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CAPITAL EXPENDITURES COMMITTEE REPORT TO 2022 ATM& STMs 2022-1 & -2
<br /> Wastewater System
<br /> The sanitary-sewer system has about 176 miles of main sewer line and 8.5 miles of pumped "force main"
<br /> lines, and, like the water-distribution system, has sections that date back to the early 1900s. Due to age-
<br /> related deterioration, some sections are susceptible to storm-water inflow and groundwater infiltration
<br /> which increases the total flow to the Massachusetts Water Resources Authority (MWRA) treatment
<br /> system, resulting in increased charges to the Town, and causing overloading of parts of the system, with
<br /> the potential to spread waterborne disease. Engineering has an ongoing program of investigating,
<br /> evaluating, repairing, and replacing sections of the system. This work has been partially funded by the
<br /> MWRA Infiltration/Inflow (I/I) Local Financial Assistance Program, which provides grant and interest-
<br /> free loan funding for member communities; the current allocation provides for $1.56M, of which 75% is
<br /> grant and 25%is a no-interest loan. For the FY2023 funding request, see Article 14(b).
<br /> The system has ten sewage-pumping stations that need continual maintenance and periodic major
<br /> upgrades. In July 2013, the engineering firm Wright-Pierce performed a detailed survey of the pump
<br /> stations, generating a 20-year repair/replacement plan which the Town has been following. This year's
<br /> request is consistent with that plan. (See Article 14(a).)
<br /> Of the nine pumping stations determined to be large enough to warrant backup power, seven stations
<br /> (Main Station, Concord Avenue, Potter Pond, Brigham Road, Constitution Road, Marshall Road, and
<br /> Worthen Road) have had backup electric-power generators installed during the pump station upgrades.
<br /> Significant improvements to the main pump station on Bedford Street were completed in October 2016,
<br /> which included heating, ventilation, and air-conditioning (HVAC) upgrades to bring it up to current code
<br /> requirements, installation of Variable Frequency Drive motors, which provide energy savings and noise
<br /> reduction in the sewer force main, on all the pumps, and a surge tank.
<br /> Design work for the Hayden Avenue and North Street Stations is complete, to be followed by
<br /> construction, and backup generators will be installed in these two locations. A contract for the Hayden
<br /> Avenue project has been awarded. Once all station upgrades have been finished, the capital plan to
<br /> maintain this critical infrastructure will again be re-evaluated and updated.
<br /> Heavy equipment and trucks used by the Sewer Division are procured with Sewer Enterprise Funds that
<br /> are funded by Sewer rate-payer fees,additional fees and charges, investment income, and connection fees.
<br /> Where equipment is shared with the Water Division,the costs are split.
<br /> Dam Restoration
<br /> The Massachusetts Department of Conservation and Recreation mandates that every dam in the State that
<br /> is rated as a "significant-hazard dam" or "high-hazard dam" be inspected every five years. These ratings
<br /> are assigned to dams based on the risk of the impact if the dam fails and the water is released; the ratings
<br /> are not about the dam's state of repair. There are two dams at the significant-hazard impact level in
<br /> Lexington: Butterfield Dam on Lowell Street and Old Reservoir Dam on Marrett Road. Both dams have
<br /> had recent repairs and reconstruction and comply with all State codes and requirements.
<br /> Stormwater Drainage and National Pollution Discharge Elimination Systems (NPDES)
<br /> Storm drains collect stormwater along Town streets and parking areas and convey this water to streams
<br /> and other bodies of water. The storm-drain pipes, and the 4,700 catch basins that direct stormwater to
<br /> them, occasionally fail due to heavy loads passing over and/or loss of supporting soil, thereby creating
<br /> holes in the street. In addition, as streets are repaired and repaved, it is often discovered that the storm-
<br /> drainage system has become seriously deteriorated. Concurrent drainage-system repairs are required to
<br /> prevent further deterioration and to protect the newly paved streets. Drains also have to be analyzed and
<br /> repaired where overflow conditions develop or complaints are received.
<br /> The goal of the Federal NPDES program, under which the Town has a State-administered permit, is to
<br /> maintain water quality in the drainage system. New permitting regulations became effective on
<br /> July 1, 2018. Those new regulations represent an unfunded obligation that is expected to increase both
<br /> operating and capital costs and complexity of this work in future years; however, because of the Town's
<br /> aggressive efforts, it expects to remain compliant in FY2023. In anticipation of this mandated program
<br /> and the ever-increasing needs of managing stormwater, a number of municipalities nationwide, including
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