Harwich OKs alum treatment for Long PondHarwich’s conservation commission voted 3-1 to approve the proposed alum treatment of Long Pond, while Brewster Conservation Commission tabled a final decision until March 6.
The two groups held a joint meeting Tuesday night at Brewster Town Hall to discuss the chemical treatment plan that’s slated to get under way in May.
The Brewster board decided to wait to hear from the state because there is an endangered plant species growing on the pond shore and the Natural Heritage Endangered Species Program has to approve the project. The guidelines specify a 1,000-foot buffer around the species and the alum treatment will be as close as 850 feet to the shoreline, so the NHESP will have to grant a waiver.
Ken Wagner of ENSR, the environmental consulting firm that won the bid to install the controversial chemical treatment, said he had hoped to have that waiver in hand by the time of the meeting. The Brewster commission also wanted to wait to read a letter of comments from the state fisheries people. Wagner said he expects they’ll recommend the alum be injected deep below the surface and the treatment be done in the fall rather than the spring.
Wagner said the plant species would be unaffected by the alum treatment and the alum would pose negligible danger to spawning herring or other fish in the spring. The treatment will be rescheduled for a late-September application if the Brewster commission pushes a decision beyond March 6, as it would be too late to order the alum after that.
The concern is that Long Pond has become a sink for recycling phosphorus that has caused blooms of blue green algae and possibly fish kills. The 82,000 pounds of alum will bind with the phosphorus, forming a floc that will sink to the bottom and remain inert. Alum should work for 12 to 30 years, Wagner said, and coupled with watershed management of phosphorus inputs, indefinitely.
“The absence of watershed management means the system will go back to what it is now,” Wagner pointed out.
Aeration is also more expensive than the $417,848 the alum treatment will cost, and the two towns will pay only $60,000 of that. The state is providing $350,000 and Cape Cod Commission $10,000.
Watershed management would include controlling runoff from storm drains and possibly limiting fertilizer usage.
“During the treatment, a portion of the aluminum has the ability to be toxic to aquatic life,” Wagner conceded. “Fish and invertebrates could be harmed if they’re exposed to alum concentrations greater than 5 mg per liter at a ph outside the range of 6-8.”
“We will not let that happen,” Wagner said. “If we see fish swimming at the surface we will stop and adjust.” (Fish will still be edible after the treatment, Wagner assured the commissions.)
About 370 of the pond’s 743 acres will be treated, all in areas with a depth of 30 feet, with 25 acres a day being covered. At 30 feet deep, midges and some species of aquatic worms survive, and they will be impacted.
Michael Schreibman of the Harwich commission, who was the one member who voted against the plan, wondered if there was a sufficient insurance bond to cover any problems and if the removal of the phosphorus would cause the pond to become oligotrophic (short on nutrients).
“It’s a short term solution for a long term problem,” he said afterward.
Jason Ford, Larry Ballantine and Lindsay Strode voted in favor.
“Why is this on our plate now with elements of the state process hanging out there,” wondered Brewster chairman Steve McKenna.
“If there was not a protected species and redrawn state maps, we would not have it,” Wagner answered. “I did not anticipate having any involvement from them at all. It was a bit of a surprise. I expect to get a waiver.”
McKenna was also concerned that there is no watershed management plan on the table and that the fisheries seemed to favor a fall application.
Cynthia Boran, of the Brewster commission, wondered if the work would better be done in the fall.
The water temperature has to be above 40 degrees Wagner noted. He said the work could be done in September and October.
Karen Malkus, president of Friends of Long Pond, objects to the treatment plan. “I was surprised that (the Harwich commission) didn’t need to hear from the Natural Heritage group,” she said after the meeting.
Malkus believes not enough is known about the causes of the catfish kills or the pond’s chemistry as a whole.
“They only (sampled) four deep points on one day in one summer.”
She read a statement in opposition and presented the commissions a petition containing 211 signatures of people who oppose alum treatment.
“We’ve been told that only the worms in Long Pond’s deep zones will take a beating,” she noted, “(but) all members of the food chain are important to the larger food webs … destroying and damaging the invertebrates will be problematic for the future of Long Pond.”Timothy Doyle also spoke in opposition to alum.
