Flood Mitigation Projects
The recommendations from the three prior reports (refer to links below) have been prioritized into Tiers. Tier 1 includes approximately $120 million in drainage improvements from seven drainage areas, including five culverts along Trout Brook. Due to funding constraints, the Town needs to divide the Tier 1 drainage improvements into several phases, each with multiple construction contracts. The initial phase will include approximately $20 million in funding utilized over the next five years.
CDM Smith along with their sub-consultant SLR, is under contract with the Town to provide the permitting and design services of the Tier 1 recommendations. The design and construction in this initial phase will be performed in five of the six drainage areas. Advancing projects in these drainage areas, versus focusing on one drainage area, has multiple benefits, including spreading out the disruptive impact (on traffic, residents, commercial, etc.) of construction, ability to break work up into smaller phases, more manageable construction packages, and providing interim drainage benefits to several drainage areas. Design for the initial drainage improvements requires the survey and preliminary design of a larger upstream area to make sure the size and elevation of the proposed new drainage outfall and pipes is appropriate for the upstream area, especially when considering utility crossings. Design completion is anticipated by the Fall of 2023.
Based on the results of the Town is planning to move forward with the following flood mitigation projects.
- Trout Brook Drive Culvert Improvements (four culverts located between Asylum Avenue and Lindy Lane) - The scope of work is for the replacement of four culverted sections of the East Branch Trout Brook to address flooding caused by the existing undersized structures. New culverts will be precast concrete boxes, sized as indicated in the Flood Mitigation and Culvert Replacement Assessment by Milone & McBroom (now SLR) dated September 2018. The results of the assessment are considered conceptual, final determination of the extent of the culvert length, costs, and staging will be determined during the design when advanced survey and geotechnical explorations and analysis has been performed. CDM Smith will perform the scope of work for each culvert design in accordance with the following design standards.
- FEAT Drainage System (Area 1): The FEAT (bounded by Farmington Avenue, Elizabeth Park, Asylum Avenue and Trout Brook) drainage trunk line starts at the Frederick-Dorset Street intersection, runs north 3.4 miles to Middlebrook, turns west along Middlebrook Road until it turns in the north-west direction while crossing private properties on Griswold Drive and Ballard Drive, and discharges into Trout Brook. The preliminary and final design will focus on the downstream potion of the drainage system along Middlebrook Road from Trout Brook to Cumberland Road.
- Fern Street East Drainage System (Area 2): The area just south of the FEAT area is designated as Area 2 and includes eight separate drainage systems. The Fern Street East drainage system is located east of Trout Brook, in the central part of the area. The system consists of 24 pipe segments ranging in diameter from 12 to 42 inches. The preliminary and final design will focus on three areas where system deficiencies exist: Dover Road just south of Fern Street, Bretton Road both north and south of Fern Street, Penn Drive north of Fern Street and Fern Street between Penn Drive and Bretton Road.
- Arundel Avenue Drainage System (Area 4): The Arundel Avenue drainage system is the largest system within Area 4 and conveys flow in a northerly direction, from Brace Road, down Brunswick Avenue to Whitman Avenue, then down Arundel Avenue to Fern Street, then through private property (including the School for the Deaf) to North Main Street and to the 42-inch outfall at Trout Brook. The preliminary design for this area includes Whitman Avenue from Argyle Avenue to North Main Street, Arundel Avenue just north and south of Whitman Avenue, North Main Street between Whitman Avenue and Loomis Drive, and Loomis Drive from North Main Street to Trout Brook. The final design includes a smaller area from the intersection of Arundel Avenue and Whitman Avenue to the outfall on Loomis Drive.
- St Joseph’s Tributary Drainage System (Area 5): The St. Joseph’s Tributary system includes a complex drainage system starting in the northeastern portion of the Area 5 watershed near Mohawk Drive and Norwood Road ending at the twin 42-inch outfalls just south of Lawler Road and Wiltshire Lane. The preliminary design includes a portion of Haynes Road and Lawler Road just west of Wiltshire Lane, Wiltshire Lane from Lawler Road to Albany Avenue, Albany Avenue just west of Wiltshire Lane, and a portion of Miamis Road and Sequin Road just north of Albany Avenue. The final design includes a portion of the preliminary design area and includes Wiltshire Lane from just north of Haynes Road to the outfall near Lawler Road.
- Linnard Road Drainage System (Area 3): A Groundwater Study for the Trout Brook watershed in the neighborhood west of Trout Brook that includes Montclair Drive, Linbrook Road, and Linnard Road is underway. A review of existing data and historic maps was completed to provide some context for recent instances of apparent groundwater seepage into basements and yards. The objective of the review was to determine if high groundwater levels are expected in this neighborhood and to better understand potential next steps to take to lessen the impacts of high groundwater in the future. Monitoring wells will be installed along Linbrook Road and tested to gain a better understanding of the subsurface conditions within a portion of study area 3. This will serve as a pilot to determine the feasibility of a passive groundwater lowering project in the rest of the neighborhood west of Trout Brook.
The six study areas are shown on the map available here.