DEP 332-693 Dudley Pond
2011 End of Season Report to the Wayland Conservation Commission
6 lb. 12 oz. Largemouth Bass caught on Dudley Pond September 13, 2011 Caught & released by Wayland resident Al McEvoy
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SUMMARY The 2011 hand-pulling and spot treatment program was highly successful. No milfoil was detected at end-of-season. Accomplishments: Hand-pulling: Kept Eurasian Water Milfoil under control thru o 2011 274 diver/snorkeler hours of hand pulling and survey 10,485 plants removed by the roots. o 2010 287 diver/snorkeler hours of hand-pulling, 6145 plants removed by the roots.
Funding: Continued the principal of 25% shared funding with the DPA whose members care deeply about Dudley Pond and who directly enjoy its benefits. Minimized chemical treatment through continued aggressive hand-pulling. Continued consensus for limiting herbicide with goals and programs to minimize its use. Completed annual testing for detection of both fluridone and triclopyr in Happy Hollow wells #1 and #2.
Yearend status: No milfoil found in underwater inspections. Observations: More regrowth in areas of lighter 2010 triclopyr use Fewer large old plants, smaller plants Very few plants at the start of the season Regrowth often associated with areas near storm drains. Related Activities: Dudley Pond – only one of three operational in 2011, repairs attempted, manufacturer unresponsive, repairs will be re-attempted after ice-in. Water clarity remained significantly better that expected during the year, although 6-8 weeks after spot treatment, clarity diminished making it difficult to continue hand-pulling. WSWQC is developing proposed septic and landscaping regulations which would require additional measures for areas in close proximity to water bodies.
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2012 Dudley Pond Plans:
SWQC has budged for, and plans to continue aggressive hand-pulling at the same level or higher than 2011 – and we are looking for means to extend our pulling season and make divers more productive. Herbicide use is not planned, but may be necessary in mid to late season
SWQC will continue its systematic sampling program for phosphorus, chlorophyll-a together with temperature, Secchi-depth, and dissolved oxygen – in order to position the pond on the Carlson Trophic Index axes.
SWCQ will continue its cooperative effort with the Board of Health to sample for e-coli contamination.
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2011 HAND-PULLING Milfoil appeared first near-shore, in shallower warmer areas. Most areas spot-treated with triclopyr in 2010 showed reduced counts in 2010 – although Lakeshore Drive between Mansion Beach and Simpson road was under-treated and had significant numbers of plants. Areas with lush plant growth were associated with areas close to stormwater outfalls. As in prior years, divers would update a detailed web form, and were paid based on their posted updates. Notes were kept on ‘seeing’ conditions, water temperature, and comments on plants. (See Appendix A1) Ted Fiust and Allison LaClaire were our principal divers. Both are familiar with and lived on Dudley Pond during the 2010-2011 seasons. Volunteer snorkeler Bob Smith helped out with the Mansion Beach area during the season. Total weed management cost was $10,760.
2011 hand-pulling began May 5th, and continued late into October until it became too cold to pull.
Figure 1 - Allison LaClaire & Ted Fiust
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2011 HAND-PULLING RECAP 10485 plants were removed by the roots. Two principal divers and three other divers and snorkelers logged 274 hours under water. To water users on the surface, there were no impediments to use – and no apparent milfoil.
Cost per plant: PLANTS 2011
10,485
274 $10,360 $1.01
Diver hours Cost per plant
287.2 $11,488.00 $1.87
Diver hours cost per plant
358 $ 14,320.00 $0.79
Diver hours cost per plant
PLANTS 2010
6,145
PLANTS 2009
18,237
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2011 PLANT LOCATIONS – High count areas highlighted in yellow
For reference: 2010 Triclopyr spot treatment areas
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2011 END OF SEASON SURVEY Our active management season late into the year – because we continued to find scattered plants to pull. The last two diver hours were booked October 22nd and no plants were found on that day. We did not complete an end of season survey because we were still pulling, however the consensus of the divers was that we’d pulled everything we could find.