“In my mind it’s a poison you’re putting in the pond and that’s the reason you have to put a neutralizer in with it. I think there are other ways to remedy the situation.”
Mike Ward told the commission that efforts should be made to manage the watershed system. “It was said it would take 37 years to see any results from management, well 37 years is nothing if you look down the road.”
Joyce Bearse told the commission she favors the treatment, as did Sue Phelan.
“We had sand we walked on and now we have a green slime,” Bearse said. “Right now we can’t see below 18 feet in Long Pond. We’re not going to be able to save it in 10 years.”
February 14, 2007
Discussions continue on Long Pond cleanup
By ROBIN LORD
BREWSTER - Members of the conservation commissions from Brewster and Harwich last night heard pleas on both sides of a plan to clean Long Pond of excess phosphorus.
The boards met at Brewster Town Hall, as both need to set an order of conditions for an upcoming treatment program.
No decisions were made last night, since the project still needs a waiver from the state Natural Heritage Endangered Species Program, said project manager Ken Wagner of ENSR, an environmental consulting firm.
Natural Heritage officials have found an endangered plant species living along the shores of the pond that are within 1,000 feet of where the alum will be applied, he said.
A petition with 211 signatures of people opposed to the alum treatment was handed in to the commissions. Many worry that the chemical, which binds with phosphorus and falls to the lake bottom in a gel form, will kill other pond life.
If applied incorrectly, alum has the potential to kill fish, as was the case in Hamblin Pond in Barnstable in 1995.
Robin Lord can be reached at firstname.lastname@example.org.
(Published: February 14, 2007)
Alum treatment plan advancesIt wasn’t exactly hold ’em and fold ’em time for the Long Pond alum treatment combatants, but it was the big sales pitch.Ken Wagner of ENSR, the firm under contract to apply aluminum sulfate and sodium aluminate as a phosphorus-control measure, presented a detailed synopsis of what, why, where and when of the proposed plan to 50-plus people Thursday at Harwich Town Hall. The next step is the official filing of the plan with the conservation commissions in Harwich and Brewster.“This is a meeting to lay all the cards on the table and to tell you the good and the bad,” said Wagner, who’s also president of the Lake Management Association. “I appreciate you do have some concerns but let’s not have any agendas. Let’s lay it out.”He was certainly enthusiastic about reducing fish kills and algae blooms by precipitating phosphorus out of the water column.“I believe in lake management. This is what I like to do for a living,” he declared. “I think you’ll get spectacular results. I think you’ll be pleased with it but you’ll have to commit to watershed management.”Members of the Friends of Long Pond, which opposes the treatment, were in the audience. They’d prefer aerating the lower depths rather than adding chemicals.“Windmills (for aeration) are a neat idea but there’s not that kind of money and there’s not that kind of time. To me it’s sad and frustrating,” Friends president Karen Malkus lamented afterward. “It could’ve been so much better. Maybe we could do something great for Long Pond that would be a model for other towns.”Chemicals are the “quick fix,” she believes.“It’s sort of a cynical choice,” she said. “It reminds me of Capt. Picard on Star Trek and the Borg – ‘resistance is futile.’”Or it’s not desirable.The Long Pond Watershed Association supports and originated the management plan.“In the past we’ve observed a lot of fish kills, mainly catfish. The past two years we’ve had high water levels and the extent of the fish kills has been much reduced,” noted association member Charles Parker. “I live in the west end of the pond where all of them end up. About three years ago there were quite a lot of dead catfish on shore.”There are no trout in Long Pond but there are bass, perch and herring in addition to the catfish. Phosphorus is a nutrient and when it builds up in the water it can cause an algae bloom that depletes the oxygen, on the bottom at first, where the catfish are.What is to be doneThe plan is to add 82,000 pounds of alum to the pond.The phosphorus in the sediments is bound by iron. Under anaerobic conditions in deep water, hydrogen sulfide is produced. The sulfide binds with the iron, releasing the phosphorus into the water. The alum and sodium aluminate will be sprayed from 25 nozzles on a barge into the deepest water (with a depth of 30 feet or more) covering about 370 of the pond’s 740 acres.The alum binds with the phosphorus, creating a “floc,” a sort of snow cloud of molecules, which sinks to the bottom, where it will remain inert. Alum lowers the water’s ph making it acidic, so the more basic aluminate is added to maintain the pond’s ph between 6.7 and 7.0. A decade ago fish kills were caused at Hamblin Pond in Barnstable when the ph got out of balance during treatment (up to 9.3).