Sent via electronic mail to: samuel.bell@usace.army.mil
July 18, 2025
Mr. Samuel Bell
U.S. Army Corps of Engineers – New England District
696 Virginia Road
Concord, MA 01742-2751
RE: Providence River and Harbor Federal Navigation Project Rhode Island Dredged Material Management Plan and Environmental Assessment
Dear Mr. Bell,
Save The Bay, on behalf of its members and supporters, is pleased to use this opportunity to submit public comments in response to the Providence River and Harbor Federal Navigation Project – Dredged Material Management Plan and Environmental Assessment (FNP DMMP-EA) issued by the U.S. Army Corps of Engineers (ACOE).
Save The Bay – Narragansett Bay is a member supported environmental advocacy non-profit 501(c)(3) with offices in Providence, Newport and Westerly, RI. Our mission of protecting and improving Narragansett Bay is accomplished through many aspects of our work including advocacy, habitat restoration and adaptation, and on-the-water experiential education for students, summer campers, and the public at large. Having advocated for the Bay for over 50 years, and with its main office at Fields Point in Providence for 18 years, Save The Bay has seen significant improvements to the water quality of the Providence River, Narragansett Bay, and the surrounding watersheds. Especially in the area of the Providence River where we are located, the water and waterfront have changed significantly, becoming a place where citizens once again feel comfortable accessing the water to safely boat, fish, swim, and even now shellfish for the first time in over 80 years. These improvements are no small feat and are the result of decades of intense advocacy, strengthened environmental regulations regarding water and coastal land use, and stormwater infrastructure upgrades by many parties.
As vessel operators in the Providence River, and proponents of a growing blue economy heavily reliant upon the ability for vessels to safely navigate Rhode Island’s waters, Save The Bay appreciates the need for dredging in the Providence River and Harbor Federal Navigation Project area to support a federally maintained channel to an important port and the U.S. Army Corps’ obligation to maintain that channel. While Save The Bay supports the proper and safe disposal of the resulting unsuitable dredged materials (through the use of Confined Aquatic Disposal [CAD] cells), we believe that the project, as designed, does not adequately address potential harm to humans, and does not provide flexibility to ensure optimal options for the beneficial use of suitable material excavated during Cycle Two of the project.
Save The Bay is uniquely suited to provide substantive comment as we; 1) represent an interstate coalition of members and supporters who are citizens of the Bay watershed, with a shared vision of clean, fishable, swimmable habitats, and 2) are located on Fields Point, in the Providence River, abutting the waters in question, and are both users of the Providence River with year-round vessel operations and seasonal direct use of the water bodies to be affected by the work in question. Our site on the Providence River also serves as a seasonal public access point for fishing, boating, kayaking and walking the shoreline to learn about and enjoy Narragansett Bay. It is with this position in mind that Save The Bay offers the following comments and recommendations.
In the sections below, we offer recommendations for:
1) Modifying the seasonal restrictions, to take human use into consideration
2) Increased turbidity mitigation efforts and the inclusion of turbidity monitoring
3) Modifications to CAD cells at Edgewood Shoals to reduce vessel traffic obstruction and contaminated sediment interaction
4) Added flexibility to the DMMP-EA allowing for the assessment of future dredging and CAD cell needs and the identification of alternate options for beneficial use of suitable material
5) Considering where and why shellfish, particularly quahog, encountered during dredging and CAD cell construction, are being relocated
Greater Protection For Bay Users: Seasonal Limitations on the Construction and Excavation of CAD Cells
Save The Bay urges the ACOE to implement seasonal restrictions on the construction and excavation of the proposed CAD cells in Edgewood Shoals to protect not just biota, but also Bay users from potential harms associated with the work proposed, including exposure to contaminated suspended sediments resulting from the work. The ACOE states that the use of the proposed CAD cells is to dispose of contaminated material that is unsuitable for open-water disposal. Exposure to any contaminated fill in suspension during construction and excavation can be significantly reduced with adherence to seasonal restrictions on the work.
The proposed locations of the Edgewood Shoals North (ESN) and Edgewood Shoals South (ESS) CAD cells directly abut waterways and coastal properties utilized both commercially by marinas, yacht clubs, and businesses, and recreationally by local residents. At Save The Bay, located on the coast directly north of the Port Edgewood Basin (PEB), we routinely have students and campers interacting with the water of the Providence River through exploration of the rocky shoreline on our property or collecting water samples from our docks. In addition, our facility is used frequently by members of the public as a public access point for bathing, boating, and recreational and subsistence fishing. Multiple marinas and yacht clubs are also located along the shore abutting PEB and the proposed CAD cell locations, with the potential for users interacting with the waters of the Providence River. Edgewood Yacht Club (EYC), home to Edgewood Sailing School, offers school-year and summer sailing programs which include the near certainty of individuals entering the waters of the Providence River. Finally, dozens of residential properties in the city of Cranston are located along the western shore of the waters in question, with the potential for residents engaged in direct contact with the Providence River. Any of these direct human interactions with the water provide the potential for exposure to contaminated sediments suspended during the creation of CAD cells or the disposal of contaminated unsuitable fill during material placement within the CAD cells.
