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The project will retrofit an existing stormwater detention basin with a series of green stormwater infrastructure improvements designed to slow, capture, and naturally treat stormwater runoff. The basin project, located between King Road and Mount Arlington Boulevard in Roxbury Township, was identified in the 2021 Upper Musconetcong River Implementation Plan (WIP) as a priority project to reduce non-point source pollution and improve water quality before stormwater enters the lake at King Cove. "Roxbury is truly thankful for the Lake Hopatcong Commission. Lake Hopatcong is such a valuable resource and the commission’s work alongside Princeton Hydro has preserved a natural treasure," said Shawn Potillo, Mayor of Roxbury. "We are grateful to the NJDEP for their support and award of this grant. This water basin project in Roxbury will help continue the commission’s purpose of keeping the lake a beautiful place to swim, boat, relax, and call home." A range of improvements will be incorporated including planting native vegetation and managing invasive species to stabilize soils, support wildlife, and naturally filter pollutants before they reach the lake. Erosion and sediment control measures will further protect the area by reducing stormwater scouring and preventing bank degradation. In addition to on-the-ground restoration, the project emphasizes public education and outreach to promote best management practices and ongoing watershed stewardship among residents and local partners. Project success will be evaluated through water quality monitoring conducted before and after construction, providing measurable data on the project’s effectiveness in improving water quality. “Lake Hopatcong’s fight against harmful algal blooms requires a united front, where many projects, like retrofitting stormwater basins to capture nutrients before they go into the lake, collectively make a big impact,” said Dr. Fred Lubnow, Senior Technical Director of Ecological Services at Princeton Hydro. “Thanks to the leadership of the Lake Hopatcong Commission and the Lake Hopatcong Foundation, this collaborative approach is driving real progress toward cleaner water, healthier ecosystems, and a more resilient future for New Jersey’s largest lake.” The basin enhancement project is funded through NJDEP’s Water Quality Restoration Grant Program, which is supported by the U.S. Environmental Protection Agency under Clean Water Act Section 319(h). Along with the state grant, the project includes a $200,000 local match from the Commission, Roxbury Township, and the Lake Hopatcong Foundation, and builds on a $98,000 planning grant awarded by the New Jersey Highlands Council in 2024 that helped prepare the project for implementation and future grant opportunities. “This project represents an important step forward in improving Lake Hopatcong’s water quality and reducing pollutants that contribute to harmful algal blooms,” said Ron Smith, Chairman of the Lake Hopatcong Commission. “We’re grateful to NJDEP, Roxbury Township, Princeton Hydro, the Foundation and the Highlands Council for their continued partnership in protecting this vital resource.” [caption id="attachment_18637" align="aligncenter" width="1380"] Photo by the Lake Hopatcong Commission[/caption] The Lake Hopatcong Commission is an independent state agency created in, but not of, the New Jersey Department of Environmental Protection. LHC is recognized as a steward of the lake and watershed. The 11-member Board of State and local appointees include representatives of the four municipalities and two counties surrounding Lake Hopatcong. LHC is responsible for fulfilling the obligations of the Lake Hopatcong Protection Act, to safeguard Lake Hopatcong as a natural, scenic, and recreational resource. To learn more, click here to visit lakehopatcongcommission.org. For over 30 years, Princeton Hydro has been proud to work alongside the Lake Hopatcong Commission and Lake Hopatcong Foundation in support of the lake’s health and resilience. Through these partnerships, and with the support of numerous funding agencies, a wide range of projects have been implemented to reduce pollutant loads, manage stormwater runoff, address invasive species and harmful algal blooms, and enhance habitat quality—helping to protect both the lake and the communities that depend on it. To learn more about our collaborative efforts, click here. [post_title] => Lake Hopatcong Commission Awarded $367,000 NJDEP Grant for Water Quality Improvements in Roxbury Township [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => lake-hopatcong-commission-awarded-367000-njdep-grant-for-water-quality-improvements-in-roxbury-township [to_ping] => [pinged] => [post_modified] => 2025-11-10 17:09:04 [post_modified_gmt] => 2025-11-10 17:09:04 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=18636 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 18586 [post_author] => 1 [post_date] => 2025-11-06 00:15:54 [post_date_gmt] => 2025-11-06 00:15:54 [post_content] => The New Jersey Department of Environmental Protection (NJDEP) recently announced $8 million in Water Quality Restoration Grants to support projects that reduce nonpoint source pollution, mitigate harmful algal blooms, restore riparian areas, and enhance watershed and climate resilience. Funded through Section 319(h) of the federal Clean Water Act and administered by the DEP's Watershed and Land Management Program, these grants were awarded to municipalities, nonprofit organizations, and academic institutions across the state. Princeton Hydro is proud to be a partner on five of the 17 funded projects. Our contributions vary by project and encompass activities such as engineering design, water quality assessment, watershed-based planning, and technical support for implementing stormwater and habitat restoration measures. Let's take a deeper look at these collaborative efforts: 1. The Watershed Institute – Watershed-Based Planning for Assunpink Creek The Watershed Institute received $205K in 319(h) grant funding to develop a watershed-based plan for the Assunpink Creek watershed, located within the Raritan River Basin. This watershed spans 11 municipalities across two counties, where varied landscapes and demographics share common challenges such as localized flooding, stormwater management, and water quality degradation, highlighting the need for a coordinated, watershed-wide, science-driven approach. The plan will evaluate pollution sources and identify large-scale restoration opportunities, including green infrastructure and riparian buffer restoration, to improve water quality and reduce flooding. It will also assess the cost, feasibility, and pollutant reduction potential of proposed measures to ensure practical implementation. Princeton Hydro supported the Institute in developing the grant proposal and planning framework, leveraging our expertise in watershed-based planning to prioritize nature-based solutions that address both water quality and climate resilience. This initiative represents a critical step toward regional collaboration, enabling upstream and downstream communities to work together on strategies that strengthen watershed health, protect public safety, and build long-term resilience. 2. Lake Hopatcong Commission – Watershed-Based Stormwater BMPs The Lake Hopatcong Commission (LHC) was awarded $366K to retrofit an existing stormwater detention basin between King Road and Mount Arlington Boulevard in Roxbury Township. This retrofit is part of a larger Watershed Implementation Plan that Princeton Hydro developed in collaboration with LHC, which prioritizes nutrient reduction and stormwater management strategies across the Lake Hopatcong watershed. Over the past several years, LHC has actively implemented multiple elements of this plan to address harmful algal blooms (HABs) and improve water quality. For this project, Princeton Hydro is providing engineering design and technical oversight to transform the existing basin into a green stormwater infrastructure system that slows, captures, and naturally treats runoff before it enters King Cove. The design incorporates native vegetation, invasive species management, and erosion control measures to stabilize soils and filter pollutants, reducing nutrient loading, which is one key driver of HABs. Public outreach and pre- and post-construction water quality monitoring will ensure performance tracking and measurable improvements. This basin retrofit represents a critical step in a coordinated, science-based approach to restoring ecological health and water quality in New Jersey’s largest lake. 3. Cozy Lake, Jefferson Township – Addressing Emerging Contaminants Jefferson Township received $350K in grant funding to develop an Emerging Contaminants Management Plan for Cozy Lake, focusing on cyanotoxins and HABs. Cozy Lake is a 28-acre waterbody within a 1,152-acre sub-watershed that includes both forested (60%) and developed (29%) land. The lake is fed by the Rockaway River at its northern end and a smaller southeastern inlet, with outflow through a dam on the western edge. The shoreline is primarily residential lawn with minimal emergent wetlands, and several inlets and rock-lined drainage ditches exhibit erosion and lack slope protection, contributing to sediment loading. Princeton Hydro provided early technical input to shape this innovative project with the creation of a comprehensive Jefferson Township Lake and Watershed Restoration and Protection Plan. As part of the plan, Princeton Hydro made recommendations for Cozy Lake, which included enhancing shoreline buffers with native vegetation and installing living shorelines at select properties to stabilize soils, filter stormwater and reduce nutrient loading, improve habitat quality, and enhance community access. These measures, combined with in-lake monitoring and proactive management strategies, will help mitigate HABs and protect ecological and public health. 