On June 10, 2018, the Green Acton Water Committee welcomed Sue Flint, staff scientist for Organization for the Assabet, Sudbury, and Concord Rivers — OARS — as a guest speaker at our regular monthly meeting. Sue directs the OARS water quality monitoring program, which sends citizen scientists out onto the three rivers and their many tributaries to measure in situ water properties and take water samples for laboratory analysis. Two of OARS’ sampling sites are in Acton: one on Nashoba Brook off of Wheeler Lane, and one on the Assabet River at the Acton Canoe Launch.
Sue’s talk began with an orientation to the three rivers, and then walked us through OAR’s findings on habitat and water quality. Here is the full set of slides from Sue’s presentation, although the slides alone cannot convey the lively discussion and Q&A that accompanied Sue’s presentation.
Probably the most exciting finding, from an environmentalist point of view, was the success story of phosphorous in the Assabet River. Phosphorous enters rivers by runoff from fertilized lawns and fields, and in the discharge from wastewater treatment plants. Excessive phosphorous in fresh water systems enables explosive growth of plant life, which then falls to the river or pond floor and decays.
Powdermill Impoundment of the Assabet River in Acton in 2002
This process, called eutrophication, consumes dissolved oxygen in the water, degrading the habitat for fish and other animal life, especially in the slow-moving water in the impoundments behind dams. Four wastewater treatment plants discharge into the Assabet River: one each in Westborough, Marlborough, Hudson, and Maynard.
Watersheds of the Assabet, Sudbury and Concord Rivers. Wastewater treatment plants that discharge into the rivers are shown as triangles.
When OARS began its water quality monitoring program on the Assabet River in 1992, there was little-to-no effort to remove phosphorous from wastewater. As part of a nationwide cleanup of discharge from wastewater treatment plants (WWTPs) during the 1990s, the plants along the Assabet began to treat for phosphorous, first focusing on summer removal and then expanding to year-round removal.
By 2012, all four Assabet WWTPs were discharging at less than 0.1 mg/L total phosphorous. Total phosphorous level in the river dropped precipitously, and has stayed below the eutrophication threshold range (red line of graph below) for the last five years.
Total phosphorous data from OARS’ citizen scientist sampling program for July and August.
OARS data were essential in making the case for upgrading the Assabet WWTPs, and in documenting the subsequent success. The work is not yet done: levels of nitrogen, another plant nutrient, are still high, and there is still a dense carpet of aquatic plant life in some of the impoundments. But there is plenty of reason to celebrate this victory for citizen involvement in local environmental protection.
All residents of the SuAsCo watershed benefit from OARS’ patient but persistent work in science, advocacy, education, and stewardship. If you would like to learn more or get involved, OARS offers education programs for children and adults and a variety of short- and long-term volunteer opportunities. OARS water quality data and samples are collected by lay people, working under Sue’s careful professional supervision. Volunteers retrain annually to follow sampling protocols and chain of custody procedures that allows the data to be used as evidence in policy making. Green Acton Water Committee members Lucy Kirshner and Kim Kastens are OARS water quality volunteers, and new volunteers for this program are recruited and trained each spring.
There has been a lot of negativity around Concord’s proposal to expand its water treatment plant at Nagog Pond and Acton’s reaction to the same. In this post, let’s take a step back and try to envision what a good outcome might look like. A good outcome would safeguard the ecosystems of Nagog Pond and Nagog Brook, and would be a win-win-win for the three towns that share legal rights to the waters of Nagog Pond.
A good — and possible — outcome would:
scale the water treatment capacity to the size of the pond
develop a protocol for timing water withdrawals and releases so as to minimize harm to the downstream ecosystem and aquifer
collaborate on data collection and hydrologic modeling to provide decision-makers with answers to “what if” questions
construct and administer the water treatment plant as a regional facility with costs and water shared among the three towns
Kim Kastens floated some of these ideas in her talks at the First Parish of Concord on February 25 and at the Acton Senior Center on April 5. (Thanks to the attendees for their enthusiastic reception and insightful suggestions.) This post is not offered as a complete and final answer to the question posed in the title, but rather, as an invitation to consider a wider range of possibilities.
