Conservation Commissions and Lake Associations. Ken Wagner, PhD, CLM, Water Resource Services. Part I – Lake Management and the Wetlands Protection Act. Reasons for lake management Algae control Rooted plant control Sedimentation mitigation Fishing enhancement
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Lake Management for Conservation Commissions and Lake Associations Ken Wagner, PhD, CLM, Water Resource Services
Part I – Lake Management and the Wetlands Protection Act Reasons for lake management • Algae control • Rooted plant control • Sedimentation mitigation • Fishing enhancement • Other interests • Nuisance animals • Rare species • Birding • Access
Part I – Lake Management and the Wetlands Protection Act Algae control • Most algae grow in proportion to available nutrients and light • Focus on nutrient control, esp P, for best results • Watershed management • Internal load reduction • Dredging • Inactivation • Oxygenation • Drawdown
Part I – Lake Management and the Wetlands Protection Act From Watson et al. 1997 L&O 42(3): 487-495 Relationships of TP to Chl to cyanobacteria: More P leads to more algae and more algae leads to more cyanobacteria. Other algae can bloom too, but probability of cyano blooms rises with P. (10 ug/L) (100 ug/L)
Part I – Lake Management and the Wetlands Protection Act Algae control • Where nutrient control is not feasible, control should focus on prevention of blooms, not removal of existing blooms • Algaecides • Circulation • Flushing • Sonication • Dyes • Biomanipulation • Bacterial additives • Mechanical removal?
Part I – Lake Management and the Wetlands Protection Act Rooted plant control • Choice of method highly dependent upon: • Species of plants to be controlled • Areal coverage • Density of coverage • Potential non-target impacts
Part I – Lake Management and the Wetlands Protection Act Rooted plant control • Watershed management will not solve the problem • Water quality management unlikely to solve the problem • Often need a combination of techniques • Often need repeat application • Quick action upon discovery of an invasion is essential if there is to be any chance of eradication
Part I – Lake Management and the Wetlands Protection Act Rooted plant control • Physical: drawdown, harvesting, dredging, benthic barriers • Chemical: herbicides, dyes • Biological: herbivores, pathogens, competitors • Each has pros and cons, each has optimal conditions for application (see Lake Management in MA)
Part I – Lake Management and the Wetlands Protection Act Sediment mitigation • Four choices: live with it, dredge it, decompose organic matter, raise water level • Dredging is the most restorative choice, but is very expensive and requires considerable information to plan and permit; sediment quality and quantity must be thoroughly evaluated • Decomposing organic sediments is possible with adequate oxygen and appropriate microbes; an industry has arisen around this approach, but little scientific evidence of successes • Raising the water level is not practical in many cases
Part I – Lake Management and the Wetlands Protection Act Fishing enhancement • Boils down to habitat and stocking; both have a role • Habitat will determine long term fishery conditions; temperature, oxygen, pH and trophic status all matter • Stocking provides short term enhancement and may provide longer term benefits if habitat is suitable • Regulation may also be important; overfishing can be a real force • State agencies have interest and expertise in habitat, but focus mainly on stocking and regulation
Part I – Lake Management and the Wetlands Protection Act Other interests • Nuisance animals – beavers, geese, leeches, swimmer’s itch – need to view control in context of habitat and ecosystem function • Rare species – protected by law, promoting them is desirable, but requires a plan and permission • Birding – popular passtime, many water dependent species, not always compatible with other uses – need to consider habitat needs, spatial and temporal separation from potentially conflicting uses • Access – public vs. private lakes pose major issues with regard to responsibility, funding, downstream impacts, individual vs. societal rights – room for a lot of debate, a very sensitive area with many groups
Part I – Lake Management and the Wetlands Protection Act • How the Wetlands Protection Act (WPA) relates to lakes • History of WPA • Act and subsequent regulations (1983) and revisions (1987, 1997) to protect wetlands, an imperiled set of habitats • BVW, LSF, Bank, VP, LUW: lakes as wetlands • Lakes as embodiment of range of wetland habitats • Conundrum of active management of lakes • Limited projects10.53 (4) • Land Under Water 10.56 • Performance standards 10.60
Part I – Lake Management and the Wetlands Protection Act • How the Wetlands Protection Act (WPA) relates to lakes • Seven original “interests” of the WPA • Protection of public and private water supply • Protection of ground water supply • Flood control • Storm damage prevention • Prevention of pollution • Protection of land containing shellfish • Protection of fisheries
Part I – Lake Management and the Wetlands Protection Act • How the Wetlands Protection Act (WPA) relates to lakes • Regulatory adjustments • Addition of 8th “interest”: habitat – problem issue for any management program • Policies and guidance over the years to address specific issues • GEIR for Eutrophication and Aquatic Plant Management in Massachusetts • Not the last word; meant to be updated • Provides guidance, not regulation or rules • Problem situations accumulating • No regulatory provision for revision
Part I – Lake Management and the Wetlands Protection Act • Related legislation and regulation • MA Endangered Species Act and NHESP • Riverways Act – streams and rivers, not lakes • MA DEP Storm Water Policy • Chapter 91: Waterways License re: Great Ponds • Federal Clean Water Act, Sec 401 and 404 • Federal Clean Water Act, Sec 305b and 303d • Federal Clean Water Act, Sec 314 and 319 • Federal Insecticide Rodenticide and Fungicide Act • National Pollutant Discharge Elimination System • Invasive species transport bans • Instream flow initiatives