4. Rockaway Township – Watershed-Based Green Infrastructure Rockaway Township received $399K in grant funding to implement elements of its Watershed Implementation Plan, focusing on green infrastructure stormwater management and nutrient reduction to improve water quality. The project will retrofit the municipal complex by converting a rock-lined drainage swale into a vegetated swale with a bioretention basin, designed to filter stormwater runoff and reduce nonpoint source pollutants entering Fox’s Pond and Fox Brook. Princeton Hydro played a key role in developing the Watershed Implementation Plan, which encompasses 11 private lakes within the Rockaway River watershed, prioritizing critical locations for intervention and designing cost-effective green infrastructure BMPs. This regional approach aligns with strategies recommended by NJDEP and the Highlands Council. The plan included a comprehensive watershed-based assessment to identify and quantify factors contributing to eutrophication, evaluate management measures, estimate costs, and establish an implementation schedule. Princeton Hydro authored the final report, which guided the Township in applying for the Section 319(h) grant and now informs the design and construction of green stormwater infrastructure that will deliver measurable water quality improvements while supporting ecological restoration goals. 5. Green Trust Alliance – Green Infrastructure and Community Engagement Green Trust Alliance (GTA), a nationally accredited land trust and public charity dedicated to accelerating large-scale conservation, received $1.39 million in NJDEP funding to implement green infrastructure improvements at Pinelands Regional High School in Tuckerton, New Jersey. This initiative targets the Tuckerton Creek watershed, which drains into Tuckerton Creek and ultimately flows into Barnegat Bay—a critical estuary spanning 33 municipalities in Ocean County and four in Monmouth County. The retrofit will transform the school’s stormwater detention basin into a multi-functional system that mimics natural hydrology, enhances flow control, and improves water quality locally and in the larger Barnegat Bay watershed. Working with GTA and GreenVest, Princeton Hydro is serving as the design engineer, applying nature-based engineering and ecological restoration techniques to intercept, evapotranspire, and infiltrate stormwater runoff at its source. In addition to its technical objectives, the effort includes a strong community engagement component and an educational platform for students. By bringing green infrastructure into the school environment, the initiative provides hands-on experience with water resources, stormwater management, and ecological engineering, help to build STEM skills while fostering a deeper connection to the surrounding landscape and an understanding of how natural systems work together to support environmental and community health. Princeton Hydro also assisted several of these partners in developing successful NJDEP Section 319(h) grant applications, providing technical documentation, conceptual designs, and pollutant load reduction estimates to strengthen the proposals. To date, the Murphy Administration has awarded more than $33M in Water Quality Restoration grants to improve the health of waterways in all corners of the state. Click here to read about all the 2025 grant funding recipients and their innovative projects. As NJDEP Environmental Protection Commissioner Shawn M. LaTourette noted in the department's press release, “Enhancing the ecological health of our lakes, rivers, streams and coastal waters has long been a priority of the Murphy Administration. The Department of Environmental Protection is pleased to award these grants that will help our partners advance a variety of strategies to improve the health of these waterways and enhance the quality of life in our communities.” We are proud to play a continued role in advancing that mission: helping communities implement practical, data-driven solutions that make a measurable difference for New Jersey’s waterways and the people who depend on them. Click here to learn more about our work to protect natural habitat and restore water quality throughout the New Jersey. [post_title] => NJDEP Awards $8M for Water Quality Restoration Projects [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => njdep-319h-grants-2025 [to_ping] => [pinged] => [post_modified] => 2025-11-07 01:20:58 [post_modified_gmt] => 2025-11-07 01:20:58 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=18586 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [2] => WP_Post Object ( [ID] => 15090 [post_author] => 1 [post_date] => 2024-06-11 18:25:13 [post_date_gmt] => 2024-06-11 18:25:13 [post_content] => By Dr. Fred Lubnow, Senior Technical Director of Ecological Services As we reflect on the winter of 2023-2024, it's evident that New Jersey experienced another unusually mild season, mirroring the winter of 2022-2023. Notably, Lake Hopatcong, located in Sussex and Morris Counties, remained virtually ice-free throughout the winter, with only a brief period of minor ice formation in early January. This pattern was not isolated to Lake Hopatcong; many lakes across the state and the broader Mid-Atlantic region exhibited similar ice-free conditions. Such conditions can lead to increased algal and plant growth earlier in the year. Adding to this, from January to early June 2024, 15 of New Jersey's 21 counties recorded precipitation levels 26% to 50% higher than their long-term averages. The remaining six counties, predominantly in the southern part of the state, had precipitation increases of 11% to 25% above their long-term normals. This heightened precipitation is significant as it can transport nutrients, most notably phosphorus and nitrogen, into water bodies, potentially fueling the growth of algae. Compounding these factors, long-range climate models and trends suggest that the summer of 2024 could rank among the hottest on record. The combination of a mild winter, increased precipitation, and anticipated high summer temperatures sets the stage for conditions similar to those experienced in 2019, a year marked by widespread harmful algal blooms (HABs) in numerous lakes. HABs, characterized by rapid overgrowths of cyanobacteria, present serious challenges to water quality and aquatic ecosystems. Cyanobacteria, or blue-green algae, naturally occur in aquatic environments but can proliferate rapidly under warm, nutrient-rich conditions. These blooms pose risks to human health, wildlife, aquatic species, local economies, and the overall ecological balance. The interplay between climate change and HABs is undeniable: rising temperatures and altered precipitation patterns foster conditions that exacerbate bloom occurrences. Given these circumstances, it is crucial for lake managers and water utilities to adopt proactive measures. Early and consistent sampling efforts can detect cyanobacteria and akinetes, dormant spores that contribute to bloom formation. Additionally, reducing nutrient inputs, particularly phosphorus, into waterways is essential to prevent HABs. Princeton Hydro strongly recommends that lake managers, water utilities, and concerned community members closely monitor their lakes, reservoirs, and riverways to stay as proactive as possible in managing these valuable resources. By raising awareness, fostering collaboration, and implementing effective strategies, we can work towards safeguarding the health and sustainability of our freshwater ecosystems. Together, we can address the challenges posed by HABs and protect the integrity of our water bodies. For more information about HABs, click here. Dr. Fred Lubnow, Princeton Hydro’s Senior Technical Director, Ecological Services, is an expert in aquatic and watershed management, restoration ecology, community and ecosystem ecology, and the use of benthic macroinvertebrate and fish in-stream bioassessment protocols. Dr. Lubnow has managed hundreds of lake projects and provides technical expertise for a variety of lake and watershed restoration projects. His experience in lake and reservoir restoration includes the design and implementation of dredging, aeration, chemical control of nuisance species, nutrient inactivation (i.e. alum) and biomanipulation. His