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HomeMy WebLinkAboutNOI 3.6.2025 1 PROJECT NARRATIVE 206 SOUTH STREET, SOUTH YARMOUTH, MA PROPOSED PIER, RAMP AND FLOAT, STONE REVETMENT RENOVATION The area subject to this Notice is land within and on the immediate shoreline of Bass River, a tidal estuary. The specific location is seaward of the mapped, mouth of the river within the zone between the navigational stone jetties forming the entrance to Bass River within Nantucket Sound. This area has been significantly altered over the past 150 years. Offshore of locus is the regularly dredged main channel for Bass River. The property is residential, containing a single- family dwelling and several out-buildings, landscaped areas, and natural areas. On the river shoreline there exists a stone revetment protecting a portion of the upland and the timber and stone remains of one of the initial breakwater jetties for Bass River. Within the specific project area there is a firm sandy bottom as the sub-tidal area extends out into the river. No aquatic vegetation seaward of the salt marsh was observed in the sub-tidal area during the survey or during the shellfish survey. A moderate quahog population was deduced beyond the MLW line in the shellfish study. Salt Marsh is clear of the project area. The proposed project is focused on the waterfront use and resiliency and involves 2 features: 1. Proposed construction of a pile supported pier, ramp and pile held float in the location shown on the attached site plan. The proposed pier is of typical design for pile- supported structures in the local area, with the seasonal ramp and pile-held float. The ramp is proposed to be aluminum of 20 ft. length to minimize the pier length. 2. Proposed reconstruction of the stone revetment with a 20 ft. extension of coir fiber sand lifts with sand cover management. The Proposed Pier - The open pile nature of the facility and specific site conditions provide for circumstances within which performance standards can be met. The open pile pier will not significantly interfere with circulation and sediment transport. This conclusion is based on empirical knowledge available from regular observations of similar structures. All river bottom areas can be viewed as viable shellfish habitat and the site does support quahogs as indicated by the shellfish study. The total bottom area occupied by the pilings is approx. 11 s.f.. We do not intend to diminish the importance of the 11 s.f., however this area value represents approximately five hundredths of one percent of the available bottom area of the on-site waterfront land area as measured out to the length of the float. The quahog population is not near shore so the square foot impact is less than 11 s.f. As a precautionary step, consistent with Yarmouth regulations it is feasible to bull rake the piling areas prior to the work and relocate any shellfish uncovered prior to the activity commencing. The proposed pier will provide a platform from which the applicants can launch a vessel rather than the disruptive activity routinely beaching boats and affecting the beach deposit. Intertidal zone and subtidal bottom impacts occur from dragging a dingy and or beaching boats to gather passengers and for general use. The proposed location is the location as where a pier previously existed. The shape of the shoreline at the specific location is a location along the line of the turn – of – the – twentieth century Bass River jetty. The stone and timber jetty formation created a significant concavity in the river shoreline and is not a natural shoreline shape feature. The shoreline shape causes a disadvantage with respect to the Town of Yarmouth rules for docks and 2 piers that limit length as measured from MHW to 80 ft. Such a length limit appears not to consider factors such as aquatic vegetation location or density, shell fish population or distance to a navigational channel. The generic, 80 ft. limit requirement, established to relate to a general level of environmental protection would apply to all cases whether a pile supported pier crosses 80 ft. of Salt Marsh, as compared with a pile-supported pier crossing over 80 ft. of a firm sandy bottom subjected to swifter currents. The environmental impacts vary significantly in these two comparative examples. The comparisons involving specific factors deserves a thorough review and consideration through the Conservation review process. Public through access along the shore is feasible below the pier. The pier end is a significant distance from the navigation channel exceeding 250 ft. where 100 ft. is the requirement. The location allows for a significant distance between existing piers with 190 ft. to the pier on the north and 257 ft. to the pier on the south where 75 ft. is the requirement. With exception of length across a sandy bottom the proposed pier far exceeds the recommended parameters in the regulations. No other opportunities exist between the three dock locations for future piers. The pier, ramp and float shall be constructed in typical manner and resemble many other facilities in the Bass River system. All pilings