Drainville, Marc

Marc is a principal with GHD based in Hyannis, Massachusetts. He is a professional engineer and board-certified environmental engineer. He specializes in advanced wastewater treatment, collection system and planning projects.

Titles from this speaker

Description: Adapting Collection System Infrastructure to Changing Flood Vulnerabilities - New...

Adapting Collection System Infrastructure to Changing Flood Vulnerabilities - New England Case Studies

Abstract

Collection systems and treatment facilities serve as an important environmental line of defense against wastewater contamination of groundwater and coastal embayments. With more intense and frequent storm events and rising sea levels, many communities are facing an increased risk to critical wastewater infrastructure from flooding and storm damage affecting critical wastewater infrastructure (Figure 1). This presentation will use case studies for collection system infrastructure along multiple types of waterbodies to discuss flood resilience measures being evaluated and implemented in Southeastern Massachusetts. The case studies discuss collection system infrastructure along: -Complex coastal estuarine shorelines -Open ocean -Tidally influenced coastal ponds -Inland river flood plains The presentation will also focus on how these communities are incorporating accommodations for projected changes in storm intensity and frequency into flood resilience evaluation, design and construction. A brief description of each case study is summarized below. Town of Wareham, MA (complex coastal estuarine shorelines) - The Town of Wareham is a coastal community with over 54 miles of coastline. Hydraulic constrictions caused by the complex coastal estuarine system results in high anticipated flood levels, up to 21 feet above mean sea level. The Town recently completed a 'Risk and Vulnerability Assessment', which provided them with a valuable tool to quantify the anticipated costs borne to the Town and its citizens if any vulnerable pump station failed during a 100-year storm event. The assessment provided the Town with a road map and prioritization strategy on which of its many competing coastal resilience wastewater infrastructure needs to address first. Building on the findings of the Assessment, the Town has proceeded with the design of coastal resilience mitigation measures for three pump stations which were among the highest priority stations because they serve critical infrastructure (a hospital, fire department and police department). Coastal resilience measures incorporated into the design include the use of flood planks, structural reinforcement of existing structures (Figure 2), sealing potential water entry points and installation of emergency bypass connections (Figure 3). The construction of pump station bypass connections has been completed and relocation and elevation of emergency generators is in progress. Additionally, following multiple Nor'easter storms in 2018 that exceeded the regional 40-year flood stage record, the Town conducted an evaluation of the impact of anticipated increased rainfall from more frequent and intense storms on the infiltration/inflow entering its collection system. The repetitive, consecutive nature of the 2018 storms elevated the groundwater table, producing more head pressure in the gravity collection system which dramatically increased infiltration rates entering the collection system and being conveyed to the Wareham Water Pollution Control Facility. The Town has successfully constructed the retrofit measures recommended by the I/I projections evaluation (Figure 4). Town of Oak Bluffs, MA (infrastructure exposed to the open ocean) -The Town of Oak Bluffs is a coastal community on the island of Martha's Vineyard. Its three vulnerable stations serve over 90% of the Town's sewered population, including many residences and the Town's primary commercial district (Figure 5). The Town recently completed the construction of mitigation measures to increase the coastal resilience of the stations through installation of a new emergency generator on a raised platform (Figure 6) and relocation of critical pump station equipment outside of the flood zone. The Town is currently in final design of an elevated electrical building superstructure designed to withstand anticipated flood conditions, with accommodations for the impacts of climate change through its design life. Town of Chatham, MA (tidally influenced coastal pond) - The Town of Chatham is a coastal community on Cape Cod. One of the Town's wet pit/dry pit pumping stations (Mill Pond) is located at the base of a tidally influenced coastal pond; updated FEMA flood maps show that the location is vulnerable to storm surges and flood events. During the Mill Pond Pumping Station Upgrade design, multiple flood protection measures were incorporated to increase the coastal resilience of the station. These measures include the establishment of a design flood elevation for the project which incorporates anticipated effects of sea level rise, installation of hydrophilic water stops and a flood proof entry door with stop blocks to provide flood mitigation measures (Figure 7). Town of Uxbridge, MA (inland river flood plain) — The Town of Uxbridge is an inland community in Central Massachusetts. Since construction of its centralized collection system the Blackstone River flood plain maps been revised and recent storm events have indicated that the Town's largest pump station is now vulnerable to the 100 year flood storm. During one storm event water was observed entering the station's wet well through conduits and rising within a couple inches of the top of the entrance tube (Figure 8). Additionally, the existing generator room was flooded, rendering equipment in the room inoperable during the storm event. The Town has finished construction mitigation measures to increase the flood resilience of this critical infrastructure, including raising vulnerable infrastructure above flood levels (Figure 9).