experience in watershed restoration includes the design and implementation of structural Best Management Practices (BMPs), the development of Total Maximum Daily Load (TMDL) pollutant budgets, and the design, implementation and analysis of watershed-based monitoring programs. [post_title] => Preparing for Potential Harmful Algal Blooms: An Urgent Call to Action for NJ's Lakes and Reservoirs [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => an-urgent-call-to-action-habs [to_ping] => [pinged] => [post_modified] => 2024-06-11 18:25:13 [post_modified_gmt] => 2024-06-11 18:25:13 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=15090 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [3] => WP_Post Object ( [ID] => 13355 [post_author] => 1 [post_date] => 2023-08-16 07:03:24 [post_date_gmt] => 2023-08-16 07:03:24 [post_content] => 400 native plants were installed along the western shoreline of Memorial Pond in Mount Arlington, New Jersey. The planting was completed in one day by a team of 20+ volunteers, staff members from Mt. Arlington Department of Public Works (DPW), Lake Hopatcong Foundation, Lake Hopatcong Commission, Princeton Hydro, and a generous community member who volunteered his excavating equipment (and time). The planting initiative aims to prevent shoreline erosion, promote the growth of native species, increase wildlife habitat, and improve the water quality of Memorial Pond and Lake Hopatcong. Funding for this project was secured through a grant from the New Jersey Department of Environmental Protection, awarded to the Lake Hopatcong Commission in partnership with the Lake Hopatcong Foundation. [caption id="attachment_13422" align="aligncenter" width="616"] Photo by Lake Hopatcong Foundation Executive Director Kyle Richter[/caption] Memorial Pond Memorial Pond is a 0.3-acre stormwater runoff basin that gradually releases into Glen Brook, which then flows into Lake Hopatcong. The pond receives sheet flow of stormwater from the adjacent road, which contributes to nutrient and sediment loading, thus locally reducing water quality in Memorial Pond and ultimately the waters of Lake Hopatcong. Memorial Park, which includes Memorial Pond and Glen Brook, was identified by Princeton Hydro and the Lake Hopatcong team as a priority site for improvement, targeting initiatives that reduce pollutants and excessive nutrients entering into Lake Hopatcong. Additionally, the pond’s steeply-sloped shoreline was bare and only stabilized with large rocks at the base of the banks. In the absence of stabilizing vegetation, the pond’s banks were experiencing erosion, and there was some concern about a few mature trees along the shoreline potentially falling into the pond. [gallery link="none" ids="13416,13407,13413"] The photos above were taken in April 2023 before the planting initiative. Shoreline Planting Initiative The plant selection and layout were designed taking into account the steep slope and presence of mature, existing trees as well as focusing on regionally native plant species that will thrive and help stabilize the eroding shoreline. The planting team, led by Princeton Hydro Landscape Architect Jamie Feinstein, RLA and Aquatics Project Manager Pat Rose, was given precise instructions on how to install the plants to eliminate washouts and ensure the root systems can embrace the soil and hold it in place. A variety of native herbaceous plants and shrubs were chosen for the site, including pennsylvania sedge, slender mountain mint, blue flag iris, sweet azalea, smooth hydrangea, and maple-leaved viburnum. [gallery link="none" ids="13427,13421,13428"] The plants will help reduce stormwater flow, absorb excess nutrients, prevent erosion, and ultimately decrease sedimentation to the pond, while creating a visually pleasing addition to the park and providing a habitat for pollinators and birds. Overall, this project promotes a healthier and more balanced ecosystem in Memorial Park. [gallery link="none" ids="13400,13392,13394"] The photos above were taken in July 2023 immediately after the planting initiative. Multi-Faceted Approach to Water Quality Improvements The installation of these beneficial plants is part of a series of water quality initiatives on Lake Hopatcong funded by a NJDEP Freshwater Harmful Algal Bloom (HAB) Prevention & Management Grant and 319(h) Grant awarded to Lake Hopatcong Commission in partnership with the Lake Hopatcong Foundation. Additional initiatives included in the watershed implementation and HABs management plan are, the installation of:
The Lake Hopatcong Commission, in partnership with Roxbury Township and Princeton Hydro, and with support from the Lake Hopatcong Foundation, has been awarded a $367,000 Water Quality Restoration Grant from the New Jersey Department of Environmental Protection (NJDEP) for the Lake Hopatcong Watershed Basin Enhancement Project.
The project will retrofit an existing stormwater detention basin with a series of green stormwater infrastructure improvements designed to slow, capture, and naturally treat stormwater runoff. The basin project, located between King Road and Mount Arlington Boulevard in Roxbury Township, was identified in the 2021 Upper Musconetcong River Implementation Plan (WIP) as a priority project to reduce non-point source pollution and improve water quality before stormwater enters the lake at King Cove.
"Roxbury is truly thankful for the Lake Hopatcong Commission. Lake Hopatcong is such a valuable resource and the commission’s work alongside Princeton Hydro has preserved a natural treasure," said Shawn Potillo, Mayor of Roxbury. "We are grateful to the NJDEP for their support and award of this grant. This water basin project in Roxbury will help continue the commission’s purpose of keeping the lake a beautiful place to swim, boat, relax, and call home."
A range of improvements will be incorporated including planting native vegetation and managing invasive species to stabilize soils, support wildlife, and naturally filter pollutants before they reach the lake. Erosion and sediment control measures will further protect the area by reducing stormwater scouring and preventing bank degradation.
In addition to on-the-ground restoration, the project emphasizes public education and outreach to promote best management practices and ongoing watershed stewardship among residents and local partners. Project success will be evaluated through water quality monitoring conducted before and after construction, providing measurable data on the project’s effectiveness in improving water quality.
“Lake Hopatcong’s fight against harmful algal blooms requires a united front, where many projects, like retrofitting stormwater basins to capture nutrients before they go into the lake, collectively make a big impact,” said Dr. Fred Lubnow, Senior Technical Director of Ecological Services at Princeton Hydro. “Thanks to the leadership of the Lake Hopatcong Commission and the Lake Hopatcong Foundation, this collaborative approach is driving real progress toward cleaner water, healthier ecosystems, and a more resilient future for New Jersey’s largest lake.”
The basin enhancement project is funded through NJDEP’s Water Quality Restoration Grant Program, which is supported by the U.S. Environmental Protection Agency under Clean Water Act Section 319(h). Along with the state grant, the project includes a $200,000 local match from the Commission, Roxbury Township, and the Lake Hopatcong Foundation, and builds on a $98,000 planning grant awarded by the New Jersey Highlands Council in 2024 that helped prepare the project for implementation and future grant opportunities.
“This project represents an important step forward in improving Lake Hopatcong’s water quality and reducing pollutants that contribute to harmful algal blooms,” said Ron Smith, Chairman of the Lake Hopatcong Commission. “We’re grateful to NJDEP, Roxbury Township, Princeton Hydro, the Foundation and the Highlands Council for their continued partnership in protecting this vital resource.”
The Lake Hopatcong Commission is an independent state agency created in, but not of, the New Jersey Department of Environmental Protection. LHC is recognized as a steward of the lake and watershed. The 11-member Board of State and local appointees include representatives of the four municipalities and two counties surrounding Lake Hopatcong. LHC is responsible for fulfilling the obligations of the Lake Hopatcong Protection Act, to safeguard Lake Hopatcong as a natural, scenic, and recreational resource. To learn more, click here to visit lakehopatcongcommission.org.
For over 30 years, Princeton Hydro has been proud to work alongside the Lake Hopatcong Commission and Lake Hopatcong Foundation in support of the lake’s health and resilience. Through these partnerships, and with the support of numerous funding agencies, a wide range of projects have been implemented to reduce pollutant loads, manage stormwater runoff, address invasive species and harmful algal blooms, and enhance habitat quality—helping to protect both the lake and the communities that depend on it. To learn more about our collaborative efforts, click here.