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2011 E-COLI TESTING After a leaking septic system was noted near the pond in 2001, in cooperation with the Board of Health, SWQC organized periodic testing for e-coli. Samples were collected and analyzed per state protocols for beaches. At two points in 2011 the state limits were exceeded at Mansion Beach, and the beach was closed by the Health Department, based on state beach standards.
e-coli sampling points:
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2011 WATER QUALITY TESTING – see APPENDIX C The SWQC did three rounds of water quality sampling – where samples were taken at 3 points. Samples were taken in April, September, and November.
Using a Secchi disk and YSI meter, barometric pressure, ph, ORP, Dissolved Oxygen, Temperature were taken at three depths per point. Water samples were analyzed by an analytical lab for total P, soluble P, Ammonia, Nitrate/Nitrite, Nitrogen, and Chlorophyll a. Using the Carlson Trophic index, Dudley Pond has been on the margin between mesotrophic and eutrophic since 1978,
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2011 East Dudley Septic Study – see APPENDIX B In 2010-2011 the WSWQC prepared a study of the septic system on the East side of Dudley Pond. The memorandum below and full report was delivered to the Board of Health, Conservation Commission, Selectmen, Planning Board, and the Wastewater Management District Commission. Presentations were made on the report to all groups. The memorandum: This report summarizes a study of phosphorus discharges associated with septic systems located on properties abutting the eastern shore of Dudley Pond. The objective of this study was to begin the process of minimizing the negative impact of septic systems on the water quality of Dudley Pond. This memo contains a summary, recommendations, background information, study methods, results and a discussion of the results as well as an appendix containing data gathered during the study. Summary
Dudley Pond is a Massachusetts Category 5 (worst) impaired water body, contains excessive concentrations of weed fertilizing nutrients (phosphorus) and costs the Town of Wayland (TOW) and the Dudley Pond Association (DPA) many thousands of dollars annually for weed maintenance to keep the Pond usable for recreation, free of fish kills and noxious odors.
Phosphorus, associated primarily with surface water runoff and ground water is generally accepted as the limiting nutrient for weed growth in fresh waters.
The major sources of phosphorus entering the Pond are thought to be primarily from septic systems and secondarily from surface water runoff.
All of Wayland is serviced by septic systems, 106 of which are located on small lots abutting Dudley Pond and are very close to the Pond.
The ground water elevation on the east side of the Pond is higher than the Pond water elevation, therefore any effluents from septic tanks on the east side of the Pond that intersect the ground water table most likely flow into the Pond.
The findings from this study are: o 50 septic systems are located on the east side of Dudley Pond, with ages ranging from one to sixty seven years old, with an average age of 24 years for the systems where BOH records exist. It is generally accepted that septic systems have finite life of 20 – 30 years. o
The types, age and location of 15 of these septic systems are unknown because no drawings exist in the TOW Board of Health (BOH) files.
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103 +/- (college students away) residents live in houses abutting the Pond and are served by septic systems in the east Dudley Pond watershed, the effluents of which collectively contain approximately 155 pounds per year of phosphorus.
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8 of these septic systems have had a Massachusetts Title 5 inspection.
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Annual water usage of these 50 properties ranges from 50 – 14,900 cubic feet per year (374 – 111,452 gallons per year) with the average household usage 5,400 cubic feet per -10-
year (40,600 gallons per year) and the average per-capita usage of approximately 54 gallons per person per day. o
Because of the small lot size and high ground water elevation in this area many of the septic systems are located close to Dudley Pond and the elevations of the septic system leach areas are close to the elevation of the ground water, which increases the probability of contaminating ground water and subsequently the Pond.
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The soils in the Dudley Pond east watershed are predominantly sandy, are very permeable and do not readily adsorb and retain phosphorus compounds.
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Of the 50 septic systems 7 systems do not have records of being pumped at all. The average time elapsed since the last pumping for the systems that had records was 4 years. There are 2 “tight” tanks amongst the 50 septic systems, both of these properties appear to have used significantly more water than their tanks can hold.
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One septic system connected to a rental property with three inhabitants failed during the summer of 2010. The TOW BOH is pursuing the situation.