This paper was presented at the WEF Collection Systems and Stormwater Conference, April 9-12, 2024.

SpeakerRudenko, Anastasia

Presentation time

14:00:00

14:30:00

Session time

13:30:00

16:45:00

SessionLocal Case Studies

Session number23

Session locationConnecticut Convention Center, Hartford, Connecticut

TopicClimate Change Adaptation, Collection Systems, Combined Sewer Overflow, Combined Sewer System, Construction, Deep Sewer Tunnel, Design Storm, Infiltration/Inflow, Precipitation Frequency, Sewer Separation, SSO Reduction, Stormwater Case Study/Application, Surface Water, Utility Management, Water Quality

Author(s)

Rudenko, Anastasia

Author(s)A. Rudenko1, M. Drainville1

Author affiliation(s)GHD 1

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Apr 2024

DOI10.2175/193864718825159378

Volume / Issue

Content sourceCollection Systems and Stormwater Conference

Word count14

Description: Adapting Wastewater Collection System Infrastructure to Changing Flood...

Adapting Wastewater Collection System Infrastructure to Changing Flood Vulnerabilities: Southeastern Massachusetts Case Studies

Abstract

SpeakerDrainville, Marc

Presentation time

08:30:00

08:50:00

Session time

08:30:00

10:30:00

SessionResilience for the Future: Designing Water and Wastewater Infrastructure for Resilience Against Intensifying Extreme Weather Events

Session number329

TopicPolicy and Regulation, Sustainability and Climate Change, Urban Systems

Author(s)

M. DrainvilleA. Rudenko

Author(s)M. Drainville1; A. Rudenko1;

Author affiliation(s)GHD, Inc.1

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2020

DOI10.2175/193864718825157870

Volume / Issue

Content sourceWEFTEC

Word count14

Boxed In: Wastewater Effluent Discharge Challenges in a Coastal Environment

Abstract

The coastline of southeastern Massachusetts is comprised of multiple estuarine systems. Nutrient enrichment, primarily associated with population growth and watershed land use changes, has exceeded these watersheds’ nitrogen assimilative capacities resulting in severe water quality degradation. Eutrophication is affecting environmental health, property values, and recreational opportunities. As communities evaluate options for nitrogen Total Maximum Daily Load (TMDL) compliance, they must also navigate issues related to returning treated effluent nitrogen load to impaired watersheds, groundwater mounding impacts on surface water systems, phosphorus load impacts to freshwater systems, and contaminants of emerging concern issues to public water supplies.

The coastline of Massachusetts is comprised of multiple estuarine systems experiencing degrading water quality due to nutrient enrichment. As communities evaluate options for nitrogen Total Maximum Daily Load (TMDL) compliance, they must navigate issues related to returning treated effluent nitrogen load to impaired watersheds, groundwater mounding impacts on surface water systems, phosphorus impacts to freshwater systems, and contaminants of emerging concern issues to public water supplies.

SpeakerRudenko, Anastasia

Presentation time

14:10:00

14:30:00

Session time

13:30:00

15:00:00

SessionFrom Fish Passage Design to Ocean Discharges: Going Coastal

Session locationRoom S402a - Level 4

TopicIntermediate Level, Watershed Management, Water Quality, and Groundwater

Author(s)

Rudenko, Anastasia

Author(s)A. Rudenko 1; M. Drainville 1 ; A. Rudenko 1;

Author affiliation(s)GHD 1; GHD 1 ; GHD 1;

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2023

DOI10.2175/193864718825159221

Volume / Issue

Content sourceWEFTEC

Word count11

Description: Increasing the Resilience of Vulnerable Coastal Wastewater Infrastructure in...