The New Jersey Department of Environmental Protection (NJDEP) recently announced $8 million in Water Quality Restoration Grants to support projects that reduce nonpoint source pollution, mitigate harmful algal blooms, restore riparian areas, and enhance watershed and climate resilience. Funded through Section 319(h) of the federal Clean Water Act and administered by the DEP's Watershed and Land Management Program, these grants were awarded to municipalities, nonprofit organizations, and academic institutions across the state.
Princeton Hydro is proud to be a partner on five of the 17 funded projects. Our contributions vary by project and encompass activities such as engineering design, water quality assessment, watershed-based planning, and technical support for implementing stormwater and habitat restoration measures. Let's take a deeper look at these collaborative efforts:
The Watershed Institute received $205K in 319(h) grant funding to develop a watershed-based plan for the Assunpink Creek watershed, located within the Raritan River Basin. This watershed spans 11 municipalities across two counties, where varied landscapes and demographics share common challenges such as localized flooding, stormwater management, and water quality degradation, highlighting the need for a coordinated, watershed-wide, science-driven approach.
The plan will evaluate pollution sources and identify large-scale restoration opportunities, including green infrastructure and riparian buffer restoration, to improve water quality and reduce flooding. It will also assess the cost, feasibility, and pollutant reduction potential of proposed measures to ensure practical implementation. Princeton Hydro supported the Institute in developing the grant proposal and planning framework, leveraging our expertise in watershed-based planning to prioritize nature-based solutions that address both water quality and climate resilience. This initiative represents a critical step toward regional collaboration, enabling upstream and downstream communities to work together on strategies that strengthen watershed health, protect public safety, and build long-term resilience.
The Lake Hopatcong Commission (LHC) was awarded $366K to retrofit an existing stormwater detention basin between King Road and Mount Arlington Boulevard in Roxbury Township. This retrofit is part of a larger Watershed Implementation Plan that Princeton Hydro developed in collaboration with LHC, which prioritizes nutrient reduction and stormwater management strategies across the Lake Hopatcong watershed. Over the past several years, LHC has actively implemented multiple elements of this plan to address harmful algal blooms (HABs) and improve water quality.
For this project, Princeton Hydro is providing engineering design and technical oversight to transform the existing basin into a green stormwater infrastructure system that slows, captures, and naturally treats runoff before it enters King Cove. The design incorporates native vegetation, invasive species management, and erosion control measures to stabilize soils and filter pollutants, reducing nutrient loading, which is one key driver of HABs. Public outreach and pre- and post-construction water quality monitoring will ensure performance tracking and measurable improvements. This basin retrofit represents a critical step in a coordinated, science-based approach to restoring ecological health and water quality in New Jersey’s largest lake.
Jefferson Township received $350K in grant funding to develop an Emerging Contaminants Management Plan for Cozy Lake, focusing on cyanotoxins and HABs. Cozy Lake is a 28-acre waterbody within a 1,152-acre sub-watershed that includes both forested (60%) and developed (29%) land. The lake is fed by the Rockaway River at its northern end and a smaller southeastern inlet, with outflow through a dam on the western edge.
The shoreline is primarily residential lawn with minimal emergent wetlands, and several inlets and rock-lined drainage ditches exhibit erosion and lack slope protection, contributing to sediment loading. Princeton Hydro provided early technical input to shape this innovative project with the creation of a comprehensive Jefferson Township Lake and Watershed Restoration and Protection Plan. As part of the plan, Princeton Hydro made recommendations for Cozy Lake, which included enhancing shoreline buffers with native vegetation and installing living shorelines at select properties to stabilize soils, filter stormwater and reduce nutrient loading, improve habitat quality, and enhance community access. These measures, combined with in-lake monitoring and proactive management strategies, will help mitigate HABs and protect ecological and public health.
Rockaway Township received $399K in grant funding to implement elements of its Watershed Implementation Plan, focusing on green infrastructure stormwater management and nutrient reduction to improve water quality. The project will retrofit the municipal complex by converting a rock-lined drainage swale into a vegetated swale with a bioretention basin, designed to filter stormwater runoff and reduce nonpoint source pollutants entering Fox’s Pond and Fox Brook.
Princeton Hydro played a key role in developing the Watershed Implementation Plan, which encompasses 11 private lakes within the Rockaway River watershed, prioritizing critical locations for intervention and designing cost-effective green infrastructure BMPs. This regional approach aligns with strategies recommended by NJDEP and the Highlands Council. The plan included a comprehensive watershed-based assessment to identify and quantify factors contributing to eutrophication, evaluate management measures, estimate costs, and establish an implementation schedule. Princeton Hydro authored the final report, which guided the Township in applying for the Section 319(h) grant and now informs the design and construction of green stormwater infrastructure that will deliver measurable water quality improvements while supporting ecological restoration goals.
Green Trust Alliance (GTA), a nationally accredited land trust and public charity dedicated to accelerating large-scale conservation, received $1.39 million in NJDEP funding to implement green infrastructure improvements at Pinelands Regional High School in Tuckerton, New Jersey. This initiative targets the Tuckerton Creek watershed, which drains into Tuckerton Creek and ultimately flows into Barnegat Bay—a critical estuary spanning 33 municipalities in Ocean County and four in Monmouth County. The retrofit will transform the school’s stormwater detention basin into a multi-functional system that mimics natural hydrology, enhances flow control, and improves water quality locally and in the larger Barnegat Bay watershed.
Working with GTA and GreenVest, Princeton Hydro is serving as the design engineer, applying nature-based engineering and ecological restoration techniques to intercept, evapotranspire, and infiltrate stormwater runoff at its source. In addition to its technical objectives, the effort includes a strong community engagement component and an educational platform for students. By bringing green infrastructure into the school environment, the initiative provides hands-on experience with water resources, stormwater management, and ecological engineering, help to build STEM skills while fostering a deeper connection to the surrounding landscape and an understanding of how natural systems work together to support environmental and community health.
Princeton Hydro also assisted several of these partners in developing successful NJDEP Section 319(h) grant applications, providing technical documentation, conceptual designs, and pollutant load reduction estimates to strengthen the proposals.
To date, the Murphy Administration has awarded more than $33M in Water Quality Restoration grants to improve the health of waterways in all corners of the state. Click here to read about all the 2025 grant funding recipients and their innovative projects.
As NJDEP Environmental Protection Commissioner Shawn M. LaTourette noted in the department's press release, “Enhancing the ecological health of our lakes, rivers, streams and coastal waters has long been a priority of the Murphy Administration. The Department of Environmental Protection is pleased to award these grants that will help our partners advance a variety of strategies to improve the health of these waterways and enhance the quality of life in our communities.”
We are proud to play a continued role in advancing that mission: helping communities implement practical, data-driven solutions that make a measurable difference for New Jersey’s waterways and the people who depend on them. Click here to learn more about our work to protect natural habitat and restore water quality throughout the New Jersey.
As we reflect on the winter of 2023-2024, it's evident that New Jersey experienced another unusually mild season, mirroring the winter of 2022-2023. Notably, Lake Hopatcong, located in Sussex and Morris Counties, remained virtually ice-free throughout the winter, with only a brief period of minor ice formation in early January. This pattern was not isolated to Lake Hopatcong; many lakes across the state and the broader Mid-Atlantic region exhibited similar ice-free conditions. Such conditions can lead to increased algal and plant growth earlier in the year.
Adding to this, from January to early June 2024, 15 of New Jersey's 21 counties recorded precipitation levels 26% to 50% higher than their long-term averages. The remaining six counties, predominantly in the southern part of the state, had precipitation increases of 11% to 25% above their long-term normals. This heightened precipitation is significant as it can transport nutrients, most notably phosphorus and nitrogen, into water bodies, potentially fueling the growth of algae.
