Weymouth-02

Weymouth, Philips Creek

42.238398, -70.949330

Dimensions: 7ft diameter, 5ft height
Condition: Fair
Comments: Stone culvert appeared to be in fair condition. Longitudinal cracks were observed on upstream end of the headwall. Upstream end of the headwall had a steel trash screen installed across the culvert mouth. The bottom portion of the trash rack was corroded.

Comprehensive field assessment conducted in 2024

Upstream Invasive Species: Yes
Downstream Invasive Species: Yes
Invasive Species Notes: Phragmites exists further upstream from culvert
Additional Comments (2024): Healthy mix of low and high marsh adjacent to culvert but phragmites begins to encroach on channel as you move upstream. Islands within the marsh are also progressing toward upland species like red oak. Tide gate has deteriorated and may be allowing more tidal exchange than designed. Further opening may promote regrow of the upstream salt marsh and islands.

Legacy data from previous surveys and documentation

Invasive Species: Yes
Restoration Status: Not Applicable
Invasive Comments: Upstream area varied significantly. Phramites, upland vegetation, and Spartina Alterniflora islands were observed. Vegetation was indicative of some level of salt water influence, but not enough volume to inundate the marsh top which was mainly comprised of upland vegetation. It appeared that the marsh had potentially subsided over time.
Restoration Comments: Large upstream wetland area with good restoration potential. A marina worker indicated that upstream residents had complained of flooding in the past, but it was unclear if the flooding was a result of tidal inundation, stormwater influence, or a combination.

General Comments: Tide gate is located on Pearl Street at the bottom of the headwall in channel directly adjacent to the marina.
Operation Plan: No
Operation Comments: Tide gate appeared to be installed for upstream flood protection purposes.
Gate Comments: Large wooden flap gate was in poor condition. The bottom half of the tide gate was rotting. The tide gate was installed in such a way that a seal was not created against the headwall thereby allowing some level of tidal exchange at all tidal levels. The tide gate hinges appeared to be operable; however, the tide gate was so waterlogged that it was not possible to fully open.

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: Top of HW El (D/S) = 8.92’; Inv Measuredown = 9.50’; TG Inv = 8.92 – 9.50 = -0.58’ 2) Upstream Tidal Influence: Top of headwall LiDAR Elevation = 7.45’; Staining Measuredown = 4.91’; U/S Tidal influence = 7.45 – 4.91 = 2.54’. 3) Downstream Tidal Influence: Top of headwall LiDAR elevation = 9.50’; Staining Measuredown = 6.83’; D/S Tidal Influence = 9.50’ – 6.83’ = 2.67’
Other Comments: Stormwater runoff problems / Phragmites is getting established
External Data Comments: Pearl Street Flood Extent - LiDAR (Other)