Increasing the Resilience of Vulnerable Coastal Wastewater Infrastructure in Southeastern Massachusetts to the impacts of Sea Level Rise

Abstract

Introduction Recently the Federal Emergency Management Agency (FEMA) redefined Base floodplains (more commonly known as 100 year floodplains) in Southeastern Massachusetts. In many coastal communities wastewater infrastructure that was previously considered to be outside the extent of the Base Flood is now shown to be vulnerable to this event. In addition, projections for sea level rise are expected to exacerbate flood risk in future years. One particularly vulnerable area is the low-lying coastal Town of Wareham, Massachusetts. The Town is nestled around Buzzards Bay, which creates several throttling points where catastrophic waves are anticipated to develop from Atlantic Ocean storms. As shown in Table 1, the Town has experienced several near 1% Flood events in the past 100 years. The Town's wastewater infrastructure, which is typically at the lowest elevations, is especially vulnerable to the newly established Base Flood. Background With the significant changes that have been made of late to the FEMA flood elevations, the State of Massachusetts has encouraged its coastal communities to shore up their coastal infrastructure. Through the Massachusetts Office of Coastal Zone Management (CZM), the State has provided funding to communities for projects that support proactive efforts to reduce a vulnerability to coastal flooding with consideration to changing environmental conditions. One proactive effort would be the shoring up of vulnerable, existing coastal wastewater infrastructure. In order to investigate the status of this infrastructure, one first needs to consider what elevation is a safe one for this infrastructure or what is the Design Flood Elevation (DFE). The DFE consists of a number of factors including the base flood elevation, a required minimum freeboard, and other factors the local community deems relevant such as sea level rise. A unique aspect of this project is that CZM requires that communities consider sea level rise when they establish a DFE. Although there are a number of projections for sea level rise, building codes do not yet require this to be considered. CZM requested an allowance be provided to demonstrate consideration for sea level rise. Figure 1 shows one sea level rise projection. Methodology The Town of Wareham (Town) is a coastal community in Southeastern Massachusetts with a year round population of approximately 20,000. The Town operates a wastewater system that serves approximately sixty percent of the Town. The system consists of 92 km (57 miles) of gravity sewer and force mains, 43 pump stations, and a Water Pollution Control Facility (WPCF). The collection system has significant environmental and economic importance to the Town. It serves the most populated portion of the Town as well as the Town's large seasonal summer population and day-trippers. The majority of the Town's pump stations are in vulnerable areas with respect to the Base Flood (especially considering subsequent anticipated wave action). With anticipated sea level rise due to climate change, many of the town's pump stations are in a very precarious position. Twenty nine of the Town's 43 pump stations are located within the Special Flood Hazard Area as shown in Figure 2. Additionally, infrastructure and multiple pump stations outside of flood zones rely on these stations to convey wastewater to the wastewater treatment facility. Figure 3 shows the interdependence of the Towns pump stations and critical infrastructure served by the stations. The evaluation of the twenty nine vulnerable stations included the development of a DFE which considered the base flood elevation, freeboard per the ASCE 24-14 — Flood Resistant Design and Construction reference and an allowance for sea level rise. This elevation was then projected onto each of the pump stations to assess the station's vulnerability (see Figure 4). CZM also required that the Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model be considered (see Figure 5). Anticipated impact from the Base Flood ranges from minimal damage to inundation of the station rendering the station inoperable.. With so many pump stations in vulnerable positions, a prioritization methodology needed to be developed. A Risk and Vulnerability Assessment was conducted using the risk and consequence approach outlined in 'Risk Analysis and Management for Critical Asset Protection (RAMCAP) Standard for Risk and Resilience Management for Risk and Resilience Management of Water and Wastewater Systems Using the ASTM-ITI RAMCAP Plus Methodology, 1st Edition (ANSI/AWWA J100- 10(R13))', a document commonly referred to as 'J100'. This document provides a methodology for communities, such as the Town of Wareham, to identify vulnerabilities within their system (as related to coastal flooding and climate change) and the risk associated with these vulnerabilities. Although The Hazards United States (HAZUS) model developed by FEMA to estimate potential losses in disasters was considered for use, the model was not able to converge with the complex coastline in Wareham. As a result, a Benefit Cost Analysis was developed using the FEMA software program BCA 5.1. This software analyzes proposed project costs and benefits, and produces a benefit-cost ratio (BCR). This model considered many factors including the local environment, critical facilities served and interdependency of pump stations. RESULTS Annual flood risks calculated for each station using the BCA methodology are shown in Table 2. Flood risk is the summation of the costs borne by the Town and its citizens. Costs to the Town include replacement of damaged or destroyed equipment and loss of essential services while the station is inoperable (such as hospital, police station, or fire department services). Costs to citizens include impact to natural resources, relocation costs during the period that their house has no sewer service and volunteer costs for clean-up efforts. Infrastructure with a higher annual flood risk typically serves many users, may serve critical infrastructure, and may have many pump stations that rely upon its proper functioning. Infrastructure with a lower annual flood risk typically serves less critical infrastructure and may have no pump stations that rely upon its operation. Conducting a 'Risk and Vulnerability Assessment' allowed the Town to prioritize which of its many competing coastal resilience wastewater infrastructure issues to address first. The Town has now initiated design work on three of its most vulnerable stations (Figure 6) which all serve critical infrastructure (a hospital, police station and fire department). Coastal resilience improvements to the pump stations include: relocating penetrations, installation of structural steel to shore up walls (Figure 7), and the use of carbon fiber to enhance reinforced masonry, raising elevations of generators, reinforcing or replacing walls and relocating portions of the infrastructure. The Town now has a plan and has begun to implement the plan that shall serve as a road map to shore up its most vulnerable wastewater infrastructure to make it more resilient to the impacts of tidal and sea level rise.