Compounding these factors, long-range climate models and trends suggest that the summer of 2024 could rank among the hottest on record. The combination of a mild winter, increased precipitation, and anticipated high summer temperatures sets the stage for conditions similar to those experienced in 2019, a year marked by widespread harmful algal blooms (HABs) in numerous lakes.
HABs, characterized by rapid overgrowths of cyanobacteria, present serious challenges to water quality and aquatic ecosystems. Cyanobacteria, or blue-green algae, naturally occur in aquatic environments but can proliferate rapidly under warm, nutrient-rich conditions. These blooms pose risks to human health, wildlife, aquatic species, local economies, and the overall ecological balance. The interplay between climate change and HABs is undeniable: rising temperatures and altered precipitation patterns foster conditions that exacerbate bloom occurrences.
Given these circumstances, it is crucial for lake managers and water utilities to adopt proactive measures. Early and consistent sampling efforts can detect cyanobacteria and akinetes, dormant spores that contribute to bloom formation. Additionally, reducing nutrient inputs, particularly phosphorus, into waterways is essential to prevent HABs. Princeton Hydro strongly recommends that lake managers, water utilities, and concerned community members closely monitor their lakes, reservoirs, and riverways to stay as proactive as possible in managing these valuable resources.
By raising awareness, fostering collaboration, and implementing effective strategies, we can work towards safeguarding the health and sustainability of our freshwater ecosystems. Together, we can address the challenges posed by HABs and protect the integrity of our water bodies. For more information about HABs, click here.
Dr. Fred Lubnow, Princeton Hydro’s Senior Technical Director, Ecological Services, is an expert in aquatic and watershed management, restoration ecology, community and ecosystem ecology, and the use of benthic macroinvertebrate and fish in-stream bioassessment protocols. Dr. Lubnow has managed hundreds of lake projects and provides technical expertise for a variety of lake and watershed restoration projects.
His experience in lake and reservoir restoration includes the design and implementation of dredging, aeration, chemical control of nuisance species, nutrient inactivation (i.e. alum) and biomanipulation. His experience in watershed restoration includes the design and implementation of structural Best Management Practices (BMPs), the development of Total Maximum Daily Load (TMDL) pollutant budgets, and the design, implementation and analysis of watershed-based monitoring programs.
400 native plants were installed along the western shoreline of Memorial Pond in Mount Arlington, New Jersey. The planting was completed in one day by a team of 20+ volunteers, staff members from Mt. Arlington Department of Public Works (DPW), Lake Hopatcong Foundation, Lake Hopatcong Commission, Princeton Hydro, and a generous community member who volunteered his excavating equipment (and time).
The planting initiative aims to prevent shoreline erosion, promote the growth of native species, increase wildlife habitat, and improve the water quality of Memorial Pond and Lake Hopatcong. Funding for this project was secured through a grant from the New Jersey Department of Environmental Protection, awarded to the Lake Hopatcong Commission in partnership with the Lake Hopatcong Foundation.
Memorial Pond is a 0.3-acre stormwater runoff basin that gradually releases into Glen Brook, which then flows into Lake Hopatcong. The pond receives sheet flow of stormwater from the adjacent road, which contributes to nutrient and sediment loading, thus locally reducing water quality in Memorial Pond and ultimately the waters of Lake Hopatcong.
Memorial Park, which includes Memorial Pond and Glen Brook, was identified by Princeton Hydro and the Lake Hopatcong team as a priority site for improvement, targeting initiatives that reduce pollutants and excessive nutrients entering into Lake Hopatcong.
Additionally, the pond’s steeply-sloped shoreline was bare and only stabilized with large rocks at the base of the banks. In the absence of stabilizing vegetation, the pond’s banks were experiencing erosion, and there was some concern about a few mature trees along the shoreline potentially falling into the pond.
The photos above were taken in April 2023 before the planting initiative.
The plant selection and layout were designed taking into account the steep slope and presence of mature, existing trees as well as focusing on regionally native plant species that will thrive and help stabilize the eroding shoreline. The planting team, led by Princeton Hydro Landscape Architect Jamie Feinstein, RLA and Aquatics Project Manager Pat Rose, was given precise instructions on how to install the plants to eliminate washouts and ensure the root systems can embrace the soil and hold it in place.
A variety of native herbaceous plants and shrubs were chosen for the site, including pennsylvania sedge, slender mountain mint, blue flag iris, sweet azalea, smooth hydrangea, and maple-leaved viburnum.
The plants will help reduce stormwater flow, absorb excess nutrients, prevent erosion, and ultimately decrease sedimentation to the pond, while creating a visually pleasing addition to the park and providing a habitat for pollinators and birds. Overall, this project promotes a healthier and more balanced ecosystem in Memorial Park.
The photos above were taken in July 2023 immediately after the planting initiative.
The installation of these beneficial plants is part of a series of water quality initiatives on Lake Hopatcong funded by a NJDEP Freshwater Harmful Algal Bloom (HAB) Prevention & Management Grant and 319(h) Grant awarded to Lake Hopatcong Commission in partnership with the Lake Hopatcong Foundation.
Additional initiatives included in the watershed implementation and HABs management plan are, the installation of:
floating wetland island (FWI), which are a low-cost, effective green infrastructure solution designed to mimic natural wetlands in a sustainable, efficient, and powerful way. FWIs improve water quality by assimilating and removing excess nutrients; provide valuable ecological habitat for a variety of beneficial species; help mitigate wave and wind erosion impacts; provide an aesthetic element; and add significant biodiversity enhancement within open freshwater environments;
biochar filtration bags, which improve water quality by removing phosphorus from waterbodies. Biochar can be placed in floatation balls, cages, or sacks, which are then tethered along the shoreline and in critical locations throughout the waterbody; and
nanobubble aeration system, which increases the concentrations of dissolved oxygen in the water, prevents stagnation of water, increases circulation, disrupts thermal stratification which provides “through-column” mixing, and minimizes the occurrence of HABs.
“Paired with biochar filters attached to buoys in the pond and continued monitoring and maintenance of the plantings by the DPW, these steps will set a healthy precedent for what can be achieved through working together with funders, local partners, science, and landscape architecture,” said Feinstein, who sourced plant material, provided logistics and co-led the planning and volunteer planting event along with Rose.
Princeton Hydro's Landscape Architect, Cory Speroff PLA, ASLA, CBLP, designed the planting plan, and Will Kelleher and Jackson Tilves from the Aquatics Team participated in the plant installation event with Feinstein.
Princeton Hydro is also authoring and supplying a maintenance manual that provides guidance on seasonal care of the plantings, when to remove the herbivory protection fencing, pruning, watering, and other activities that support the long term success of the planting initiative.
“This collaborative effort to enhance water quality serves as a prime example of how seemingly simple actions can have a meaningful impact on safeguarding our water resources for the benefit of future generations,” said the Lake Hopatcong Foundation.
The photos above from left to right: June 2023 before the planting; July 2023 during the planting (photo by Lake Hopatcong Foundation Executive Director Kyle Richter); and July 2023 immediately after the planting.
Princeton Hydro has been working on Lake Hopatcong, New Jersey’s largest Lake, for 30+ years, restoring the lake, managing the watershed, reducing pollutant loading, and addressing invasive aquatic plants and nuisance algal blooms. To read about some of the other projects we’ve recently worked on at Lake Hopatcong, click here.