While Section 10 of the DMMP-EA “Actions to Minimize Environmental Consequences” lists nine specific actions to minimize potential harms to affected habitats and biota, which Save The Bay appreciates, there are no proposed actions listed to minimize the potential for harm to humans. As it pertains to the CAD cell work in Edgewood Shoals, the only listed time of year restrictions on work are the prohibition of dredging and material placement during the months of February, March, and April to protect winter flounder (Pseudopleuronectes americanus) spawning habitat. However, federal regulation 40 CFR § 230.10 (c)(1) requires that the effects of discharge “on human health or welfare” should be considered. It is for these reasons that Save The Bay strongly urges the ACOE to require that the schedule of the excavation and construction of CAD cells and the disposal of contaminated unsuitable fill within the CAD cells in Edgewood Shoals also include, to the maximum extent possible, prohibitions from mid-June through Labor Day. This would restrict these activities to a time of year with a reduced human use, thus reducing potential human exposure to contaminated suspended sediments resulting from the work.
Greater Protection For Bay Users: Recommendation for Turbidity Mitigation Measures and Monitoring
Save The Bay urges the addition of multiple measures during dredging operations and the filling of the CAD cells, specifically ESN and ESS cells, in order to mitigate the resuspension of sediment into the water column, especially in the areas proximal to human use, and to identify when high levels of suspended sediment are being generated. These should include the use of silt screens/curtains around CAD cell filling, turbidity monitoring, and turbidity standards with protocol to follow if monitoring detects exceedances.
The DMMP-EA details the harms caused to benthic biota from increased turbidity, which include increased mortality, decreased growth, decreased filtering/feeding, and increased gill abrasion and respiratory damage. Increasing the potential for environmental harm, and negative human interactions, is the certainty that many of the surface sediments are also contaminated with legacy pollutants. However, the ACOE has proposed little to no mitigation strategies to ensure the least amount of resuspension of these sediments into the Bay, or to quantitatively confirm exactly how much resuspension is occurring.
The ACOE has explained that during dredging activities, a clamshell style dredge, or environmental bucket dredge, will be used in order to minimize the resuspension of sediments during the dredging portion of the work proposed. This should result in minimal, localized, and short-term turbidity disturbance to affected areas. Additionally, the nature of dredging operations, the depth at which they take place, and the location of this work (being further from areas of direct human contact of the water) make it difficult or unnecessary to deploy physical barriers or employ further measures to mitigate suspended sediment transport during the dredging portion of the project.
However, in our review of the DMMP-EA, Save The Bay did not find reference to any proposed turbidity mitigation efforts to be utilized during the CAD cell filling portion of the work. Specifically, as it pertains to ESN and ESS CAD cells, the portion of work which holds the potential for large scale resuspension of both suitable and contaminated unsuitable materials and their ensuing downstream transport in an area of increased human interaction with the water, no mention is made of suspended particulate or turbidity mitigation. Determining the impacts of turbidity, including whether increased turbidity will impact water quality standards or cause harm to environmental values, are required factual determinations under federal regulations. See 40 CFR § 230.11 (c).
In a similar dredging project in New Bedford, MA, the US Environmental Protection Agency (EPA), required turbidity controls intended to reduce sediment migration outside the area of work.1 Although Save The Bay acknowledges that New Bedford Harbor is a superfund site, mandating silt screens/curtains around CAD cell filling activities to reduce sediment transport is similarly important for the Providence River and Harbor FNP where contaminated material has been deemed unsuitable for open water discharge. Save The Bay urges the ACOE to make the same requirement that silt screens/curtains be deployed around the perimeter of work during any CAD cell filling in the Edgewood Shoals work area; an area with known and robust human interaction and use.
Finally, Save The Bay did not find reference to any proposed turbidity monitoring, or any turbidity standards guiding such monitoring, during any aspect of the work. Without quantitative monitoring in place through the duration of work, it would be impossible to determine if the extent of the resuspension, and ensuing downstream transport, of sediment, contaminated or not, is in fact minimal. Similar to other projects of this nature and scale, as exemplified by the requirements in the aforementioned 2014 EPA letter regarding New Bedford Harbor dredging activities, Save The Bay urges the ACOE to require mandatory turbidity monitoring during all aspects of dredging and CAD cell filling (at the location of work, downstream of the work, and upstream of the work as a reference location), to set and adhere to clearly outlined turbidity standards and allowances for increases, and to lay out clear steps to be taken when results of monitoring exceed set standards.