This paper was presented at the WEF Collection Systems and Stormwater Conference, April 9-12, 2024.

SpeakerDrainville, Marc

Presentation time

15:45:00

16:15:00

Session time

15:45:00

16:45:00

SessionTidal and Sea Level Rise Impact

Session number11

Session locationConnecticut Convention Center, Hartford, Connecticut

TopicClimate Change Adaptation, Design Storm, Lift Station, Modeling, Resiliency, Sea Level Rise, Stormwater Case Study/Application, Stormwater Management Design And Analysis, Tsunami, Wet Weather

Author(s)

Drainville, Marc

Author(s)M. Drainville1, A. Rudenko1

Author affiliation(s)GHD, Inc. 1

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Apr 2024

DOI10.2175/193864718825159346

Volume / Issue

Content sourceCollection Systems and Stormwater Conference

Word count19

Description: Integrated Approaches to Nutrient Management Planning: Southeastern Massachusetts...

Integrated Approaches to Nutrient Management Planning: Southeastern Massachusetts Case Studies

Abstract

Background The United States Environmental Protection Agency (USEPA) and Massachusetts Department of Environmental Protection (MassDEP) have implemented non-point-source, watershed-based nitrogen Total Maximum Daily Load (TMDL) limits for multiple small coastal estuaries in southeastern Massachusetts. Southeastern Massachusetts towns have approached this nitrogen contamination problem — primarily caused by overuse of septic systems as populations grew - in very different ways. Methodology Although almost all communities in the Study Area have explored growth neutral land use controls and solutions such as stormwater management and fertilizer reduction, some towns have taken a primarily traditional approach to solving the problem while others have explored alternative technologies. Some towns place an emphasis on traditional solutions such as sewering with an enhanced nitrogen removal process centralized wastewater treatment facility. Others have explored innovative non-traditional technologies such as shellfish aquaculture, permeable reactive barriers, inlet widening to improve tidal flushing, decentralized treatment facilities, and nitrogen reducing onsite septic systems. Many communities are developing a hybrid approach where traditional sewering is targeted for the highest density neighborhoods with non-traditional strategies being implemented in more less densely developed areas. Results Communities with TMDLs have initiated comprehensive wastewater management plans (CWMP) to develop methodologies to reduce nitrogen impacts. Representative case studies illustrate the unique solutions adopted by two of these communities; these both provide lessons learned to any community facing similar challenges. The communities of Oak Bluffs, MA and Chatham, MA each approached the CWMP process differently. Although the solutions were different, both communities faced a significant challenge- as a result of significant long term project costs — which has resulted in a robust public education effort. Case Study #1: Chatham's Septic to Sewer Strategy The Town of Chatham, MA has a severe nitrogen contamination problem. As shown in Figure 1, one third of the watersheds within the Town require 100% removal of wastewater nitrogen and almost three quarters require more than 50% removal of wastewater nitrogen to meet the Town's TMDL goals. The solution to this problem was estimated to cost over $300 million for a community with a year round population of just over 6000. In order to solve this problem, the Town developed a phased implementation approach. This approach primarily consists of planned implementation of traditional sewering technologies with limited non-traditional technologies for targeted areas. In the first phase of the plan the Town's existing Water Pollution Control Facility was upgraded to a limit of technology nitrogen removal process and its flow capacity was increased (Figure 3). The Town has