Part I – Lake Management and the Wetlands Protection Act • Related issues • Double jeopardy from overlapping regulation • Lack of a mandate to control invasive species • Focus on endangered species instead of communities • Little inclusion of safety, economic limits or recreation in WPA – but there is some, and room to interpret • Lack of process for rapid response planning and permitting • Ability to monitor to predict problems and be proactive
Part I – Lake Management and the Wetlands Protection Act • Bottom Line: • There is a lot for a Conservation Commissioner or a Lake Association to know when dealing with lakes • Lake projects have potentially more environmental regulation than development projects • Like buildings, lakes require maintenance to remain in acceptable condition; no action is not preservation • Prevention is much preferred over rehabilitation, but can’t always be arranged • The WPA and related regulations provide a framework for lake management, but also have gaps, contradictions and confusing aspects that make the job of a Commissioner more difficult
Part I – Lake Management and the Wetlands Protection Act Reasonable expectations from applicants • Properly characterize the resources involved • Clearly identify the problem(s) • Demonstrate consideration of options • Provide an evaluation of non-target impacts • Show how the interests of the WPA are affected • Provide an appropriate monitoring program • List follow up and contingency actions • Explain how other permitting processes apply • Identify who will be responsible for what actions
Part I – Lake Management and the Wetlands Protection Act Reasonable expectations from conservation commissioners • Be familiar with available guidance on lake management (GEIR, other resources) • Do not base feasibility or applicability conclusions on any one example; consider range of possible outcomes, avoid secondary sources, personal opinions, and unsubstantiated claims • Keep an open mind; do not limit options due to personal prejudices for or against any technique • Know where you can compromise and where you have to hold the line on WPA provisions – not easy to do, but work at it • Help craft reasonable monitoring programs, not extorted research projects • Do not overstep jurisdictional bounds; avoid requiring actions not related to the problem • Seek to be part of a solution to any problem; commissioners should be more than umpires
Lessons from Experience • There is no one size fits all solution; the specific conditions in each case dictate the most viable course of action • There are likely multiple possible solutions, and multiple techniques are likely to be involved over time • Comparisons between lake projects must be tempered by lake-specific situations; because something did or did not work at Lake A is not grounds for a strong conclusion at Lake B without careful analysis • Questions from conservation commissions should help shape the project within the context of the WPA; foster adaptive management over time
I’m gonna need another one of these Questions?
Part II – Common Western Massachusetts Plant Management Approaches • Water quality tends to be acceptable; more problems with rooted plants, partly due to higher water clarity • Drawdown practiced where outlet control over water level exists and permits can be obtained • Herbicides tend to be applied where problem is serious enough to warrant major biomass reduction • Mechanical harvesting was popular when county operated machines, still a viable method of maintaining selected areas for recreation • Manual harvesting difficult on very big scale, but proven useful for limited area lakes; sometimes aided by suction harvesting • Benthic barriers useful for localized near-complete control • Dredging very desirable in many cases, but too expensive and extra depth not essential • Limited biomanipulation; more experimental, grass carp not allowed
Drawdown • Potential for control of nuisance aquatic plants by drawdown • Key attributes of success: water level control, dewatering, weather, physical disruption • Primary impediments: impacts to non-target species, flooding and refill issues
Drawdown Targets • Vegetative propagators vs. seed producers • Possible control of milfoil, fanwort, coontail, water lilies, watershield • No adverse effect on naiad, most pondweeds, water chestnut, Chara and Nitella, except by long-term sediment changes
Drawdown Issues • Importance of physical disruption of overwintering plant form • 30 days of dryness and/or freezing temp. • Ripping plants up with early refill possible • Variability in response, need for planning for annual drawdown
Drawdown Issues • Impacts on wells • Impacts to other aquatic plants • Impacts to contiguous wetlands • Impacts to invertebrates • Impacts to reptiles and amphibians • Impacts to fish • Impacts to birds • Impacts to furbearers
Drawdown Experience • Weather dependent technique; have to consider longer term conditions and expect year to year variation – evaluation should span 3-5 years! • Can be very effective against milfoil, fanwort, any submergent perennial if killing conditions achieved • Not directly effective against emergents (tend to be dormant) or annual species (come back from seed) • Makes substrate more coarse (more rock, gravel, coarse sand) over time with enough slope; provides indirect control through substrate limitation • Rare to be able to draw down to level that prevents any nuisances by target species • Deeper drawdowns present spring refill issues, possible ecological impacts