Reduced Vessel Traffic Conflicts and Contaminated Sediment Disturbance: Proposed Relocation of ESN and ESS CAD Cells
Save The Bay urges the ACOE to relocate the proposed ENS and ESS CAD cells to the east to reduce vessel traffic conflicts, increase the buffer between construction and an active mooring field, and avoid excavation activities in an area with elevated sediment contamination.
In addition to increased seasonal human interactions with the water, Save The Bay, together with Ocean State Boat Basin, Edgewood Yacht Club, and Rhode Island Yacht Club, have regular vessel traffic transiting Edgewood Shoals area, especially through the Port Edgewood Channel (PEC). Impacts to “resources which support recreational activities” must be evaluated and considered, as well as the timing of work in order to “avoid the seasons or periods when human recreational activity associated with the aquatic site is most important.” 40 CFR § 230.52 (b); 40 CFR § 230.76 (c). While Save The Bay’s vessel traffic has the potential to be year-round, our operations, in addition to those of the aforementioned boating centers, experience drastically increased usage of these waters during the spring, summer, and fall. The proposed location of ESN and ESS CAD cells is directly under the PEC which connects PEB, and Save The Bay’s dockage, to the Sabin Point Reach and Bullock Point Reach sections of the Providence River Channel. This channel is routinely utilized by vessels departing and returning to their dockage, mooring, or anchorage at the aforementioned boating center. The proposed locations for CAD cells would result in the intermittent blocking of personal and commercial vessel traffic by any vessels engaged in work during the excavation phase for the construction of
CAD cells or the material placement into the CAD cell during dredging operations. Additionally, the ESN CAD cell location extends beyond PEC to the west, seemingly unnecessarily directly abutting EYC’s active mooring field. Finally, as indicated in Figure 4-7 (pg. 44) of the DMMP-EA, the surface sediments of the PEC, which runs directly through the proposed CAD cell locations, are deemed as unsuitable sediments, containing “moderate to high levels of most analyzed COCs,” ”concentrations of metals, PAHs, total PCBs, and multiple pesticides above the effects-range low sediment quality screening guideline (USACE, 2022b),” and ”multiple metals, PCBs, and pesticides above the effects-range median sediment quality screening guideline,” while the surrounding surface sediments of Edgewood Shoals to the east are not.2
For these reasons, Save The Bay urges the ACOE to relocate the proposed ENS and ESS CAD cells to the east, no longer overlapping with the the PEC, to reduce potential disruption of vessel traffic, increase the distance between CAD cell construction/filling and the EYC mooring field, and avoid digging in the PEC whose sediment contains documented higher surface level contaminants. This relocation would not only reduce vessel traffic conflicts, but importantly, would provide added human health and ecosystem protections in this actively used area of the Providence River.
Including Flexibility: Reassessing Future Dredging Needs and Potential Beneficial Use Options
Save The Bay encourages the ACOE to incorporate the ability to reevaluate future dredging needs and potential beneficial uses within this permit cycle, closer to execution of Cycle Two. Retaining flexibility to identify alternatives twenty years from now provides an opportunity to reassess the scope of accumulated sediments and associated dredging needs prior to Cycle Two, and could provide the opportunity to identify less expensive, and possibly more environmentally sound, beneficial use options.
The basis for the choice of Alternative 2A as the best option for the project is that it is the lowest cost option for the ACOE’s execution of the project and the resulting beneficial use of suitable materials excavated. However, these projects do not occur in a vacuum, with many factors affecting the cost of every option. In this instance, these factors could include unpredictable weather/climate with potentially minimal shoaling requiring less dredging and CAD cell capacity need, or projects newly approved to receive beneficial use materials close to dredging operations. While Alternative 2A may, at the moment, be the lowest cost option investigated by the ACOE, there may be other options available in 20 years that present less expensive, and ideally more environmentally sound options during Cycle Two.
Although 20-year timeframes for dredging cycles in FNPs, as a part of ACOE’s Long Term Management Strategy (LTMS), have long-term planning benefits, those benefits should not outweigh potential impacts to the Bay’s coastal and estuarine ecosystems. With changing climate, rising water temperatures, sea-level rise, and increased storm intensity impacting every aspect of Narragansett Bay, it is imprudent for the ACOE to lock into construction and excavation plans for the Bay two decades from now, without an opportunity to review and evaluate conditions at that time. Undeniable changes are occurring in Narragansett Bay that may greatly impact sediment and nutrient needs crucial to maintain a healthy and productive ecosystem. Save The Bay, and other Bay users, deserve an opportunity to understand those impacts through the lens of conditions in real time, rather than imagining them for two decades from now.