Recommendations The following are recommendations resulting from the study: 1. As stated in Wayland’s Master Plan, “To address this concern [Dudley Pond] a more proactive approach toward minimizing septic system problems on private lots is recommended”. 2. This study should be reviewed with the TOW BoH, DPA, Conservation Commission, Planning Board, and the Board of Selectmen (BoS). 3. For the properties where no septic system drawings and/or where pumping records are old or do not exist (15 – 20 systems) it is recommended that the BOH require that a Title 5 equivalent inspection be completed as soon as possible and a Title 5 equivalent inspection timetable be established for the balance of the systems. 4. Further Surface Water Quality Committee (SWQC) reviews need to be undertaken for septic systems with high scores resulting from this study and for systems where information such as plot plans, construction dates, pumping records are missing from BOH files. 5.
Inconsistencies between water use records and tight tank pumping records need to be resolved by BOH/SWQC.
6.
It is recommended that the TOW adopt a by-law that requires septic systems within the Dudley Pond watershed to be pumped at a minimum of every 3 years.
7. The SWQC should work with the BOH to obtain funding from Massachusetts Water Pollution Abatement Trust for septic system tracking software and to pay municipal employees to gather and track septic system data. For more information on this visit: http://www.wickedlocal.com/mendon/news/x1799252093/Mendon-may-join-septic-system-loanprogram 8. The SWQC should continue to seek grants to in order to complete a federal and state-mandated Total Maximum Daily Load (TMDL) for phosphorus study, the objective of which is to determine the maximum amount of phosphorus that can be discharged to Dudley Pond under the -11-
State’s water quality standards and develop a plan to meet that goal. Such a TMDL would be required to form a rational basis for TOW Dudley Pond watershed by-laws. 9. A public education program regarding nutrient management should be continued in the Dudley Pond watershed, with the highest priority being the eastern part of the Dudley Pond watershed. 10. An additional study of septic systems, ground water elevations and ground water/soil phosphorus concentrations should be undertaken on the properties between Dudley Pond and Route 27 by the SWQC. This study may be later extended to the entire Dudley Pond watershed, the Lake Cochituate and Sudbury River watersheds in Wayland, and the Heard Pond watershed. 11. The SWQC should prepare draft by-laws for Dudley Pond and other Wayland watersheds, modeled after other Massachusetts communities’ nutrient management by-laws, for consideration by the Board of Health, Conservation Commission, Planning Board, Board of Selectmen, and interested watershed associations. 12. The TOW should commission a study of the following alternatives: a) A sewer system and community advanced (nutrient removal) treatment system for the properties in the east Dudley Pond watershed, at a location to be determined. b) A sewer system for the east Dudley Pond watershed that connects with the MWRA pump station located at the intersection of the Mass Pike and Route 27. Background This study was undertaken by the Wayland Surface Water Quality Committee (SWQC) because:
The State of Massachusetts has designated Dudley Pond is a Category 5 impaired water body due to organic enrichment, low dissolved oxygen, turbidity and exotic species (Eurasian Milfoil). Range of categories 1 – 5, with 5 being the worst - Table 1 below.
The high nutrient concentrations in Dudley Pond are the ‘root cause’ of excessive growth of aquatic weeds and algae. The Town of Wayland (TOW) and the Dudley Pond Association (DPA) have spent significant amounts of money for weed management in Dudley Pond over the past 30 years.
The aquatic weed that is the major symptom of the problem in Dudley Pond is Eurasian Milfoil. Fortunately, to date, there has not been a documented blue-green algae bloom in Dudley Pond, despite the fact that there was a blue-green algae bloom “epidemic” in the northeast during the summer of 2009. The reasons for the epidemic are not known.
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2011 PROBLEMS, HANDICAPS, & ISSUES
Temperature: Water temperature limits the time a diver can be submerged, the difficulty of manipulation and pulling, and the ability to attract divers at all. Milfoil grows in spring and fall when water temperatures make it impractical to dive in a wet suit. WSWQC may consider acquiring one or two ‘dry suits’ which would extend the hand-pulling season.
Equipment reliability: A power regulator failed on one circulator and on another wires were chewed or cut. Circulator use will be phased out.
Diver Productivity: Cost per plant harvested was up because the plants were fewer and farther apart – and because water clarity limited us at season end.