shall be driven. Much of the work access shall be by way of the river via small barge. The pier work involves hand carpentry techniques to fit and attach the wood framing once the piles are in place. The ramp and float shall be seasonally deployed, removed at an offsite boat ramp, and stored in the upland or offsite. Of note for the dock review is that this location is where a formerly existing pier once provided the deep-water access being requested today. The location at 206 South Street is also where a pronounced concavity exists in the shape of the river shoreline. The concaved shape is created by the manmade jetty structures constructed approximately 1900. The concave shape of the stone-lined shore is a location where the rapid current fluctuating with incoming and outgoing tides is reduced with the long-term effect of dropping sand sediment creating a shallower-sloped bottom. The location is a highly practical location for a dock facility but to reach the regulatory- required depth of water the facility must exceed the 80 ft. limit. There is no effort to achieve exorbitant depth; the goal is to meet the 3 ft. depth requirement for a modest dock facility. The result of the selected length is the pier does not extend out as far as the two docks on each side. PERFORMANCE STANDARDS SUMMARY MGL Chapt 131 – Coastal Wetland Resource Areas affected by the pier proposal are: Land Containing Shellfish, Coastal Beach, Land Under the Ocean. (The location is seaward of the mouth of the river.) Salt Marsh is present more than 100 ft. to the south and is unaffected by the proposed pier. Land Containing Shellfish – “(4) Except as provided in 310 CMR 10.34(5), any project on land containing shellfish shall not adversely affect such land or marine fisheries by a change in the productivity of such land caused by: (a) alterations of water circulation; (b) alterations in relief elevation; (c) the compacting of sediment by vehicular traffic; (d) alterations in the distribution of sediment grain size; (e) alterations in natural drainage from adjacent land; or (f) changes in 3 water quality, including, but not limited to, other than natural fluctuations in the levels of salinity, dissolved oxygen, nutrients, temperature or turbidity, or the addition of pollutants” The sand river bottom is a potential habitat for listed species. A moderate quahog population was noted in the shellfish survey. Approximately 16 sq. ft. of river bottom will be occupied by the proposed pilings. This represents approx. 5 one hundredths of one percent (0.06%) as a proportion of the sandy bottom area across the parcel waterfront out to the length of the proposed pier. Empirical evidence, available by direct observation of many open pile piers over many decades demonstrates that open pile-supported, elevated pier structures do not cause for changes in water circulation to the extent of altering the sediment structure or causing shoaling. The proposed float meets the depth requirements, does not ground at times of low water, and offers safe berthing depth; the proposed structure has no relationship to drainage of adjacent land. The common use of the pier ramp and float for boating access to navigable water constructed of appropriate materials and with common, proper practices will not introduce pollutants or affect the river water quality. Land Under the Ocean – “WHEN LAND UNDER THE OCEAN OR NEARSHORE AREAS OF LAND UNDER THE OCEAN ARE FOUND TO BE SIGNIFICANT TO THE PROTECTION OF MARINE FISHERIES, PROTECTION OF WILDLIFE HABITAT, STORM DAMAGE PREVENTION OR FLOOD CONTROL, 310 CMR 10.25(3) THROUGH (7) SHALL APPLY: (3) Improvement dredging for navigational purposes affecting land under the ocean shall be designed and carried out using the best available measures so as to minimize adverse effects on such interests caused by changes in: (a) bottom topography which will result in increased flooding or erosion caused by an increase in the height or velocity of waves impacting the shore; (b) sediment transport processes which will increase flood or erosion hazards by affecting the natural replenishment of beaches; (c) water circulation which will result in an adverse change in flushing rate, temperature, or turbidity levels; or (d) marine productivity which will result from the suspension or transport of pollutants, the smothering of bottom organisms, the accumulation of pollutants by organisms, or the destruction of marine fisheries habitat or wildlife habitat. (4) Maintenance dredging for navigational purposes affecting land under the ocean shall be designed and carried out using the best available measures so as to minimize adverse effects on such interests caused by changes in marine productivity which will result from the suspension or transport of pollutants, increases in turbidity, the smothering of bottom organisms, the accumulation of pollutants by organisms, or the destruction of marine fisheries habitat or wildlife habitat. (5) Projects not included in 310 CMR 10.25(3) or (4) which affect nearshore areas of land under the ocean shall not cause adverse effects by altering the bottom topography so as to increase storm