Quincy-01B

Quincy, Black's Creek

42.266459, -70.997106

Comprehensive field assessment conducted in 2024

Upstream Invasive Species: Yes
Downstream Invasive Species: No
Invasive Species Notes: Limited to patches along the upland border.
Additional Comments (2024): Upstream side appears to be managed as a salt pond with surrounding salt marsh. Tide gates appear to be regularly managed and allowing adequate tidal exchange. Culvert may slow draining of the marsh. Further widening of culvert may increase flushing rate which would increase low marsh community and reduce erosion but marsh is in good shape otherwise.

Legacy data from previous surveys and documentation

Invasive Species: No
Restoration Status: Complete
Invasive Comments: Area upstream of the tide gate appeared to be a large, healthy marsh with adequate tidal flushing as a result of the relatively recently installed tide gates and culverts (i.e., circa 2010).

General Comments: Tide gates are located under Quincy Shore Drive, a short walk south of Caddy Memorial Park. Additional data needed: O&M, Engineering Plans, and Permits from when Tide Gates were installed.
Operation Plan: No
Operation Comments: O&M plan is likely present. Appears to be designed to deploy based on float switch when water level reaches float at approx. 12'.
Gate Comments: Set of 3 identical metal tide gates with hinge installed underneath road. Tide gate diameter and height is approximate and should be confirmed with Engineering Plans. There are locations along the concrete headwall to insert metal stop logs for additional water level control.

Elevation Comments: Staining was apparent on the upstream (U/S) and downstream (D/S) ends of the headwall (HW) so approximate extent of U/S and D/S tidal influence was able to be assessed in addition to tide gate (TG) invert elevations. The below lists measuredowns taken with a surveyors rod and corresponding top of headwall LiDAR elevations (NAVD88 datum). 1) TG Inv (in this case measured to invert of U/S culvert): Top of HW El (U/S) = 11.32’; Inv Measuredown = 15.17’; TG Inv = 11.32 – 15.17 = -3.85’ 2) Upstream Tidal Influence: Top of headwall LiDAR Elevation = 11.32’; Staining Measuredown = 9.25’; U/S Tidal influence = 11.32 – 9.25 = 2.07’. 3) Downstream Tidal Influence: Top of headwall LiDAR elevation = 11.38’; Staining Measuredown = 8.1’; D/S Tidal Influence = 11.38’ – 8.10’ = 3.28’
External Data Comments: MA DEP Order of Conditions 8.7.2013 MA General Permit Application 4.29.2013 US ACOE NAE-2012-2284 Permit Application 3.28.2013 Tide Gate Operation and Maintenance Plan 12.19.2013 NOAA Comments on Permit NAE-2012-2284 6.30.2014 (Other) US ACOE Fenno St. Comments on Permit NAE-2012-2284 (Other) EPA Letter on Permit NAE-2012-2284 3.25.2014 (Other) MA CZM Comments on Permit NAE-2012-2284 4.1.2014 (Other) Black Creek Tide Gate Acceptance of Transfer 1.18.2002 (Other)