Pinnacle at Spear

Problem

The Pinnacle at Spear neighborhood is situated within two stormwater impaired streams (Bartlett Brook and Munroe Brook). The medium density residential neighborhood’s existing stormwater system consists of a stormdrain and drainage pipe network that empties into one of four separate detention basins. These basins were constructed prior to the State of Vermont’s adoption of modern requirements related to the detention and treatment of stormwater.

Description

In 2017, the Lake Champlain Basin Program (LCBP) awarded the City a grant to evaluate the neighborhood and prepare an engineering design for retrofit of the existing detention basins. The City, Pinnacle at Spear Homeowners Association, and an engineering consultant developed designs to retrofit two detention basins into subsurface gravel wetlands, retrofit one linear detention basin into a sand filter with added detention, and upgrading one linear detention basin to eliminate short-circuiting, provide pre-treatment, and reduce peak discharge rates.

Benefit

Retrofit of the Pinnacle at Spear Detention Basins will provide improved treatment for 36.42 acres, including 12.23 acres of impervious surface.

In addition, these stormwater treatment practices detain excess volumes of stormwater runoff and slowly release water to the brook. This helps prevent erosion of stream banks and reduce the risk of downstream flooding.

Best Management Practices

Gravel Wetlands, Sand Filter, Detention Basin, Swirl Separator.

Timeline

The City of South Burlington is currently requesting bids for the Pinnacle at Spear Stormwater Improvements project as described in the contract documents. Project work generally includes earthwork, rip-rap, swirl separators, outlet structures and other related items in retrofitting four (4) existing stormwater detention basins into two (2) new gravel wetlands, one (1) sand filter, and one (1) grassed detention practice. Sealed bids will be received at the South Burlington Department of Public Works Office located at 104 Landfill Road, South Burlington, VT until 1:00 PM on August 23, 2018. There was a non-mandatory pre-bid conference at 1:00 PM on August 9, 2018 at the South Burlington Department of Public Works Office located at 104 Landfill Road, South Burlington, VT. Copies of the Contract Documents and Plans are available from Blueprints Etc (20 Farrell St, South Burlington, (802) 865-4503 ). All questions shall be directed to Dave Wheeler, Assistant Stormwater Superintendent: 104 Landfill Road, South Burlington, VT 05403 dwheeler@sburl.com (802) 658-7961.

Total Project Value

$500,000

Funding Sources

The Lake Champlain Basin Program, Ecosystem Restoration Program, Clean Water Block Grant Program, the Pinnacle at Spear Homeowners Associations, and the South Burlington Stormwater Utility.

Last Updated: 8/20/2018