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HomeMy WebLinkAbout2023-03-10_211Scudders Monitoring Report_redMONITORING REPORT 2022 To: Conservation Commission Attn: Darcy Karle, Agent 200 Main Street Hyannis, MA Project: Bank Stabilization Location: 211 Scudder’s Lane, Barnstable MassDEP File: SE3-5788 Project No: C19248.01 Report Date: 03-10-2023 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 lower portion of the Coastal Bank shows signs of erosion, but is stabilized with a bioengineered fiber roll array. The coir netting covering the fiber rolls is damaged in an area along the bank, allowing nourishment to erode through. The areas along the upper Coastal Bank, above the fiber rolls are stabilized with turf reinforcement matting (TRM). The TRM is well-anchored along the bank except for in one area along the western lot line. The previous signs of runoff erosion coming from the upland and eroded material from underneath the TRM are still present but no worse than the previous report. The vegetation is growing well on the blanketed bank. There is surviving beach grass in the areas where sacrificial nourishment still exists. Overall, the Coastal Bank looks stabilized and vegetated except in the area near the western lot line where there are signs of runoff erosion from the upland. There are plans for upland stormwater runoff to be addressed Spring 2023. Coastal Beach – The upper portions of the Coastal Beach along the toe of the Coastal Bank has a heavy amount of wrack. The damaged portion of the coir netting that was once lying on the upper beach area is completely gone. Town Landing – The upper beach area directly west of the boat ramp had previously significantly dropped in elevation. Beach elevation has remained stable, a shoreline protection riprap feature has been installed and vegetated buffer along the parking lot has been established. The plantings seemed to be in good health, though dormant during the site visit. Summary: The site was inspected by an engineer from Coastal Engineering Company, Inc. to document the existing conditions of the site annually since the completion of the construction of the shorefront protection system. Items documented include the plant survivability, erosion, condition of the shorefront protection system, stability of the Coastal Bank, and recommendations. Plant Survivability – There has been no major change to plant survivability from the previous year’s condition. The beach grass that was planted along the lower portions of the bank on top of the sacrificial nourishment were not replanted. Most of the sacrificial nourishment and associated beach grass remained eroded. The plants that were installed above the fiber rolls are surviving well. The plants look healthy and densely populated. There is one area along the Coastal Bank near the western lot line where the plants are sparce due to upland erosion undermining the TRM however they are growing and do not show a decline from the previous year. The plantings on the Town property seem to be in good health and are helping to support the area around the ramp. Erosion – There has been no major change to beach elevation or toe of the bank from the previous year’s condition. The lower portions of the Coastal Bank show minor signs of erosion. Tears in the coir netting covering the fiber rolls has allowed some nourishment to erode through. Most of the sacrificial nourishment eroded and was not replaced. The beach grade adjacent to the boat ramp has not dropped since the previous report. One area of the bank near the western lot line shows signs of upland erosion caused by rain runoff but no degradation from the previous year. Condition of the Shorefront Protection System – There has been no major change to the condition of the shorefront protection system from the previous year’s condition The shorefront protection system that was installed consists of an anchored fiber roll array along the toe of the Coastal Bank that was covered with sacrificial nourishment and planted beach grass. Above the fiber roll array on the face of the Coastal Bank is an anchored turf reinforcement matting (TRM) with a mix of coastal grasses planted underneath the fabric. Overall, the system is in good shape. Most of the sacrificial nourishment and beach grass plantings remain eroded away, but the fiber roll array remains properly anchored and does not show any signs of damage. The coastal grasses show signs of growth and appear to be healthy. The TRM remains anchored to the face of the bank. One area of the bank near the western lot line shows signs of erosion due to upland rain runoff but no degradation from the previous year. The grasses in this area are slowly growing, and the rut that has formed has not grown or changed shape. Stability of the Coastal Bank – There has been no major change to stability of the Coastal Bank from the previous year’s condition. Overall, the Coastal Bank appears stable. A majority of the toe of the bank continues to be in place and stable though the fiber rolls are uncovered and open to UV degradation. A small section has tears in the coir and has slow degradation. Degradation will continue if no maintenance occurs. The upper bank has vegetation growing and stability that will continue growing with a stable toe. Recommendations – Overall the bioengineered system is in good condition. Repair to fiber rolls and maintenance activities previously mentioned could be completed to potentially promote the longevity of the system. The exposed areas of the fiber rolls could be covered with sacrificial nourishment. This would help prevent UV ray degradation to the fiber rolls in the short- term. It is likely that the sacrificial nourishment will eventually erode again and require continual maintenance which leads to less repair and maintenance of the other shoreline features. The plantings on the Town Landing property should be monitored for continued growth and stability. See attached pictures below. Submitted by: Matthew Turcotte – Staff Engineer, CEC Photo 1: Coastal Beach and Coastal Bank Showing Fiber Rolls and Vegetation in Good Shape. (Left: 2021, Right: 2022) Photo 2: Coastal Beach Showing Damaged Coir Netting and Wrack. (Left: 2021, Right: 2022) Photo 3: Area of Coastal Bank Near Western Lot Line. Evidence of Upland Runoff Erosion. (Left: 2021, Right: 2022) Photo ## & ##: Town Landing West of Boat Ramp. Shoreline Protection Installed. (Left: 2021, Right: 2022)