damage or erosion of coastal beaches, coastal banks, coastal dunes, or salt marshes. (6) Projects not included in 310 CMR 10.25(3) which affect land under the ocean shall if water-dependent be designed and constructed, using best available measures, so as to minimize adverse effects, and if non-water-dependent, have no adverse effects, on marine fisheries habitat or wildlife habitat caused by: (a) alterations in water circulation; (b) destruction of eelgrass (Zostera marina) or widgeon grass (Rupia maritina) beds; (c) alterations in the distribution of sediment grain size; (d) changes in water quality, including, but not limited 4 to, other than natural fluctuations in the level of dissolved oxygen, temperature or turbidity, or the addition of pollutants; or (e) alterations of shallow submerged lands with high densities of polychaetes, mollusks or macrophytic algae.” The summary of performance standards for Land Under the Ocean is included to draw attention to a certain contrast between projects that are evident. The common practice of improvement and maintenance dredging is outlined as a direct focus in the regulations. Dredging work requirements are outlined as a priority in this section because dredging is so common and provides the greatest proportion of alterations to Land Under the Ocean on the order of acres within Bass River. Both dredging practices occur in this immediate area on a large scale with maintenance dredging being most common, involving the Bass River channels and mooring basins. All the standards for Land Containing Shellfish apply to Land Under the Ocean. However, of important note is the comparative scale of the relatively minor bottom sediment alteration by the installation and presence of 21 10-inch diameter pilings compared to many typical dredging operations. For this reason and the outline above for Land Containing Shellfish we can conclude that the proposed pile supported structure, ramp, and pile -held float will not significantly adversely impact Land Under the Ocean. The Bass River is a known catadromous and anadromous fishery route but the banks of the river or the channels are not being altered. Coastal Beach – “WHEN A COASTAL BEACH IS DETERMINED TO BE SIGNIFICANT TO STORM DAMAGE PREVENTION, FLOOD CONTROL, OR PROTECTION OF WILDLIFE HABITAT, 310 CMR 10.27(3) THROUGH (7) SHALL APPLY: (3) Any project on a coastal beach, except any project permitted under 310 CMR 10.30(3)(a), shall not have an adverse effect by increasing erosion, decreasing the volume or changing the form of any such coastal beach or an adjacent or downdrift coastal beach.” The Coastal beach is the span of sandy mud between the MHW line at the stone revetment and the MLW tide line. The land area involved is approximately 60 sq. ft. that will be overlain by the elevated, 4 ft. width pier deck. There are 2 pilings (1.5 s.f.) proposed within the Coastal Beach. The 1.5 s.f. value when placed in context and comparison to a range of approved coastal projects within Coastal Beaches allows for a conclusion of no significant adverse impact. Land Subject to Coastal Storm Flow (LSCSF) – The proposed structure is designed to exist within a tidal water body with incident storm action and is therefore, incidentally appropriate for a flood zone. There are no DEP performance standards yet for LSCSF. REVETMENT REPLACEMENT – The specific project area involving the revetment reconstruction is a Coastal Bank along the east segment of the property coastline currently armored with a stone revetment. For varying reasons, the revetment has had stability trouble, partially due to age, composition, lack of filter fabric, strong storm action and technical shortcomings with techniques for stone setting necessary for optimal stability in the specific exposed environment. The revetment and associated stone jetty that forms the manmade alignment of the concaved shoreline is licensed by Chapt. 91 License number 4727. Access for revetment work is practical by crossing the upland on site. The work activity shall be limited to the specific section of revetment along the river with a 20 ft. extension of coir fiber, 5 sand filled lifts. The work effort shall be organized, staged in the existing lawn area, with much of the stone work occurring from the side and from the top. As a renovation of an existing stone revetment with the objective of bank stability improvement the project serves the interests of storm damage and flood control and is consistent with performance standards for 310 CMR 10.30 of the Wetland Regulations and the Yarmouth Wetland Bylaw. An existing set of stone slab steps will be re-established on the south end in a location where slab steps currently exist. Coastal resource areas directly affected include: • Coastal bank • Coastal beach • Land subject to coastal storm flow Nearby coastal resources include: • Land under the ocean (to the south seaward of the low tide line) • Land containing shellfish (farther out in subtidal areas) • Salt marsh The nearby resource areas will be unaffected by the work with adherence to appropriate work practices. PERFORMANCE STANDARDS The project can be found to meet