Weymouth-02
Weymouth, Philips Creek
42.238398, -70.949330
Technical Specifications
Basic Properties
- Type
- Flap Gate
- Material
- Wood
- Control
- —
- Condition
- Poor
- Geometry
- Rectangular
- Status
- Active
- Number of Gates
- 1
Operator & Management
- Operator Type
- PUBLIC
- Operator
- Town of Weymouth
- Permits
- —
- Purpose
- Flood Protection
Dimensions & Elevations
- Dimensions
- 8ft diameter, 7ft height
- Invert Elevation
- -0.58 NAVD88
- Installation Date
- —
- Tidal Influence
- Upstream: 2.54 NAVD88, Downstream: 2.67 NAVD88
Culvert Details
- Restriction Type
- Roadway
- Geometry
- Rectangular
- Material
- Concrete
- Bottom Material
- Stone
- Number of Pipes
- 1
- 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.
Salt Marsh Field Assessment Results
Comprehensive field assessment dataPhysical Conditions Assessment
Channel Conditions
- Channel Alteration and Ditching
- Moderate (133-398 ft/acre)
- Channel Constriction
- Equal to channel
- Channel Erosion
- Moderate (10-60% of bank)
- Sediment Deposits
- None
Blockages
- Debris Blockages
- None
- Evidence of Overtopping
- No
Ecological Assessment
Habitat Observations
- Ecological Impairment due to Tide Gate
- Moderate
- Crab Burrow Intensity
- Limited (<10% banks are densely
- Ponding and Die-off Depressions
- Limited(<10% of marsh platform
- Phragmites Present
- Moderate (10-60%)
Invasive Species
- Upstream Invasive Species
- Yes
- Downstream Invasive Species
- Yes
- Invasive Species Notes
- Phragmites exists further upstream from culvert
General Comments
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.Habitat Transects
First Transect (50 yards upstream of tide gate)
Second Transect (150 yards upstream of tide gate)
Third Transect (300 yards upstream of tide gate)
No data
Restoration Potential
Assessment
- Salt Marsh Impairment due to Tidal Restriction
- Moderate
- Potential Extent of Marsh Restoration
- Moderate
- Implementation Feasibility
- High
- Restoration Priority
- High
- Recommended Improvement Type
- O&M and Infrastructure
Notes
Site shows moderate salt marsh impairment due to restricted tidal flow. Replacement with self-regulating tide gate could restore approximately 5-8 acres of degraded marsh habitat. Good access for construction equipment. Regional coordination completed with town DPW and conservation commission.Historical Records
Environmental Data
- 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.
- Upstream Area
- Salt Marsh: >10acres
Notes & Comments
- 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’
- Visit Comments
- —
- Other Comments
- Stormwater runoff problems / Phragmites is getting established
- External Data Comments
- Pearl Street Flood Extent - LiDAR (Other)
Part of the Massachusetts Bays Program© 2026 Massachusetts Bays Program. Monitoring tidegates across Massachusetts.