Wayland Surface Water Quality Committee
Dudley Pond – DEP 332-698 2011 End of Season Report
2011 EFFECTIVENESS, OBSERVATIONS, LESSONS, CONCLUSIONS Neither Fluridone nor triclopyr were detected in Happy Hollow water sample. In 2011 we again took samples of water from the Happy Hollow wells, and sent them to SePRO for testing. The wells were off-line in spring and summer, so the water sample was taken in the fall No detectible concentration of fluridone nor triclopyr was found. We will continue this testing in 2012. Submersible ‘scooters’ In 2009 we tested two electric-powered, recreational scooters. In 201011 these were helpful during the end of season surveying, and also allowed divers to cover larger areas of more widely distributed plants. Herbicide use possible in 2012 We expect regrowth in 2012 and believe that hand-pulling alone will be sufficient. A mid to late summer spot herbicide treatment may be necessary. Our long term goal is to continue to reduce the viable root mass through hand-pulling and spot treatment when and where necessary. We have made good progress away from a boom-bust cycle toward year to year management and herbicide minimization.
Wayland Surface Water Quality Committee
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Dudley Pond – DEP 332-698 2011 End of Season Report
2011 GOOD WATER CLARITY (SECCHI DEPTH) Water was reasonably clear in 2011 but not as clear as 2009. Jack Peters, a DPA member, took Secchi depth (the depth at which the pattern on a painted 9� disk disappears) and water temperature readings. An increase in water clarity over the summer may have allowed more light to reach lower depths stimulating plant growth in deeper areas. Clarity is normally higher when water is colder at the start and end of the season when there is less algae in the water column. Water clarity is claimed to be an effect of water circulators, but WSWQC has no evidence to suggest that is the case in Dudley Pond.
2010 Secchi depth (ft) 25.00 20.00 15.00 10.00
depth
5.00 0.00 3/16/10 4/16/10 5/16/10 6/16/10 7/16/10 8/16/10 9/16/10 10/16/10 11/16/10
Wayland Surface Water Quality Committee
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Dudley Pond – DEP 332-698 2011 End of Season Report
2012 SEASON PLANS Well Sampling: We will continue annual spring tests of water from the Happy Hollow wells for fluridone. Samples will be analyzed by SePRO, and copies of test reports will be provided to the Conservation Commission, the DPW, and Board of Health Hand-pulling: Hand-pulling will continue at the same level as in 2011. We don’t know what to expect at the start of the season. We are looking for ways to make our divers more efficient and for them to work earlier and later in the season when the water is too cold for wet suits. We may employ a part time aid to make and set markers. Spot treatment: We will investigate identified troublesome areas for potential spot treatment, but hope to avoid herbicides in 2011. Should we decide that spot treatment is required, we will notify the Conservation Administrator as required by our Order of Conditions. Water Quality Testing: We will continue a periodic water quality sampling and testing plans begun in Dudley Pond in 2011. Research & actions to reduce nutrients Suppressing milfoil with hand-pulling or herbicides is not the same as reducing the high nutrient levels that support milfoil growth. Dudley Pond is still a category 5 (most impaired) due to high nutrient levels. The WSWQC is participating in the Dudley Area Study Committee, and has developed a household-level model to identify likely high-nutrient contributions. WSWQC is also investigating improvements to Dudley Pond storm water management (notably ironenhanced sand filters).
2012 EXPECTED COSTS & FUNDING WSWQC has budgeted $16,000 for Dudley Pond hand-pulling during the 2012 season. We have a small contingency in our budget for a possible spot treatment. The Dudley Pond Association is expected to continue to provide a 25% match of monies spent suppressing milfoil in Dudley Pond, reducing actual Town expenses by approximately $4000.
Wayland Surface Water Quality Committee
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Dudley Pond – DEP 332-698 2011 End of Season Report
APPENDICES A1 A2
2011 Yearend DP Hand Pulling – Spreadsheet Details 2011 Yearend DP Invoice Recap – Cost summary
B1 B2 B3
East Dudley Septic Study Report East Dudley Septic Study Coverage Area Map East Dudley Septic Study Top-50 Recap
C
2011 DP Water Quality Sampling Reports
D
Trash Collection Recap
Wayland Surface Water Quality Committee
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