Based on the DMMP-EA, the ACOE is proposing to dispose of approximately 3,581,000 CY of suitable sediment offshore at the Rhode Island Sound Disposal Site (RISDS), 885,000 CY during Cycle One and 2,696,000 CY during Cycle Two. However, sediments in coastal estuaries are an integral resource for habitat health, creation, and maintenance. Fine-grain sediments, like those found in deeper portions and more northern portions of the Bay, carry with them naturally occurring nutrients, a requirement for photosynthetic production, and are a key building block for sandy shore and salt marsh habitats. In relatively low sediment input systems such as Narragansett Bay, with relatively low accretion rates observed at marshes and beaches in the Bay, Save The Bay believes it is imperative to retain as much suitable material uncovered during CAD cell excavation as possible within the estuary, and permanently remove as little as possible from the system through offshore disposal at the RISDS. Providing flexibility in a final proposal would create the ability to identify future beneficial use options that retain as much sediment as possible within the Bay watershed.
Save The Bay urges the ACOE to include language in a final approved proposal to allow for the reexamination of 1) the need for dredging prior to the start of Cycle Two, 2) the need for a second CAD cell to be constructed during Cycle Two, and 3) the available options for the beneficial use of suitable material, especially should a second CAD cell be needed during Cycle Two, which would hopefully result in more suitable fill remaining in the Providence River and Narragansett Bay watershed than is currently proposed, decreasing the amount being disposed of offshore in the RISDS.
Careful Consideration Regarding the Relocation of Shellfish/Quahog Removed During Work
Save The Bay was unable to identify a clearly laid out plan in the DMMP-EA, besides a line item in the budget, for the relocation of shellfish encountered during dredging and CAD cell construction. In accordance with federal regulations, ACOE must evaluate the effects of potential interference with “the reproductive success of recreational and commercially important aquatic species” including Narragansett Bay’s important quahog fishery. 40 CFR § 230.51 (b). Therefore, we encourage the ACOE to carefully consider the relocation of any shellfish, but especially hardshell clam, a.k.a. quahog (Mercenaria mercenaria), encountered and removed during all work. Relocation should consider sediment type, water quality parameters, and existing population density at proposed locations elsewhere in the Providence River for transplant, and the short- and long-term impacts of relocating any quahogs out of the portion of the Providence River currently closed to shellfishing.
Rhode Island has a rich history of maintaining an active shellfishing industry, particularly a quahog fishery, however, in recent decades the number of commercial quahoggers and the amount of quahog landed has decreased since the most recent peak in landings in the 1980s. Currently the commercial quahog fishery is represented by fewer than 200 commercial quahoggers, while fewer than 100 of those are full-time. This decrease corresponds with the decreases in total landings during the same time period, with “[t]he annual harvest in 2023 of about 359,000 meat pounds [being] less than half of what it was a decade ago and less than a tenth of harvests during the last big peak for the industry in the early 1980s.”3 The 2024 Rhode Island Special Legislative Commission Report documented that the “… abundance of quahogs in Narragansett Bay proper (which includes the Upper Bay, Mt. Hope Bay, and the Sakonnet River) and Greenwich Bay have been relatively consistent at 1-3 quahogs/m2for the past 30 years (1993 to 2022).”4 However, during that time “[q]uahog abundance in the lower Providence River increased to approximately 6-10 quahogs /m2 during 2015 to 2022 as compared to approximately 5 quahogs per m2 during 1993 to 2013.”5 While these numbers represent a density of quahog in the Providence River of two to ten times greater than Narragansett Bay, RI DEM data cited by the ACOE in Figure 4-15 (DMMP-EA pg. 69) indicate that mean quahog density in and around the areas of proposed work ranges up to a maximum of 53.8 quahog/m2, a density of 18 to 53 times greater than that of Narragansett Bay.6
The life cycle of the M. mercenaria begins with a 6-20 day period, an almost identical timeline to the soft shell clam (Mya arenaria), depending on water temperatures, where a new individual exists as a free-floating egg then swimming trochophore larval stage, and it is at the end of this larval stage that an individual clam settles out of the water column and into the substrate.7 Given the southward flow of water in the bay, and the roughly 26-day mean flushing period of the Bay, there is the ability for an adult quahog spawning in the Providence River or upper Narragansett Bay to seed much of the lower bay with offspring.8 This broadcast spawning, along with an increased population density, and generally older and larger clams in this portion of the river (from over 75 years of not being harvested), mean that the population of spawning quahog in the Providence River act as a “broodstock,” and account for approximately 38% of all quahog larvae recruitment in Narragansett Bay.9 Relocation of a portion of these individuals from the area currently restricted from harvest could result in a decline in the quahog larval recruitment, a subsequent decline in the adult population, and an exacerbated decline to the quahog fishery. We can also assume that the higher quahog population density in the Providence River and related significance as broodstock to be the case for other shellfish species in the same area (despite the lack of associated data for those other shellfish species).