The controversy over Concord’s application to expand its water treatment plant at Nagog Pond has entered a new phase. Negotiators from the Acton and Concord Select Boards have brought forward another draft of the modified special permit decision, with a new set of terms and conditions. The Land Court has remanded the case back to the Acton Board of Selectmen, who will hold a hearing on April 26. A new round of public comments will be accepted, and the BoS will deliberate, and then vote.
If a supermajority (4 out of 5) of the Selectmen vote Yes, then the permit will have been approved with these new terms and conditions. Green Acton has taken a position urging the Selectmen to vote “no.” Our rationale for this position is explained below, followed by links to relevant documents.
Nagog Pond is a kettle hole lake situated on the border between Acton and Littleton. Water flows out of Nagog Pond into Nagog Brook, which flows into Nashoba Brook, and then into the Assabet River.
The town of Concord has been using Nagog Pond as a drinking water source, and in 2015, they applied for permits to greatly expand their water withdrawal and treatment capacity. This application has been controversial.
Article 26 for Acton Town Meeting 2018 is a non-binding resolution which asks Town Meeting to approve an inter-municipal agreement between Acton and Concord. In this agreement, Concord agrees to continue to provide water service to customers along Great Road (Rt 2A) in Acton. In return, Acton agrees to allow Concord to build their proposed Water Treatment Plant on Nagog Pond, and to forebear from efforts to secure water from Nagog for Acton or to limit Concord’s Nagog withdrawals.
Acton Town Hall has released a new version of the draft modified special permit decision for Concord’s application to increase its water treatment capacity at Nagog Pond. This document emerged from closed door sessions between the Acton and Concord Select Boards over the winter. It will be deliberated at a second “Remand Hearing” on Thursday, April 26, 2018, at 7pm in Acton Town Hall. [This is an update: Originally posted date was March 29.]
On February 25, the Forum at the First Parish in Concord was the setting for a lively and well-attended discussion on regional water sharing, using the ongoing controversy over Nagog Pond as a case study. Green Acton member Kim Kastens opened the event with a slide presentation in which she laid out the context for why water issues are now emerging in eastern Massachusetts, and then dived into the water-related aspects of the Nagog Pond case. She ended with two sets of conclusions: the first sketched a potential environment-friendly resolution to the current Nagog controversy. The second was a broader set of lessons learned, applicable no matter what happens at Nagog Pond. Kastens’ full slide deck is here, and her “lessons learned” slide is below:
The Green Acton Water Committee maintains a stream monitoring station on Nagog Brook. This being a low-tech, low-cost installation, our station requires that a volunteer scramble down to the site once a week to read the staff gage, which is like a giant ruler mounted vertically on a pole in the stream.
Last week (January 3), I (Kim) bundled up and trudged down through the snow to the site. The temperature had been below freezing continuously for more than nine days straight, with several nights dipping below 0°F. I was sure I was wasting my time and would find the brook frozen over.
But to my surprise and pleasure, the brook at the gage station was burbling along, as merrily as ever. The water level was a bit lower than it had been in recent weeks, probably because of ice upstream, but the stream was definitely flowing. (Click link below to view video.)
This observation is significant because it confirms that there is substantial groundwater input into the brook. The temperature of groundwater doesn’t vary much over the course of the year, hovering around the average annual air temperature. Here in Massachusetts, that would be approximately 50°F, according to the EPA. During the recent remand hearing on Nagog Pond, Dr. Peter Shanahan, a hydrologist, testified on behalf of OARS that drawing down the water level in Nagog Pond by increasing the water withdrawal into Concord’s proposed water treatment plant could threaten the cold water fishery of Nagog Brook. The threat is two-fold. First, there would be less water flowing over the spillway from the pond into the brook. Second, there would be less hydraulic head to drive groundwater flow laterally into the brook. Groundwater input keeps the brook cool in summer (good for fish) and warm in winter.
Thanks to Dr. Peter Shanahan for confirming (email 3 jan 2018) that groundwater input was the plausible explanation for Nagog Brook’s open water throughout our recent cold snap.