the performance standards for the resource areas potentially affected as follows: The project may fit into the regulations as a “Limited project under 310CMR 10.24 however the NOI will discuss the project relationship to the performance standards independently. Coastal Banks -Sediment Source Banks (310 CMR 10.30) “WHEN A COASTAL BANK IS DETERMINED TO BE SIGNIFICANT TO STORM DAMAGE PREVENTION AND FLOOD CONTROL BECAUSE IT SUPPLIES SEDIMENT TO COASTAL BEACHES, COASTAL DUNES OR BARRIER BEACHES…..” “No new bulkhead, revetment, seawall, groin or other coastal engineering structure shall be permitted on such a coastal bank except that such a coastal engineering structure shall be permitted when required to prevent storm damage to buildings constructed prior to the effective date…” • The CES at the site is not new. Restoration and improvement with up-to – date stone setting technique and geotextile are logical necessary activities that will improve the bank and related CES as a vertical storm buffer. The relationship to storm damage prevention and flood control has value and significance for related standards for Land Subject to Coastal Storm Flow and for Coastal Beaches. Best Available Measures (310 CMR 10.27 & 10.30) 6 The stone revetment system along this shoreline may be deemed a best available measure having been in place for many decades or more. Sand nourishment can be part of the management activity, with sand added over the coir sand lifts periodically. Given the sediment in active movement are the sediments from earlier dredging actions there is no significant need to add large amounts of sediment near the dredged navigation channel only to have the sediment removed. Sand cover practice for the coir lifts is sufficient. The existing harbor jetties as well as the older earlier jetty remnant provide a significant alteration and stabilizing function to the sediment system in this reach of the waterway. Vertical Storm Buffer (10.30) With the CES in place, the bank is functioning as a vertical storm buffer. “WHEN A COASTAL BANK IS DETERMINED TO BE SIGNIFICANT TO STORM DAMAGE PREVENTION OR FLOOD CONTROL BECAUSE IT IS A VERTICAL STORM BUFFER TO STORM WATERS…..” With respect to the vertical storm-buffer significance of this bank, the proposed project meets the performance standard because it improves bank stability as a storm buffer. “Bulkheads, revetments seawalls, groins or other coastal engineering structures may be permitted on such a coastal bank except when such bank is significant to storm damage prevention and flood control because it supplies sediment to coastal beaches, coastal dunes and barrier beaches…” The reasoning offered in the above section for sediment source banks partially rebuts the presumption of significance and identifies the lower significance of this bank for the listed sediment-based storm-damage prevention interest. Therefore, improvement to the erosion measures is appropriate. Coastal Beaches- 310 CMR 10.27 - Regulations contained in 310 CMR 10.27 provide an exception relating to 310 CMR 10.30(3)(a) for erosion-management applications that use best available measures to minimize adverse impacts to coastal beaches. The regulations recognize the fact that erosion measures are at times necessary and should have effects minimized but cannot be avoided completely. The work area shall be limited and temporarily affected with anticipated recovery over several tide cycles following completion. The replacement project causes for no encroachment seaward of the existing revetment. The bank stabilizing project activity furthers the interest of storm damage prevention and will not cause for any added detrimental effects to the local environment. Yarmouth Regulations: Proposed Pier – A review of the Yarmouth regulations for piers shows consistency with all regulations with exception of: • # 10, the 80 ft. length limit measured from MHW. The proposed pier, ramp and float require a 48 ft. waiver. The proposed location is where a pier previously existed. The shape of the shoreline at the specific location is forced along the line of the turn – of – the – twentieth century Bass River jetty. The stone and timber jetty formation created a significant concavity in the river shoreline and is not a natural shoreline shape feature. The shoreline shape causes a disadvantage, specific to this applicant with respect to the Town of Yarmouth rules for docks and piers that limit length as measured from MHW to 7 80 ft. Such a length limit as written does not include factors such as the presence of aquatic vegetation density, sediment texture, shellfish population or distance to a navigational channel. The 80 ft. limit requirement, established to foster general level of environmental protection does not include consideration whether a pile supported pier crosses 80 ft. of Salt Marsh, or if navigating to the facility crosses other vegetated shallows as compared with a pile-supported pier crossing over 80 ft. of a firm sandy bottom with direct access to a dredge channel. Factors for consideration are: 1. The location within the waterway is seaward of the; “mouth of the river” as DEP defines it. 2. There is direct access to deep water with no vegetated shallows. Vegetation of a sponge Codium appears to exist but not in shallow water. 