“That will not happen here. I do promise you that,” Wagner said.“If he’s going to do alum, he’ll probably do a good job,” Malkus conceded. “We’re so human centered. Can we jet ski? Can we use our boats? They say they’re putting it in deep water but they’re still putting it in the top.”Aquatic Control Technology will do the spraying in May, in 13- to 25-acre blocks, one per day, and should be done by early June.The original plan was to spend about $200,000, but over time the price has swelled to $417,848, with $350,000 provided by state grants, $60,000 by Harwich and Brewster and $10,000 from Cape Cod Commission.“This has been a 10-year project,” Brewster Town Administrator Charlie Sumner noted.Why not aeration?The three prime options to remove the phosphorus are dredging, which would cost $15 million, aeration in the depths to pump oxygen in, which would cost $1 million, and the alum treatment.“Most recreational lakes go with the alum; most water supply clients go for the aeration,” Wagner noted. “Aeration ecologically is a great idea.”Greater oxygen levels would also replace the blue green algae with green algae. But nonchemical options would take longer and require continuous treatment.“It’s a lower probability of success for more money,” Wagner said. “Alum also helps the oxygen at the pond bottom. At Hamblin Pond there was no oxygen at 20 feet. Now there’s oxygen down to 30 to 40 feet and I fully expect you to get the exact same benefit. They actually have trout fishing now.”The available phosphorus in the lake comes from precipitation (50 kilograms/yr); runoff (86-131 kg); seepage from groundwater (59 kg); waterfowl (6 kg); and the regeneration of the sediment (405-kg). The latter occurs almost exclusively in the summer, when low oxygen levels cause the iron to release it. That totals 652 kg a year. Levels below 461 kg would preclude algal blooms, so that’s the target.“The question is can we do it with watershed management and the answer is no,” Wagner said. “If we did nothing but manage the watershed, this lake is not going to get better in anyone’s lifetime.”Since 64 percent of the phosphorus is recycled, slashing that recycling by locking in the phosphorus seems the way to go. But that still leaves input from groundwater and runoff and if that isn’t controlled, phosphorus levels rebuild and alum treatment will be needed again in 10 to 20 years.“You can’t control the nitrogen (which comes from the air) so you need to reduce phosphorus low enough so it becomes the limiting element,” Wagner explained. “A high nitrogen/phosphorus ratio favors good (green) algae.”Malkus said she believes there hasn’t been sufficient study; only four sediment samples were taken in 2001, the species of blue green algae in the bloom was never identified, and impacts of nearby cranberry bogs haven’t been factored in.“It’s a question of a short term fix that doesn’t deal with the long term,” she said. “There are so many unanswered questions and to just say Ken Wagner is going to handle it. I know him – he’s not a bad guy, his intentions are good.”And the watershed control of lawn fertilizer runoff has been only a pipe dream.“The town has got to do watershed management, otherwise you’ll be back in the same place,” Wagner admitted.“It’s unfortunate that we’re not funded to do the next step,” Malkus noted, “and unless we support the watershed treatment we’re doomed. My major concern is that people do not know what it does to the ecosystem, just that it gets rid of all the bugs and worms people are glad to get rid of.”There were concerns about the alum’s toxicity to aquatic life.“The alum dose is not toxic below five milligrams a liter,” Wagner explained. “The treatment here will be below five milligrams. As it comes out of the barge it will be higher but as it mixes and flocs it will dilute.”“There are four ways to limit toxicity and we’re doing three of them,” Wagner said. “I don’t see a problem here with toxicity. If it gets out of the ph range we quit.”Very little, other than some worm species, lives on the bottom of Long Pond below 30 feet.“We’re doing it in 30 feet where there are no mollusks,” Wagner said. “Some of the floc may drift into shallow waters. The worms in the anoxic zone will take a beating but they’ll be back.”“They’ll come back, they say,” Malkus said later. “That means they die.”