Our lakes in New Jersey are an invaluable resource for clean drinking water, outdoor recreation, and agriculture and provide habitat for aquatic flora and fauna. Home to about 1,700 lakes, the “Garden State” is also the most densely populated state. Excess nutrients from fertilizers, roadway pollutants, overdevelopment, and failing septic systems can end up in our lakes and impair water quality. Larger rain events can also cause erosion and instability of streams, adding to the influx of more excess nutrients to our lakes and ponds. Changes in hydrology, water chemistry, biology, and/or physical properties in these complex ecosystems can have cascading consequences that can alter water quality and the surrounding ecosystem. For example, excess nutrients can fuel algal and plant growth in lakes and lead to issues like harmful algal blooms (HABs) or fish kills.
In order to ensure that we protect the overall health of our local waterbodies, it’s important that we look beyond just the lake itself. Implementing holistic watershed-based planning is a critical step in managing stormwater runoff, preventing the spread of HABs, and maintaining water quality. A watershed management plan defines and addresses existing or future water quality problems from both point sources and nonpoint sources of pollutants*. This approach addresses all the beneficial uses of a waterbody, the criteria needed to protect the use, and the strategies required to restore water quality or prevent degradation. When developing a watershed plan, we review all the tools in the toolbox and recommend a variety of best management practices to prevent nutrients from entering lakes or streams. Options include short- and long-term solutions such as green stormwater infrastructure, stream bank stabilization, and stormwater basin retrofits.
To reduce nutrient availability in lakes, one innovative tool in our toolbox is floating wetland islands (FWIs). FWIs are a low-cost, effective green infrastructure solution that are designed to mimic natural wetlands in a sustainable, efficient, and powerful way. They improve water quality by assimilating and removing excess nutrients; provide valuable ecological habitat for a variety of beneficial species; help mitigate wave and wind erosion impacts; provide an aesthetic element; and add significant biodiversity enhancement within open freshwater environments. FWIs are also highly effective in a range of waterbodies from big to small, from deep to shallow.
Typically, FWIs consist of a constructed floating mat, usually composed of woven, recycled plastic material, with vegetation planted directly into the material. The islands are then launched into the lake and anchored in place, and, once established, require very little maintenance.
It estimated that one 250-square-foot FWI has a surface area equal to approximately one acre of natural wetland. These floating ecosystems can remove approximately 10 pounds of phosphorus each year. To put that into perspective, one pound of phosphorus can produce 1,100 pounds of algae each year, so each 250-square-feet of FWI can potentially mitigate up to 11,000 pounds of algae.
In addition to removing phosphorus that can feed nuisance aquatic plant growth and algae, FWIs also provide excellent refuge habitat for beneficial forage fish and can provide protection from shoreline erosion.
Princeton Hydro has been working with Lake Hopatcong, New Jersey’s largest Lake, for 30+ years, restoring the lake, managing the watershed, reducing pollutant loading, and addressing invasive aquatic plants and nuisance algal blooms. Back in 2012, Lake Hopatcong became the first public lake in New Jersey to install FWIs. In the summer of 2022, nine more FWIs were installed in the lake with help from staff and volunteers from the Lake Hopatcong Foundation, Lake Hopatcong Commission, and Princeton Hydro. The lake’s Landing Channel and Ashley Cove were chosen for the installations because they are both fairly shallow and prone to weed growth. The installation of these floating wetland islands is part of a series of water quality initiatives on Lake Hopatcong funded by a NJDEP Harmful Algal Bloom Grant and 319(h) Grant awarded to Lake Hopatcong Commission and Lake Hopatcong Foundation.
Princeton Hydro partnered with the Greenwood Lake Commission (GWLC) on a FWI installation in Belcher's Creek, the main tributary of Greenwood Lake. The lake, a 1,920-acre waterbody located in both New Jersey and New York, is a highly valued ecological, economical, and recreational resource. The lake also serves as a headwater supply of potable water that flows to the Monksville Reservoir and eventually into the Wanaque Reservoir, where it supplies over 3 million people with drinking water.
The goal of the FWI Installation was to help decrease total phosphorus loading, improve water quality, and create important habitat for beneficial aquatic, insect, bird, and wildlife species. The project was partially funded by the NJDEP Water Quality Restoration Grants for Nonpoint Source Pollution Program under Section 319(h) of the federal Clean Water Act. GWLC was awarded one of NJDEP’s matching grants, which provided $2 in funding for every $1 invested by the grant applicant.
Measuring 630+ acres, Harveys Lake is the largest natural lake (by volume) in Pennsylvania and is one of the most heavily used lakes in the area. It is classified as a high quality - cold water fishery habitat (HQ-CWF) and is designated for protection under the classification. Since 2002, The Borough of Harveys Lake and Harveys Lake Environmental Advisory Council has worked with Princeton Hydro on a variety of lake management efforts focused around maintaining high water quality conditions, strengthening stream banks and shorelines, and managing stormwater runoff. Five floating wetland islands were installed in Harveys Lake to assimilate and reduce nutrients already in the lake. The islands were placed in areas with high concentrations of nutrients, placed 50 feet from the shoreline and tethered in place with steel cables and anchored. The FWIs were funded by PADEP.
Working with the Deal Lake Commission (DLC), Princeton Hydro designed and installed 12 floating wetland islands at two lakes in Asbury Park, NJ. In order to complete the installation of the floating wetland islands, our team worked with the DLC to train and assist over 30 volunteers to plant plugs in the islands and launch them into the two lakes. Our experts helped disseminate knowledge to the volunteers, not only about how to install the floating wetland islands, but how they scientifically worked to remove excess nutrients from the water. With assistance from Princeton Hydro, DLC acquired the 12 floating islands – six for Wesley Lake and six for Sunset Lake – through a Clean Water Act Section 319(h) grant awarded by NJDEP.
In addition to the direct environmental benefits of FWIs, the planting events themselves, which usually involve individuals from the local lake communities, have long-lasting positive impacts. When community members come together to help plant FWIs, it gives them a deepened sense of ownership and strengthens their connection to the lake. This, in turn, encourages continued stewardship of the watershed and creates a broader awareness of how human behaviors impact the lake and its water quality. And, real water quality improvements begin at the watershed level with how people treat their land.
For more information on watershed planning or installing FWI in your community, click here to contact us. To learn more about ANJEC, go here.
The Musconetcong River begins at New Jersey’s largest lake, Lake Hopatcong, and flows southwest for 42 miles before emptying into the Delaware River. At the headwaters in Lake Hopatcong, the community has been battling with harmful algal blooms (HABs). HABs can cause significant water quality issues in lakes and ponds, often forming a visible and sometimes odorous scum on the surface of the water. Blooms are primarily caused by warmer temperatures and increased amounts of nutrients (i.e., nitrogen and phosphorus) from stormwater runoff.
In 2019, the local community suffered immensely from HABs, which was the most prolific bloom the lake has experienced over the last two decades, resulting in public health advisories to be issued for recreation on the lake. Because Lake Hopatcong is a popular summer vacation destination, this outbreak unfortunately stunted the local economy, restricted recreational usage of the lake, and impacted fish and wildlife.
The Lake Hopatcong Commission and Lake Hopatcong Foundation, in partnership with municipalities, counties, the state, local groups like the Musconetcong Watershed Association, and Princeton Hydro, have been working to improve water quality for years by prioritizing stormwater mitigation and septic management policies within the watershed. So why was the summer of 2019 so intense?
Princeton Hydro scientists have been collecting water quality data in Lake Hopatcong for 30 years. This includes dissolved oxygen, pH, and temperature, as well as concentrations of total suspended solids, total phosphorus, nitrate‐N, ammonia‐N and chlorophyll a, and various biological factors. There are not many lakes in New Jersey that have such a robust and consistent public dataset, which presents a rare opportunity to study long-term trends. We dove a little deeper into this information to see what many have caused the 2019 blooms.