been implementing septic to sewer conversion projects that account for approximately 15-20% of its TMDL compliance requirements every three years (Figure 2). Now almost 40% complete with its TMDL compliance plan, over 700 properties have been removed to date from septic systems, providing a potential future nitrogen load reduction of about 3,000 kg/y for this initial part of a larger long-term implementation program. In addition, the Town has completed an inlet widening project (Figure 4) as well as implemented a fertilizer management plan, the only two non-traditional nitrogen reduction options that were feasible to help address the significant contamination issues in this town. Overall, the Town plans to achieve its nitrogen TMDL goals within a 20-year timeframe. Case Study #2: Oak Bluffs Hybrid Nitrogen Management Approach The Town of Oak Bluffs is a small community with a year-round population of less than 5,000 people. The majority of the Town lies within one of four nitrogen sensitive coastal watersheds (Figure 5). Every summer, the Town sees a substantial population increase from tourism, which has contributed to the nutrient impacts observed in the Town's water resources. The Town has a small centralized wastewater treatment system, with limited options for treated effluent recharge expansion, which drove the Town to evaluate multiple non-traditional nitrogen management technologies as part of its comprehensive wastewater management plan (CWMP). In order to meet its nitrogen Total Maximum Daily Load limit goals, the Town has developed a hybrid Recommended Plan, which integrates multiple nitrogen management strategies for each watershed including centralized sewering, an enhanced nitrogen removal on-site septic system program, and permeable reactive barriers. The Recommended Plan includes the implementation of an adaptive management process to incorporate cost-effective pilot technologies into the plan once they demonstrate feasibility. The adaptive management process will involve ongoing water quality monitoring to monitor and respond to the results of the implementation. This adaptive management approach will enable the Recommended Plan to be adjusted based on the monitoring results of the environmental and economic impacts associated with the construction of sewers and implementation of pilot projects in Oak Bluffs. Benefits and Next Steps The complex wastewater nitrogen contamination challenges in southeastern Massachusetts require significant investments to reverse years of environmental degradation. This problem is being addressed by the small communities in Southeastern Massachusetts with innovative solutions that seek to manage high costs by balancing traditional and non-traditional wastewater management solutions. The solutions outlined above are allowing for the recovery of degraded coastal waterways using fiscal sustainable approaches. However, as the problem took many years to develop, so will the solutions with many of these comprehensive wastewater management plans having a schedule of 20, 30 and even 40 years to implement, making the results more of a long term goal.

This paper was presented at the WEF Collection Systems and Stormwater Conference, April 9-12, 2024.

SpeakerRudenko, Anastasia

Presentation time

15:45:00

16:15:00

Session time

15:45:00

16:45:00

SessionIntegrated Planning

Session number09

Session locationConnecticut Convention Center, Hartford, Connecticut

TopicFlooding, Hydrology & Hydraulics, Machine Learning, Septic to Sewer, TMDLs, Water Quality, Watershed Management

Author(s)

Rudenko, Anastasia

Author(s)A. Rudenko1, M. Drainville1

Author affiliation(s)GHD, 1

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Apr 2024

DOI10.2175/193864718825159387

Volume / Issue

Content sourceCollection Systems and Stormwater Conference

Word count11

Description: Solving a Massive Regional Wastewater Problem: Hybrid solutions employed by small...