In order for the ACOE to satisfy the obligation required by 40 CFR § 230.51 (b) requiring consideration of impacts to the “reproductive success” of important commercial and recreational species, and to sustain robust shellfish populations in the bay, and, importantly, maintain a viable quahog fishery into the future, Save The Bay is requesting the inclusion of explicit language in a final proposal as to how the ACOE will determine where it intends to relocate any shellfish encountered during dredging and CAD cell construction. Our recommendation for the choice of relocation would be to identify locations based in science and through conversation with the RI DEM – Division of Marine Fisheries and all other concerned and affected stakeholders. We ask that these conversations and proposed locations are based on the most current research, and take into account sediment type, water quality parameters, and population density.
In summary, Save The Bay appreciates the need for dredging in the Providence River and Harbor Federal Navigation Project area to support the federally maintained channel to an important port and the U.S. Army Corps’ obligation to maintain that channel. However, we feel that the DMMP-EA as proposed falls short of meeting its obligations to protect the habitat and users of the Bay. Therefore, Save The Bay is opposed to the Providence River and Harbor Federal Navigation Project Rhode Island Dredged Material Management Plan and Environmental Assessment as currently proposed, and urges the ACOE to include the above listed recommendations; specifically:
1) Modify the seasonal restrictions, to take human use into consideration
2) Increase turbidity mitigation efforts and implement turbidity monitoring
3) Modify the ESN and ESS CAD cells to reduce vessel traffic obstruction and contaminated sediment interaction
4) Add flexibility to the DMMP-EA to allow for the assessment of future dredging and CAD cell needs and the identification of alternate options for beneficial use of suitable material
5) Consider where and why shellfish, particularly quahog, encountered during dredging and CAD cell construction are being relocated
We are available to discuss these recommendations, or other reasonable alternatives that meet the intended goals described above. Thank you for your consideration.
Sincerely,
Capt. Chris Dodge
Narragansett Baykeeper – Save the Bay
100 Save the Bay Dr.
Providence, RI 02905
(401) 272-3540 x116
cdodge@savebay.org
cc:
Linda Perri – Washington Park Association
Jackie Cambio – Commodore: Edgewood Yacht Club
Eric Schneider – Principal Marine Fisheries Biologist: RI DEM Division of Marine Fisheries Jeffrey Willis – Executive Director: CRMC
1 See Craffey, P. (EPA) “RE: New Bedford Harbor State Enhanced Remedy” 2014 correspondence to Lombardo, G.: https://19january2021snapshot.epa.gov/sites/static/files/2014-12/documents/569429.pdf (accessed 15 July 2025).
2 See U.S. Army Corps of Engineers’ Providence River and Harbor Federal Navigation Project – Dredged Material Management Plan and Environmental Assessment, Figure 4-7 at 44.
3 Special Legislative Commission to Study and Provide Recommendations on the Issues Relating to the Reduced Catch of Quahogs in Narragansett Bay – Final Report (2024);
https://www.rilegislature.gov/commissions/QJC/commdocs/05-31-2024-Quahog%20Commission%20Final%20Report%2 0PDF%20Signed%20by%20Co-Chairs.pdf (accessed 14 July 2025).
4Id.
5Id.
6 See U.S. Army Corps of Engineers’ Providence River and Harbor Federal Navigation Project – Dredged Material Management Plan and Environmental Assessment, Figure 4-15 at 69.
7 Eversole, Arnold G. (1987). Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (South Atlantic ), Biological Report 82 (11.75): 1-33.
8 Pilson, Michael E.Q. (1985). On the residence time of water in Narragansett Bay. Estuaries 8:2–14. 9 M. Connor McManus. RI DEM Quahog Commission – Science and Management of the Narragansett Bay Quahog: A Review (2023):
https://www.rilegislature.gov/commissions/QJC/commdocs/10-24-2023—M.%20Conor%20McManus%20Quahog%20Co mmission%20PDF.pdf (accessed 14 July 2025).