Alum for Long Pond?A public hearing at Harwich Town Hall Thursday, Jan. 18, to address the remediation of phosphorus in Long Pond promises to be lively. It will mark the first time that all interested parties from both camps – those who support an aluminum sulfate treatment plan and those who don’t – will converge in one public place.The meeting, which starts at 7 p.m., is intended to provide background information and to answer questions from officials and citizens, says a statement issued by Charles Sumner, Brewster’s town administrator and a member of the Long Pond Working Group, which has participants from both municipalities. Ed Eichner, a water scientist with Cape Cod Commission, also is a member of the working group and supports alum treatment.Sumner’s announcement of the hearing does not refer to any specific treatment option, but since the towns have already signed a contract with a firm to apply aluminum sulfate – known as alum – the focus of discussion seems likely to be a debate of that proposed remediation. Sumner said the contract is subject to permitting approvals. (See related editorial comment, Page 14.)Brewster and Harwich share responsibility for the 740-acre pond. The application of alum has been a controversial and contentious issue since 2001, when ENSR International, an environmental consultancy firm, formally proposed the chemical treatment after conducting water and other studies. ENSR last month won the bid to apply the treatment at a cost of about $420,000 – almost exactly what the towns have to spend. Funding came from each town and from the county and state.Under the plan, alum would bind with phosphorus in the pond’s sediment and prevent it from entering the water column, where it becomes a nutrient for algal blooms. The blooms use up oxygen and can lead to fish kills. Phosphorus comes mainly from septic systems and run-off.The Long Pond Watershed Association backs the plan. In a written statement, the association’s board of directors said it supports “a science-based treatment for the required in-lake phosphorus inactivation.” It also “continues to support improved land use practices, including the creation of buffer strips between homes and shore front and the elimination of the use of chemical fertilizers on pond-front properties.”Vice president Kristen Kimball said the group would have representatives at the hearing.“We look forward to the process moving forward after all the years of work,” she said.Friends of Long Pond opposes chemical treatment, and also will have a contingent of members at the meeting. President Karen Malkus said she believes alum treatment would kill freshwater clams and other creatures that live in the sediment. The group also believes that alum can be a cause for fish kills. Like the watershed group, the Friends calls for responsible land use around the pond, but it also has favored an aeration technology rather than chemical treatment.Malkus said that anyone who wants to attend the meeting and needs a ride should call her at 508-896-4442.Any treatment of phosphorus must be approved by the conservation commissions in both towns. Outlining a possible timeframe, Sumner suggested that, if approvals are secured, alum treatment could begin in May.
One of the Lower Cape’s most beautiful places is our 740-acre Long Pond and the area surrounding it. The wildlife in and around the water is fascinating, and the reflections of the sky across the pond’s surface can be captivating.Children frolic in its shallow edges and families picnic along its shores. People swim in it, fish in it, bike next to it and boat and kayak on it. A lucky few own homes alongside it.The towns with jurisdiction over the pond – Brewster and Harwich – carry a heavy burden. Its leaders and residents must help make the decisions that affect all who use and admire the pond, and who wish to protect it. That’s why the public hearing tomorrow night, Jan. 18, is so important (see news report, Page 1).Brewster and Harwich are poised to go forward with a phosphorus remediation plan that involves applying 73,000 gallons of aluminum sulfate and 37,000 gallons of sodium aluminate into the pond. The idea is that the chemical combination will bind with the phosphorus in the sediment, thus preventing it from entering the water column and causing algal blooms. The alum proposal has been a regular news feature in these pages for the last few years.Is it the right thing to do? We don’t know yet.Most people don’t pretend to understand the science, and we are no exception. But here are some practical questions we’d like to see discussed at the meeting, and in a way that everyone can understand:* Should chemical treatment be a first choice or a last resort?* What are some non-chemical options that would cost about the same as alum treatment?* Would watershed protection around the pond’s buffer be enough to solve the problem over the course of some years?* Would the proposed chemicals enter the water column and, if so, what effects might that have on swimmers and fish?* Has alum successfully alleviated a similar phosphorus problem in another lake the size of Long Pond?* When was the last time there was a major fish kill in Long Pond that can be attributed to an algal bloom caused by phosphorus?The meeting starts at 7 p.m. Thursday at Harwich Town Hall. Anyone who is concerned about this important resource should make the time to attend. The future of the pond and the real estate around it is at stake.