We analyzed a statistically significant dataset of surface water temperatures and found that average July surface temperatures in Lake Hopatcong have been steadily increasing over time. We also have 20+ years of observational data that documents an increase in frequency, duration, and magnitude of HABs over the same time period. In fact, HABs have recently persisted all the way into the winter months, enabling “green ice” to form on the lake surface, as observed in December 2020.
In summer of 2019, the Lake Hopatcong region was hit with a dramatic amount of rainfall. These weather patterns resulted in some of the highest early summer total phosphorus (TP) concentrations in Lake Hopatcong in over 20 years. The mean June TP concentration was 0.043 mg/L; the last time it exceeded 0.04 mg/L was in 1999. In order to have acceptable water quality conditions in the lake, the mean TP concentrations should be at 0.03 mg/L or lower.
It has been well documented that phosphorus is the primary limiting nutrient in Lake Hopatcong. Meaning, a slight increase in phosphorus can result in a substantial increase in algal and/or aquatic plant biomass. The water quality analysis identified the cause for the HABs (the high frequency of storms in June 2019 transporting nutrients, in particular phosphorus, to the lake) and identified why they persisted over the growing season (internal phosphorus loading).
Climate change is leading to more frequent, more intense rainstorms that transport run-off pollutants into waterways, coupled with hotter days to warm the water. The latest Intergovernmental Panel on Climate Change (IPCC) report, “AR6 Climate Change 2021: The Physical Science Basis,” confirmed that human influence has warmed the atmosphere, ocean, and land, and that this human-induced climate change is already affecting many weather and climate extremes in every region across the globe. It predicts, “increases in the frequency and intensity of hot extremes, marine heatwaves, and heavy precipitation, agricultural and ecological droughts in some regions, and proportion of intense tropical cyclones, as well as reductions in Arctic sea ice, snow cover and permafrost.” In the Mid-Atlantic region of the U.S., most climate models indicate that the landscape will become warmer and wetter.
Looking at our observations and 30-year dataset for Lake Hopatcong, our preliminary analysis shows that climate change — increased precipitation (which flushed the phosphorus into the lake) followed by intense heat to warm surface water temperatures — was a significant variable that led to the devastating HABs at Lake Hopatcong in 2019.
Other communities have experienced similar trends too. According to the U.S. Environmental Protection Agency, HABs have now been observed in all 50 states, ranging from large freshwater lakes, to smaller inland lakes, rivers, and reservoirs. Our neighbors in Upstate New York suffered from 1,000+ HAB occurrences during the 2019 season, including a HAB that covered 600+ square miles of Lake Erie causing beach closures and fish kills.
A study recently published in Nature journal reviewed three decades of high-resolution satellite data for 71 large lakes globally and determined that “peak summertime bloom intensity has increased in most (68%) of the lakes studied, revealing a global exacerbation of bloom conditions.” The study called for water quality management efforts to better account for the interactions between climate change and local hydrological conditions.
We are witnessing these impacts firsthand at Lake Hopatcong and within the Musconetcong River Watershed. And, according to the IPCC report, these climate change-induced instances (i.e. intense rainfall followed by intense heat) may become even more frequent. To further understand the connection between climate change and HABs at Lake Hopatcong, Princeton Hydro is conducting a more rigorous study that includes more distinct data. We hope this will provide some insight on how to manage expected climate impacts in lakes and watersheds.
While the IPCC report conclusions may be depressing, there is still much we can do at both a global and local level to limit future climate change. The key here is limiting cumulative CO2 (carbon dioxide) and CH4 (methane) emissions and quickly reaching (at least) net zero CO2 emissions. And, to specifically reduce occurrences of HABs While the IPCC report conclusions may be depressing, there is still much we can do at both a global and local level to limit future climate change. The key here is globally limiting cumulative CO2 (carbon dioxide) and CH4 (methane) emissions and quickly reaching (at least) net zero CO2 emissions. And, to specifically reduce occurrences of HABs fueled by climate change in Lake Hopatcong, eliminating sources of phosphorus from entering the lake is critical. So what can we do in the Musconetcong River Watershed?
In 2019, NJ Department of Environmental Protection committed $13.5 million via their Water Quality Restoration Grant programs for local projects that aim to improve water quality in New Jersey’s lakes and ponds. The Lake Hopatcong Commission landed a $500k grant via the program to evaluate and implement a variety of innovative, nearshore projects at Lake Hopatcong. Projects included performing an alternative non-copper-based algaecide treatment and one of the largest nutrient PhosLock treatments in the Northeast on the lake as well as the installation of Biochar bags, near-shore aeration systems, and floating wetland islands.
This could not be possible without the help of all project partners including Lake Hopatcong Foundation, Morris County, Sussex County, Jefferson Township, Borough of Hopatcong, Borough of Mt. Arlington, and Roxbury Township, who collectively contributed over $330k in match support. The Lake Hopatcong Commission also landed a subsequent $206,000 grant via NJDEP’s 319 program a few months later, with $44,000 in match support from the four municipalities and Lake Hopatcong Foundation and Commission, for the design and implementation of four in-lake/watershed projects to protect Lake Hopatcong's water quality.
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The results of these projects were significant. Over the last two years, the mean June TP concentrations were lower than 2019 (0.033 mg/L in 2020 and 0.020 mg/L in 2021). These in-lake and watershed efforts have had a positive impact on reducing available phosphorus.
Just this month, Lake Hopatcong Commission landed another $480k from a National Fish and Wildlife Foundation Delaware Watershed Conservation Fund grant, which was backed with $489k more in match support from Lake Hopatcong Commission, Lake Hopatcong Foundation, Musconetcong Watershed Association, NJDEP, Borough of Hopatcong, Township of Roxbury, Mount Arlington Borough, Morris and Sussex Counties, Lake Hopatcong Historical Museum, Rutgers University, NJ Highlands Council, and Princeton Hydro. The project team will design and implement three streambank stabilization projects in the watershed, which were identified as priority projects in the 2021 Upper Musconetcong River Watershed Implementation Plan.
“Managing loads of phosphorous in watersheds is even more important as the East Coast becomes increasingly warmer and wetter thanks to climate change. Climate change will likely need to be dealt with on a national and international scale. But local communities, groups, and individuals can have a real impact in reducing phosphorous levels in local waters.” Dr. Fred Lubnow, Director of Aquatics for Princeton Hydro
“Managing loads of phosphorous in watersheds is even more important as the East Coast becomes increasingly warmer and wetter thanks to climate change. Climate change will likely need to be dealt with on a national and international scale. But local communities, groups, and individuals can have a real impact in reducing phosphorous levels in local waters.”
To read the full article in the Musconetcong Watershed Association's "Instream Update" eNewsletter, click here.
The Musconetcong Watershed Association is an independent, non-profit organization dedicated to protecting and improving the quality of the Musconetcong River and its watershed, including its natural and cultural resources. Since 2003, Princeton Hydro has been working with MWA in the areas of river restoration, dam removal, and engineering consulting. Click here to read our Client Spotlight blog featuring MWA’s Executive Director Cindy Joerger and Communications Coordinator Karen Doerfer.
To prevent harmful algal blooms (HABs) in New Jersey’s largest lake, a clay-based nutrient inactivating technology called Phoslock, is being applied in Lake Hopatcong this week. This is the largest Phoslock treatment to occur in the Northeastern U.S. The Phoslock treatment, which is happening in the southern end of the lake called Landing Channel, is expected to take approximately one week depending on the weather conditions.