Solving a Massive Regional Wastewater Problem: Hybrid solutions employed by small communities for affordable wastewater management in an effort to remediate widespread nutrient contamination

Abstract

Background
The United States Environmental Protection Agency (USEPA) and Massachusetts Department of Environmental Protection (MassDEP) have recently implemented non-point-source, watershed-based nitrogen Total Maximum Daily Load (TMDL) limits for multiple small coastal estuaries in southeastern Massachusetts. Cape Cod towns have addressed the nitrogen contamination problem â€“ primarily caused by overuse of septic systems as populations grew - in very different ways. These mostly small towns are fiercely independent, often dealing with residents resistant to community-wide sewer systems that some fear might lead to un-controlled growth. Overall the problem has been estimated to cost $4-8 billion dollars to solve, a cost that many fear is unaffordable.
Methodology Although almost all of the towns have explored growth neutral land use controls and solutions such as stormwater management and fertilizer reduction, some towns have taken a primarily traditional approach to solving the problem while others have explored alternative technologies. For example, some towns place an emphasis on traditional solutions such as sewering with a centralized wastewater treatment facility. Others have explored innovative non-traditional technologies such as shellfish aquaculture, permeable reactive barriers, inlet widening to improve tidal flushing, decentrailized treatment facilities, and innovative onsite septic systems. Of late, many communities are favoring a hybrid approach where traditional sewering is reserved for only the most highly contaminated areas densely populated areas while non-traditional approaches are explored wherever practical.
Results
Several of the Cape communities have initiated comprehensive wastewater management plans (CWMP) to develop methodologies to reduce nitrogen impacts. Representative case studies illustrate the unique solutions adopted by two of these communities; these both provide lessons learned to any community facing similar challenges. The communities of Falmouth, MA and Chatham, MA each approached the CWMP process differently and independently. Although the solutions were different, both communities faced a significant backlash - as a result of significant long term project costs - that has to be handled through a very carefully planned public education effort.
Case Study #1 - The Town of Chatham, MA has a severe nitrogen contamination problem. As shown in Figure 1, one third of the watersheds in town require 100% removal of wastewater nitrogen and almost three quarters require more than 50% removal of wastewater nitrogen. The solution to this problem was estimated to cost over $300 million for a community with a year round population of just over 6000. In order to solve this problem, the Town developed a phased implementation approach. This approach primarily consisted of planned implementation of traditional sewering technologies with limited non-traditional technologies for targeted areas. The Town has then implementing projects that account for approximately 15-20% of its TMDL compliance requirements every three years. Now almost 40% complete with its TMDL compliance plan, over 700 properties have been removed to date from septic systems, providing a potential future nitrogen load reduction of about 3,000 kg/y for this initial part of a larger long-term implementation program. In addition, the Town has completed an inlet widening project as well as implemented a fertilizer management plan, the only two non-traditional nitrogen reduction options that were feasible to help address the significant contamination issues in this town. Overall, the Town plans to have its TMDL compliance plan in place within a 20 year timeframe which is slated to be approximately by Year 2030.
Case Study #2 â€“ The Town of Falmouth has a similarly severe nitrogen contamination problem. As shown in Figure 2, one third of the watersheds require 100% removal of wastewater nitrogen and more than three quarters require more than 50% of the wastewater nitrogen to be removed. Traditional solutions to this wastewater nitrogen contamination including sewering and enhanced onsite septic systems were estimated to cost over a half billion dollars to implement. This cost made the project a nonstarter for the community of fewer than 40,000 people. A revised wastewater management plan was developed for Falmouth that included several key factors: 1) the Town would address its needs one watershed at a time and over a thirty year timeframe replacing debt drop off with new wastewater management spending to help control costs and 2) the overall solution included a balance between traditional and non-traditional solutions.
The implementation phase of the project began with the development of a Targeted Watershed Management Plan (TWMP) for one of the watersheds and the initiation of several pilot projects in other areas. The TWMP, which was the first approved TWMP in the state, was developed for a coastal estuary known as the Little Pond Watershed; this TWMP outlined the TMDL compliance strategy for 100 percent removal of controllable nitrogen levels in this watershed. The primary mechanism of compliance was achieved by installing a centralized wastewater collection system in a densely populated, built-out portion of Town, doubling the existing collection system size and capacity. This project is estimated to reduce the concentration of nitrogen in the impacted estuary from 0.837 mg/L to 0.495 mg/L, nearly 90% of the TMDL goal for this watershed. Other strategies to help the Town achieve the balance of the TMDL included: continued use of on-site treatment and disposal; fertilizer management; stormwater management; shellfish aquaculture; and widening the inlet opening to the coastal pond. Demonstration projects for alternative solutions including shellfish aquaculture, composting toilets and permeable reactive barriers yielded unfavorable results for composting toilets with shellfish and permeable reactive barriers still being considered.
With the Little Pond watershed TMDL compliance plan nearly complete, the Town has now initiated its planning for the second watershed â€“ Great Pond. This project planning is expected to be complete in 2022 with implementation expected to begin in that same year. The Town is on its way to achieve TMDL compliance by Year 2045.
Benefits and Concerns
The complex wastewater nitrogen contamination challenges in southeastern Massachusetts have created a $4-8 billion issue. A problem that developed over many decades as growth exploded is being met by the small communities on Cape Cod with innovative solutions that seek to manage high costs by balancing traditional and non-traditional wastewater management solutions. The solutions outlined above are allowing for the recovery of a seriously degraded water environment in an affordable manner. However, as the problem took many years to develop, so will the solutions with many of these comprehensive wastewater management plans having a schedule of 20, 30 and even 40 years to implement, making the results more of a long term goal.

