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HomeMy WebLinkAbout2023-03-09_205 Scudders Monitoring Report_RedMONITORING REPORT 2022 To: Conservation Commission Attn: Darcy Karle, Agent 200 Main Street Hyannis, MA Project: Bank Stabilization Location: 205 Scudder’s Lane, Barnstable MassDEP File: SE3-5790 Project No: C19264.01 Report Date: 03-09-2023 Present on Site: Catherine Ricks – CEC Weather: Sunny, 48°F Wind: N 9 mph Date of Site Visit: 02-14-2023 Time: 11:00 – 12:00 Observations: Coastal Bank – The toe of the Coastal Bank is armored with a rock revetment along most of the property. On the western side of the property, the revetment has a taper, and the revetment ends about 100 feet from the existing boathouse. Between the end of the revetment and the boathouse, bank nourishment was placed, covered with coir netting, and planted with North American beach grass. The lower portions of the bank nourishment and beach grass plantings have eroded (Photo 4). The upper portion of the nourishment in the last, approximately 50 feet before the boat house, remains in-tact as well as the beach grass plantings (Photo 4). The Bank, extending 40 feet from the end of the revetment toward the boathouse, has continued to fail over the last year. Not a significant change, but it is still unstable with tree roots exposed (Photo 3). The areas along the face of the Coastal Bank above revetment are stabilized with turf reinforcement matting (TRM). The TRM is well-anchored along the bank. The vegetation planted is growing well. There is a concentrated area adjacent to the end of the revetment that has eroded more than the other unarmored portions of the Coastal Bank. In this area there are signs of upland erosion caused by rain runoff, along with signs of coastal erosion caused by storm waves, however, there is little change from the previous year’s condition. The vegetation in this area is not growing as well as the rest of the bank. Overall, the Coastal Bank looks well stabilized and vegetated except in the area adjacent to the west end of the rock revetment where there are signs of runoff and coastal erosion. Coastal Beach – The upper portions of the Coastal Beach along the toe of the Coastal Bank show no change from the previous year’s conditions. Upland area/ Coastal Bank Buffer Zone– The vegetation planted along the top of the bank look healthy. The backyard had a mix of sod and grass seed planted; both of which are growing well. The upland area above the eroded area of the bank was inspected. The grade in this area is shallow, but there are signs that runoff water may be overtopping the bank in this area. There are no signs of stormwater runoff overtopping the Coastal Bank along any other area of the property. Summary: The site was inspected by Coastal Engineering Company, Inc. to document the existing conditions of the site since the completion of the construction of the shorefront protection system. Items documented include the plant survivability, evidence of erosion, condition of the shorefront protection system, stability of the Coastal Bank, and recommendations. Plant Survivability – The beach grass that was planted along the lower portions of the bank on top of the bank nourishment did not survive due to storm tides eroding the nourishment. The grasses along the face of the Coastal Bank look healthy and densely populated. The plants installed along the top of the bank appear to be alive and healthy, dormant during the site visit due to the time of year. There is one area along the Coastal Bank near the western end of the revetment where the plants are sparce due to upland and coastal erosion undermining the TRM. Evidence of Erosion – There has been no major changes to the shoreline erosion from the previous year’s conditions. The lower portions of the Coastal Bank between the revetment and the boathouse show signs of erosion due to storm tides. Some of the bank nourishment and much of the beach grass plantings have been eroded away. One area of the bank adjacent to the end of the rock revetment shows signs of upland erosion caused by rain runoff with no degradation from the previous year’s conditions. Condition of the Shorefront Protection System – There has been no major changes to the beach elevation from the previous year’s conditions. Overall, the system is in good shape. The revetment shows no signs of slumping or settlement. A portion of the bank nourishment and beach grass plantings has been eroded away, but the upper portions of the bank nourishment remain and are sparsely vegetated with beach grass. The coastal grasses and shrubs along the face and upper Coastal Bank show signs of growth and appear to be healthy. The TRM remains anchored to the face of the bank. One area of the bank adjacent to the end of the rock revetment shows signs of erosion due to upland stormwater runoff. The grasses in this area are not growing as well as the rest of the bank, and a scarped area has formed underneath the TRM though no significant change from the previous year’s conditions. Stability of the Coastal Bank – Overall the Coastal Bank is stable. Most of the toe of the bank is armored with the rock revetment. The toe of the unarmored portion of the Coastal Bank shows signs of erosion but has not been compromised to the point of slumping or failure. The face of the bank is well vegetated, as the beach grass and other grasses are growing well. Recommendations – Overall the shorefront protection system is in good condition. Small maintenance activities as noted in the previous year’s report could be completed to potentially promote the longevity of the system. See photographic documentation below. Submitted by: Catherine C. Ricks, P.E. Project Manager, CEC Photo 1: Rock Revetment and Vegetated Coastal Bank. (Left: 2021, Right: 2022) Photo 2: Coastal Bank between Revetment and Boathouse. (Left: 2021, Right: 2022) Photo 3: Eroded Area of Coastal Bank Adjacent to the Revetment. (Left: 2021, Right: 2022) Photo 4: Bank Nourishment with Coir Netting and Beach Grass Planting. (Left: 2021, Right: 2022) Photo 5: Backyard Area with Sod and Seeded area. (Left: 2021, Right: 2022) Photo 6: Vegetation Along Upper Bank. (Left: 2021, Right: 2022)