Over the course of the 2019 summer season, Lake Hopatcong suffered from large-scale and persistent HABs causing local and county health agencies to close off all beaches and issue advisories over large sections of the lake. These unprecedented conditions had significant negative impacts on the ecological, recreational, and economic resources of the lake and region. In order to combat HABs in this upcoming 2020 summer season, the Lake Hopatcong Commission has partnered with the Lake Hopatcong Foundation, four municipalities (Jefferson, Hopatcong, Mt. Arlington, and Roxbury), two counties (Morris and Sussex), and their environmental consultant, Princeton Hydro, to develop both short- and long-term lake management strategies.
“The negative effects of HABs in our lake last year were numerous, widespread, and in some cases devastating,” recalled Donna Macalle-Holly of Lake Hopatcong Foundation. “It is imperative for every stakeholder to pool our resources to keep it from happening again. Collaboration is the only way to protect public health, as well as the health of New Jersey’s largest lake.”
In an effort to evaluate a variety of innovative in-lake and watershed-based measures to prevent, mitigate, and/or control harmful algal blooms in Lake Hopatcong, the Lake Hopatcong Commission was awarded a $500k grant as part of New Jersey Department of Environmental Protection’s (NJDEP) new $13.5M initiative to reduce and prevent future harmful algal blooms in New Jersey. In addition to the $500k grant, the aforementioned local government and nonprofit stakeholders provided $330k in matching funds to implement and evaluate a variety of ways to address HABs in Lake Hopatcong.
“Our lake community cannot sustain another year like 2019,” said Lake Hopatcong Commission Chairman Ron Smith. “Since the news of our grant award in early March, we have been working with our partners to make sure the projects are implemented in time for the 2020 season.”
This week, the water resource engineering and natural resource management firm, Princeton Hydro—a lake management consultant to Lake Hopatcong for over two decades—is implementing the first and largest innovative measure as part of the NJDEP HABs grant-funded project. This involves treating 50 acres of the southern end of the lake with Phoslock, a clay-based product that inactivates phosphorus in both the water column and the sediments, making this critical nutrient unavailable for algal growth. The Phoslock treatment, which requires proper permitting by NJDEP, is applied as a slurry and will be distributed from a boat. The slurry will temporarily make the water appear turbid, but should disperse approximately two to six hours after each treatment.
“We are expecting the Phoslock treatment to limit the growth of algae and therefore reduce the occurrence of harmful algal blooms in the lake this summer, keeping it open for recreation and business,” said Dr. Fred Lubnow, Director of Aquatic Resources at Princeton Hydro and leading HABs expert. “If this technology is deemed successful and cost-effective in Lake Hopatcong, we could set the precedent for large-scale HABs prevention in other lakes throughout New Jersey, and even across the nation.”
Developed by the Australian national science agency CSIRO, Phoslock is frequently used to strip the water column of dissolved phosphorus, as well as to inactivate phosphorus generated from deep, anoxic sediments. Recently, at a smaller scale, it has been shown to inactivate the mobilization of phosphorus from shallow sediments where there is a mobilization of phosphorus from both chemical and biological processes.
Algae uses phosphate, the biologically available form of phosphorus, as a food source to grow. When there is an excessive amount of phosphorus in a lake, algal growth can be dense and can negatively affect water quality. This excessive plant growth, caused by eutrophication, can both cause a lack of oxygen available, leading to fish kills, as well as produce harmful algal blooms with cyanotoxins, which are harmful to humans and pets.
After Phoslock is applied, it sinks through the water column, binding phosphate as it moves towards the sediment. Once settled at the bottom of the lake, it forms a very thin layer and continues to bind phosphate released from the sediment, thus controlling the release of phosphorus into the lake. One pound of phosphorus has the potential to generate up to 1,100 lbs of wet algae biomass. However, 1.1 tons of Phoslock is capable of removing 24 pounds of phosphorus -- that’s over 26,000 lbs of wet algae biomass not growing in the lake for every 1.1 ton of Phoslock applied. In turn, Phoslock’s ability to suspend biologically available phosphorus is therefore a major step towards improving a lake’s water quality.
As part of the NJDEP HABs grant funding, the stakeholder group will be evaluating the relative effectiveness of this treatment strategy. Because of its shallow depth and separation from the main lake, the Landing Channel area was a good candidate for evaluation of this technology. Princeton Hydro will conduct pre- and post-treatment monitoring of the Phoslock treatment area in order to conduct an objective evaluation of the cost effectiveness of the treatment as a means of preventing the development and/or mitigation of HABs. If the study indicates that Phoslock is a cost-effective treatment, the Lake Hopatcong Commission may consider additional trials in other sections of the lake, if funding is available.
The Lake Hopatcong Foundation (LHF) recently launched its newest initiative - a floating classroom. The custom-built 40-foot education vessel, named 'Study Hull', gives students an interactive, hands-on education experience to explore Lake Hopatcong, learn about freshwater ecology, and learn how to protect the watershed.
During its maiden voyage field trip, which was held on May 21, fourth-graders from Nixon Elementary and Kennedy Elementary schools utilized the boat’s laboratory instruments to study water hydrology, temperatures, plankton, and dissolved oxygen levels. They performed a series of tests and experiments designed to help them learn about the general health of the lake. They used Secchi Disks to determine the depth to which light is able to penetrate the water's surface. They also learned about runoff and nonpoint source pollutants, how to protect the lake’s water quality, and how to be good stewards of the water.
Princeton Hydro helped the LHF design a teaching curriculum on water quality. Dr. Jack Szczepanski, Senior Aquatics Scientist, and Christopher L. Mikolajczyk, CLM, Senior Project Scientist, trained the staff and volunteers on the curriculum and demonstrated various water quality monitoring techniques that can be conducted with the students.
“We’re really proud to be a part of this exciting initiative,” said Mikolajczyk. “It’s really important to get kids interested in science at an early age and teach them about their surrounding environment – where their drinking water comes from, how it gets polluted, the impacts pollution has on the lake’s ecosystem, and what steps can be made to protect the lake’s water quality. We're hoping the floating classroom field trip program will make a lasting, valuable impression with these kids.”
In the first year of operation it is expected that the Study Hull will host 1,000 fourth grade students. The long-term goal is to develop lesson plans for students in every grade from kindergarten through high school. Starting in July, the LHF is also offering the public tours of the floating classroom on Mondays at Hopatcong State Park.
The purchase of the floating classroom was made possible by financial support from USATODAY Network’s “A Community Thrives” program, which awarded the LHF with a $50,000 grant. The program recognizes three categories: arts and culture, education, and wellness. In each category, the first place winner received a $100,000 grant and the second and third place winners received $50,000 grants. The James P. Verhalen Family Foundation and the Szigethy Family also provided significant donations to help bring the floating classroom to life.
The LHF and Princeton Hydro are longtime partners. Starting back in 1983, Princeton Hydro’s Dr. Stephen Souza conducted the USEPA funded Diagnostic Feasibility study of the lake and then authored the Lake Hopatcong Restoration Plan. That document continues to be the backbone of why and how to restore the lake, manage the watershed, reduce pollutant loading, and address invasive aquatic plants and nuisance algae blooms.
Lake Hopatcong has one of the longest, continuous, long-term ecological databases in New Jersey; almost 30 years of consistently collected water quality data. The data is crucial in assessing the overall ecological health of the lake and proactively guiding its management, identifying and addressing emerging threats, documenting project success (a mandatory element of funding initiatives) and confirming compliance with New Jersey State Water Quality standards.
Princeton Hydro’s most recent work for Lake Hopatcong includes the implementation of green infrastructure stormwater management measures, installation of floating wetland islands to improve water quality, and invasive aquatic plant species management programs, community educational training, and surveys.
For more information about the Lake Hopatcong Foundation or the floating classroom, click here. For more information about Princeton Hydro’s lake management services, go here.
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