Cape Cod Massachusetts towns have addressed a nitrogen contamination problem primarily caused by overuse of septic systems as populations grew - in very different ways. A problem that developed over many decades as growth exploded is being met by the small communities on Cape Cod with innovative solutions that seek to manage high costs by balancing traditional and non-traditional wastewater management solutions.

SpeakerDrainville, Marc

Presentation time

16:30:00

16:55:00

Session time

15:30:00

17:00:00

TopicFundamental Level, Small Communities and Decentralized Systems, Utility Management and Leadership

Author(s)

Drainville, Marc

Author(s)Marc R. Drainville1

Author affiliation(s)GHD Inc., Hyannis, MA1

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2022

DOI10.2175/193864718825158733

Volume / Issue

Content sourceWEFTEC

Word count25

Description: The Sewering of an Entire Town: How Chatham, Massachusetts is Planning to Gain...

The Sewering of an Entire Town: How Chatham, Massachusetts is Planning to Gain Complete Control of Their Wastewater in order to Protect the Coastal Environment

Abstract

BACKGROUND The United States Environmental Protection Agency (USEPA) and Massachusetts Department of Environmental Protection (MassDEP) have recently implemented non-point-source, watershed-based nitrogen Total Maximum Daily Load (TMDL) limits for multiple small coastal estuaries around Cape Cod Massachusetts. The TMDLs for the four (4) estuarine systems around the Town of Chatham, Massachusetts, a town with a population of approximately 6500, are very stringent and require removal of much of the wastewater nitrogen coming from the many individual septic systems, as well as nitrogen from the stormwater and lawn fertilizers, at the many developed properties (see Figure 1). Nutrients have been overloading the local estuaries for years causing highly visible eutrophication issues as well as impacts to the groundwater-source drinking water supply. Based on these nitrogen TMDLs, the Town developed a Comprehensive Wastewater Management Plan (CWMP) which utilizes sewer extensions, a wastewater treatment facility upgrade, growth neutral land use controls, stormwater management, and fertilizer reduction research and management to meet the limits. THE PROBLEM AND ITS SOLUTION The Town has historically relied almost exclusively on individual septic systems for wastewater management. Once nitrogen was determined to be the nutrient of concern with respect to the local estuaries, sources of nitrogen were investigated. Almost 70% of the total nitrogen was identified as coming from wastewater and a full 85% of nitrogen from all controllable sources (fertilizers, stormwater, wastewater/septic system) was wastewater related (see Figures 1 and 2). Although many treatment systems were investigated including traditional and enhanced septic systems, cluster and decentralized systems and large-scale municipal wastewater facilities, it was the centralized treatment facility with its 93% removal of nitrogen that was needed to meet the strict TMDLs which required overall effluent levels to be at the limit of technology for nitrogen. In order to remove nitrogen to the extent shown in Figure 3, the Town has begun an extensive sewering project which will sewer two thirds of the Town in Phase 1 (which is expected to be complete within twenty years) and the balance of the town would be sewered in an additional ten years during Phase 2 as shown in Figure 4. In order to accommodate this additional wastewater, the water pollution control facility was upgraded significantly including nitrogen removal to 3 mg/L and accommodations for future phosphorus removal. The total cost of the extensive sewering and treatment upgrade project is projected to be approximately $300 million dollars with more than two thirds of those costs ($210 million) being for the Phase 1. THE APPROACH The Town-wide approval of the plan was the result of a focus on outreach and public