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CAPITAL EXPENDITURES COMMITTEE REPORT TO 2016 ATM Stormwater Drainage and National Pollution Discharge Elimination Systems (NPDES) Storm drains collect stormwater along Town streets and parking areas, and convey this water to streams and other bodies of water. The storm -drain pipes and the pavement -level catch basins that direct storm water to them occasionally fail due to heavy loads passing over them and/or loss of supporting soil around them thereby creating holes in the street. In addition, as streets are repaired and repaved, it is frequently discovered that the storm - drainage system is seriously deteriorated. Concurrent drainage- system repairs are required to prevent further deterioration and to protect newly paved streets. It also is necessary to study and repair drains where overflow conditions develop and/or complaints are received. The goal of the Federal National Pollutant Discharge Elimination System (NPDES) program, under which the Town has a State - administered permit, is to maintain water quality. New permitting regulations are anticipated that are expected to increase costs and complexities of this work in future years. Recent drainage improvements have included Spring Street and Woburn Street. Paul Revere Road is in progress. Continuing trouble spots include the watersheds of the Vine Brook, Mill Brook, Beaver Brook and Kiln Brook, as well as other areas. This Committee welcomes Engineering's leadership and efforts, in compliance with Federal Environmental Protection Agency (EPA) requirements, to improve the water quality in Lexington's streams and ponds while protecting the Town's investment and structural integrity of its streets. (See Article 10(d)) Comprehensive Watershed Storm Water Management Systems In order that the Town's storm - drainage system capacity is maintained to handle runoff from impervious surfaces, the Town must manage its storm -water runoff associated with its 18 brooks and three watersheds. Additionally, sediment deposits, organic debris, and refuse can impede the flow of water through watershed areas, and cause flooding and damage to private property, thus creating liabilities for the Town. To date, the Charles River, Shawsheen River, and Mystic River watershed - management plans have all been completed. Design work has been completed and construction is under way for the Willard Woods "daylighting" and drainage improvements, as well as stream -bank stabilization for the Vine Brook in the Saddle Club Road area. The Whipple Brook storm -water design is underway. For the FY2017 funding request to address other priority areas, see Article 10(f)). [Note: There is some overlap with Town -Wide Culvert replacement as some projects require both culvert repair and stream- management planning. Culvert Repair There are more than 50 culverts in Town. Many of the older culverts are near or at failure. A culvert is defined as a pipe or drain that carries a stream or ditch under a roadway. DPW's engineering program for on -going culvert inspections has confirmed a need for culvert replacement and extraordinary repairs. This is a companion effort to the ongoing Comprehensive Storm -water Management Watershed work. The 2011 ATM Article 7(s) appropriated $65,000 for the review, design, and permitting for repairs to the three culverts under the access road to the Hartwell Avenue Compost Facility. The 2012 ATM Article 12(d) appropriated $390,000 for replacement of those three culverts and for D &E for repairs to culverts identified in storm - drainage studies. The three culverts at the entrance to the Compost Facility and an additional culvert on Concord Avenue near the Belmont Town Line were replaced in 2014. In 2015, worked was funded for the culvert work under Revere Street at the North Lexington Brook, and the culvert under Concord Avenue at Hardy's Brook. This work, as well as the Bikeway culvert which was funded for FY2016, has been permitted and is now in the early stages of construction. For the FY2017 funding request, see Article 10(i)). Public Grounds The Town owns approximately 630 acres of land of which approximately 110 acres are in parks, playgrounds, conservation areas, athletic facilities, school grounds, and historical sites. In addition, Town staff administers and maintains four cemeteries with a combined area of a little over 30 acres. The 21