3. The large distance from other structures, 190 ft. to the north and 247 ft. to the south. 4. No logical possibility of any other docks reducing those separation distances in the future 5. The significantly large distance of 265 ft. to the edge of the navigation channel with deep water between. 6. The manmade breakwater waterway shape alteration causing for the shore shape disadvantage. 7. The low density of aquatic vegetation. Codium appears to predominate. 8. Shellfish habitat affected by the requested waiver is approx. 7 s.f.; Regulations encourage bull raking to relay the animals out of conflict. 9. Firm, sandy bottom sediment with no turbidity resulting from the river current having carried all fines away. The inclusion of these factors that relate to comparisons, for example, the case where an 80 ft. pier is allowed by right across 75 ft. of salt marsh in a location where a motorized vessel might also traverse hundreds of feet of vegetated shallow water to transit to a from indicates that the project under review in this application deserves a fair and critical evaluation, and consideration through the Conservation review process. • With respect to regulation 12 d. The location of the pier is accompanied by a supportive communication from the owner of 204 South Street, the adjacent property owner. Coastal beach / Tidal Flats The short segment of elevated pier and 2 pilings within the intertidal beach by virtue of the small scope of alteration with not: (a) Affect the ability of the waves to remove sand from the beach or tidal flat; (b) Disturb the vegetative cover, if any, to destabilize the beach or tidal flat as there is none. (c) Cause any modification of the beach or downdrift beach that would increase the potential for storm or flood damage. (d) Interfere with the natural movement of the beach or tidal flat; (e) Causing artificial removal of sand from the beach or downdrift beach; 8 Land Containing Shellfish- The shellfish report indicates quahogs are present as a moderate population in the area off shore and that is not surprising given the fact that the conditions are favorable. The pier extension is in the deeper water where there is the the greatest separation of the pier deck to the bottom, minimizing shading and will affect approx. 5 s.f. of sandy bottom habitat. To arrive at a reasonable interpretation of the scale of impact to Land Containing Shellfish, the approx. 7 s.f. occupied by pilings where quahogs exist represents less than two / one hundredths of an acre. For context, this very small value may be compared to the common and recent dredging within Bass River undertaken by both Yarmouth and Dennis municipalities that involves whole numbers of acres. There is no shellfish removal prior to these large-scale dredging actions. This applicant is agreeable to bull rake the piling zones prior to performing work. The piles will not by virtue of direct observations of other similar structures: (a) alter water circulation; (b) alter relief elevation; (c) the compact sediment by vehicular traffic; (d) alter the distribution of sediment grain size; (e) alter natural drainage from adjacent land because it is in the river. (f) change the water quality, including, but not limited to, other than natural fluctuations in the levels of salinity, dissolved oxygen, temperature or turbidity, or the addition of pollutants. Land Subject to Coastal Storm Flow - The proposed pier, ramp and float are within Bass River and the pier partially overlies a stone revetment, both terrain types, not of an upland character. Appropriate design for a tidal, coastal pier considers hydraulic behavior and relies upon common techniques for maintaining “open” frame to allow flood waters, or in this case, tidal waters to pass through. Further elaboration is available relative to CLSF upon request. Stone Revetment Project Portion The summary relating to Coastal Banks contained in the Yarmouth Regulations appear to mirror those discussed previously under 310 CMR 10. 30. Please refer to the section above relating to the proposed revetment work activity. The stone revetment exists. The re-building of the revetment does not expand its projection in the waterway, allowing the upland to absorb all impacts from the renovation. Severe coastal storm forces that have not been realized since the mid 1950’s have potential to scatter the small rip rap stone currently comprising the revetment. Acting now to properly renovate the revetment will serve to improve the bank and a vertical storm buffer and to also prevent the deleterious effects of uncontrolled scattering of the darker granite non-native stone into the intertidal zone from severe storm over wash. Renovation of the existing revetment in the approximate same projection but with improved techniques and material quality is best evaluated with interest in minimizing long term adverse impact. A review of the proposed renovation allows for a favorable conclusion that long term adverse impact is reduced.