participation. This consisted of the creation of a citizens advisory committee (CAC) which contributed to the development of the CWMP. A key component of the plan that maintained the public's support was a 'Growth Neutral' bylaw which allowed for controlled 'wastewater related' growth within the Town. The involvement of the public through the CAC, public meetings, and other means was a primary reason why this CWMP gained approval where other town plans failed. In addition, the cost of the Plan was made affordable by spreading costs to all property owners, and by capturing scarce federal grants and taking full advantage of state and federal loan programs. IMPLEMENTATION As part of the Planning stage, an extensive Sewer CADD model of the entire Town was developed (results shown in Figure 4). This model included Phase 1 and Phase 2 of the CWMP implementation. The flat terrain in this coastal community resulted in the projection of over eighty pumping stations being needed for this small Town with a year-round population of only 6500. This model provided the roadmap needed to commence the Town-wide sewering project. In 2009, the initial implementation phase of this plan commenced with the 'backbone' of the collection system being designed and constructed. This 'backbone' consisted of the main gravity sewer lines and forcemains installed across the Town that will serve the vast majority of the expanded system. With both the backbone of the system and the wastewater treatment facility upgrade completed in 2012, a series of smaller collection system offshoots will commence in the ensuing years with the Town committing to a continuous sequence of small sewer extensions over the next few decades. As shown in Figure 5, the newly upgraded wastewater treatment facility has been removing nitrogen to the limit of technology since the initial startup was complete in the summer of 2012. SOCIAL, ECOMONIC, AND SUSTAINABLE DESIGN COMPONENTS This Project provided a roadmap for the Town to follow to solve problems created mostly by wastewater and provides the following social and economic benefits in Chatham: -A planning document outlining a wastewater solution -Remediation and protection of drinking, pond, and estuarine water quality -Preservation of the Town's fishing economy -Preservation of the Town's vacation economy -Land use growth protection (Flow Neutral) to apply to all properties connected to the sewer -Costs being distributed in an affordable manner. The historic use of septic systems as the primary type of wastewater management in Chatham was not sustainable because it was causing eutrophication of its coastal estuaries and freshwater ponds, and threatening its groundwater drinking water supplies. The CWMP recommendations of wastewater collection, advanced treatment, and treated-water recharge to the groundwater system provided a sustainable and holistic method for water resource management. Through the Town's efforts in completing their CWMP and growth neutral policy, they were also able to secure 0% SRF loans for this and their next phase of sewer extensions, over the 2% loans normally available. CURRENT STATUS The CWMP outlines a phased implementation of the Phase I sewering. With the initial implementation phase complete, the planning documents and SewerCADD models are now in use as the expansion of the collection system continues with annual sewering projects. The long-term plan to remediate the impaired waters is well underway as the Town has implemented its plan to gain complete control of their wastewater.

This paper was presented at the WEF Collection Systems and Stormwater Conference, April 9-12, 2024.

SpeakerDrainville, Marc

Presentation time

15:45:00

16:45:00

Session time

15:45:00

16:45:00

SessionIntegrated Planning

Session number09

Session locationConnecticut Convention Center, Hartford, Connecticut

TopicFlooding, Hydrology & Hydraulics, Machine Learning, Septic to Sewer, TMDLs, Water Quality, Watershed Management