TOWN OF ARLINGTON VISION 2020 ENVIRONMENT TASK GROUP
RESERVOIR COMMITTEE
April 24, 2001  Meeting Notes

 

In attendance: Rich Bento, Ralph Elwell, Margaret Fitzgerald, Cathy Garnett, Gerri Gross, Brian Hasbrouck, Jane Howard, Elizabeth Karpati, Ann LeRoyer, Leslie Mayer, Sharon Stafford, Susan Wheelock, David White; Mark Mitsch, consultant from Weston & Sampson.

The meeting was facilitated by Leslie Mayer. The minutes are by Elizabeth Karpati.

Presentation by Mark Mitsch of Weston & Sampson:

  • (There was an article in last week’s Arlington Advocate about the dam project being "put off" from fiscal year 2002 to FY 2003 but it is a bit confused.)

Water Level:

  • High water level (with gate up) is 158, not 159 as previously stated (determined by spillway height, which is 158).
  • Lowering the water level permanently to 153 would require an environmental impact statement under the Mass. Environmental Protection Act because it would dry out the wetlands; an EIR would be both lengthy and costly. (It takes about 2 weeks to lower the water level by 5 ft.)
  • But wetlands would not be dried out completely: instead of being flooded regularly for two months each summer, they would be flooded irregularly when the Res was used for flood control in big storms. Gate is to be repaired so that flood control is possible.
  • If gate was removed so that the Res cannot be used for flood control, this would increase flooding downstream during big storms and would presumably require an EIR anyway.
  • Test borings have been completed; they show that the berm around the swimming area is "highly pervious." The latest plans contemplate keeping the water high in the summer and thus saving the cost of leakproofing the berm.
  • Dredging to improve the capacity for flood control would also require an EIR, and would make no difference in the summer if water level kept high.
  • No borings were done in the Res, thus whether it has a clay liner is unknown.

Spilllway:

  • Existing spillway is about 20 ft. wide; it could handle a 500-year storm but with no "freeboard" (water level would rise to the very top of the dam); it could not handle the "1/2 PMF" storm.
  • To provide a safe amount of freeboard in a 500-year storm, the spillway would have to be widened by about 60 ft; for a ½ PMF storm by about 180 ft. (A spillway adequate for a given storm lessens the danger of the dam breaking in that storm.)
  • The March 22 storm which filled the Res was a "50-year" storm; flooding started in Colonial Village before water from the Res started flowing through the spillway. The 1996 storm which flooded the Kenmore subway station was a "75-year" storm.
  • New spillway would have to be lined with concrete, or something through which grass but not shrubs could grow. Path around the Res could go down to bottom of spillway, or go over it on a bridge or walkway.

Landscaping options:

  • Central area of dam (a piece between outflow and stump dump) is natural, so trees would not have to be removed from that part.
  • Inside face of rest of dam (toward the water) would have to be cleared and riprapped.
  • Where existing trees have to be removed, possibly small (10-15 ft.) flowering trees could be planted in mounds over a liner that keeps their roots from growing down into the dam. This has been done over landfills, e.g. Danehy Park in Cambridge. But there is a question of whether this is permissible on a dam, because of the extra weight of mounds and trees and because this would make inspection of the dam more difficult.
  • Planting trees on the fill beyond the dam in the wide area would also require a root barrier between fill and dam.
  • There will be a meeting of dam safety officials in Marlborough in July which will cover the pros and cons of various kinds of plantings on dams.
  • A slightly meandering walking path on top of the dam is planned.
  • Other ideas include overlooks for fishing, and arbors.
  • Possible link with bikepath, to provide an alternative to people walking across Hurd Field. But bike access from bikepath is of dubious desirability (path around Res should be for walking only, not biking). A sign on bikepath, pointing to the Res, would be OK.
  • For parking lot, soil stabilizer rather than asphalt should be used.

Public Meeting:

  • Date has been set, and Town Hall reserved, for May 22. Meeting should be held now, even if plans are not definite, to try to answer questions that may have been raised by the Advocate article and to reassure the public that swimming will continue.
  • Meeting should be more for gathering input than presenting a plan. Explain why the state is requiring action on the dam; options; roles of entities like Parks & Rec and ConCom. (ConCom should be invited but doesn’t have to participate.) Once we have more solid plans, there should be a public hearing on them.
  • Format: keep presentation uninterrupted, have questions afterwards; let people submit written questions to be answered later (e.g. on website) if we run out of time.
  • Be ready to explain that the Res cannot be the solution to flooding problems. Mill Brook is under DPW’s jurisdiction on public property, but much of it flows through private property, including Colonial Village; developer of C.V. relocated the brook! C. Abbott has suggested a retention pond in Great Meadows to hold some of the water that doesn’t go through the Res.
  • Displays/handouts:
  • Consultant’s display.
  • Joe Connelly’s information sheet about use of the Res for swimming.
  • ConCom’s "History of the Res" chart prepared for Town Day a few years ago: D. White will ask it for permission to use an updated version, and for clarification of a few points.
  • Perhaps a "glossary" prepared by Rich Bento.
  • How many people not already involved would come to the meeting? Alternative ways of presenting our information: press release for Advocate, handout for people buying Res tags.
  • Jim Marzilli plans to come to the meeting; should be asked to check on the possibility of getting any state funds.
  • Publicity (Leslie and Brian will work on it): Arlington Advocate, Lexington Minuteman. Website (Bob Sprague). Drake Village newsletter. Posting where possible, e.g. community or supermarket bulletin boards. Door-to-door distribution of flyer in Res area.

Other business:

  • Earth Day events went well: about 15 people turned out for Karsten Hartel’s bird walk and 5 including two from the Spy Pond Committee for Brian Hasbrouck’s walk on the history and future of the Res
  • Busa Farm is being hounded by developers. Owners want to keep it a farm but "don’t want restrictions." An "agricultural preservation restriction" would not help: it only keeps taxes low as long as the land is used for farming.
  • We should have a cleanup around the Res. Sharon has a friend who may be willing to organize it.

Next meetings: 7:30 p.m. Tuesday, May 15, Jefferson Cutter House (note location). Monday, June 18, 7:30 PM, location TBA.

 Home ] Up ]