Herbicides • 9 active ingredients available: • Copper- mostly for algae, limited vascular plant applications • Diquat – contact herbicide, spot treatments • Endothall– contact herbicide, spot treatments • 2,4-D – older systemic; limits on use, but potentially effective on some species where other herbicides are not • Glyphosate – systemic, mainly for emergent growths • Imazopyr/Imazomox – systemic, mainly for emergent plants • Fluridone – systemic, slow acting, mostly whole lake or sequestered applications, species targeting by dose • Triclopyr – systemic, fast acting, spot treatments possible, effective on milfoil but not pondweed species • Flumioxazin – contact herbicide, spot treatments possible, effective on wide range of invasive and nuisance species
Herbicides • With very different active ingredients, labels, and application conditions, blanket statements about herbicides are inappropriate • Herbicide costs vary substantially; cost per treatment and number of treatments needed over 20 years should be considered • It is reasonable to be concerned over possible non-target impacts, including human health, but direct impacts are very, very rare; experience shows that risks are small • Very few techniques can get a plant infestation under control quickly and at reasonable cost the way herbicides can, when properly chosen and applied
Herbicide Treatments • Contact herbicides kill only the part of the plant with which they come in contact, but tend to act fast • Systemic herbicides are taken up and kill whole plant at sufficient dose, but tend to act more slowly
Herbicide Treatments • Effectiveness varies with target species and ambient conditions • Selectivity can be achieved by timing of treatment, location of treatment, and dose for some herbicides • Longevity limited for ideal growing situations, but can be enhanced by encouraging desired species
Herbicide Treatments • Direct impacts to non-target fauna are very limited when label restrictions are followed • Indirect impacts are possible as habitat is altered by change in plant density or relative abundance
Herbicide Treatment Issues • Long-term control • Low dose “success/risk” • Water supply restrictions • Minimal issues for fish, shellfish • No issues for flood or storm control • Legal debate over pollution applicability • Certainly changes habitat
Herbicide Experience • Diquat is most popular contact herbicide; used to clear swimming areas, control regrowth after some whole lake systemic treatments • Glyphosate and Imazopyr/Imazomox most often used on floating or emergent plants, such as water lilies, cattails, phragmites • Fluridone used most on Eurasian milfoil and fanwort, often whole lake treatment, but advanced in pellet formulas aids spot treatment • Triclopyr newer, gaining acceptance, works on certain plants (including milfoil) relatively quickly and thoroughly • Flumioxazin also newer, gaining acceptance, works fast in smaller areas, affects wide range of nuisance species • 1-4 years of control is to be expected; more only with follow up actions – for best results, let professionals guide herbicide use planning
Rotovation • Hydroraking Harvesting • Hand pulling • Rakes and cutters • Mechanical harvesting
Harvesting- Hand Pulling • Effective for limited area infestations • Can be very selective • Best with sparse growth of invasive species • Need to control fragments • Possible high labor cost, repetition expected • Suction systems may help with denser areas
Harvesting- Rakes and Cutters • Can clear small areas • Moderately selective • Fragments collection necessary for some species • Effective for seed producers if timed correctly • Labor cost usually moderate, repetition expected
Harvesting - Mechanical Harvesting • Can clear larger areas • Best results if biomass collected and removed • Analogous to mowing the lawn for many species • Limited but possible selectivity over time • Some evidence of carry-over effect • Capital or contract cost high, repetition expected
Harvesting– Rotovation • Can clear moderate sized areas • Disrupts plants at roots, but rarely includes collection of biomass • Non-selective • Highly variable longevity • “Messy” operation • Capital or contract costs high, repetition not as likely as for other techniques
Harvesting – Hydroraking • Can clear moderate areas • Removes plants at roots with some sediment • Non-selective • Variable longevity, but successful for certain species • High capital or contract cost, repetition not as likely as for other options
Harvesting Experience • Rotivation not applied much in New England • Hydroraking mostly used to control water lilies, remove floating islands and debris, less common in Berkshires • Mechanical harvesting less common now (less convenient, higher cost), but works well as a maintenance technique with adequate equipment – WPA issues limited by affected area • Manual methods gaining momentum; both professional and volunteer efforts have demonstrated success – longer term success remains to be documented, but trends are encouraging – few WPA issues
One more and this will all make sense… Questions?
Part III: Keys to Successful Lake Management Ken Wagner, Ph.D., CLMWater Resources ManagerWater Resource Services, Inc.kjwagner@charter.net
Key Elements:Set realistic goalsInvolve all relevant partiesApply sound sciencePrevention with any rehabilitationOrganize, prepare, anticipateFocus and persevereAdequately fund actionsPublicize and recognizeMonitor and follow up…true, but boring…
Summary in One Word: Openness • Open process – inclusive, fair, comprehensive • Open minds – evaluate without prejudice • Open lake – private property vs. public opportunity • Open checkbook – you get what you pay for • Open ended management – no clear endpoint, follow-up needed
Open Process • Solicit input from all interested parties: lake users, potential lake users, property owners, those with political or regulatory jurisdiction, those holding the purse strings
Open Process • Try to accommodate reasonable uses Ballroom catfish dancing – one esoteric pursuit Recognize potential conflicts Incredible fishing?
Open Process • Set realistic goals, arrived at as a group Most lakes can support multiple uses, but recognize the limits
Open Process • Seek true conflict resolution, not to win a power struggle I’ll show you how we resolve conflicts in Chicago One ring to rule them all…