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The towering 25-foot concrete structure, originally built for aesthetic purposes on a tributary to the Hudson River, has been impairing aquatic life and causing an array of negative environmental impacts since its construction in the early 1900s. Now, it is the focus of a project that promises to restore vital aquatic habitats. Join us as we take a deeper look at the Maiden Lane Dam Removal project, an initiative that has been in the planning phase for nearly five years. Maiden Lane Dam Located in the Town of Cortlandt on Furnace Brook, a tributary of the Hudson River, the Maiden Lane Dam was originally built by the former owners of McAndrews Estate. Unlike many dams throughout the country constructed with the primary goals of flood control, hydroelectric power, agricultural irrigation, or navigation of boats, the Maiden Lane Dam was built for aesthetic purposes. Yet the dam's impact extended well beyond its appearance. The Maiden Lane Dam is the very first dam that fish and aquatic species encounter on Furnance Brook while attempting to travel up the Hudson River to reach foraging habitats and ancestral spawning grounds. The antiquated, unused dam poses a variety of risks to the wildlife restricted by the dam, people who live and recreate near the dam, and the environment surrounding the dam. The Dam Removal Project Takes Shape McAndrews Estate, along with the dam, was abandoned in the 1960s, and subsequently, Westchester County Parks assumed control of it. Shortly afterwards, the property was condemned. In 2021, Princeton Hydro secured a contract with Westchester County to develop and finalize the dam removal engineering plans, secure permitting, and facilitate construction bid procurement. The project work also entailed collecting and analyzing sediment samples, conducting geomorphic assessments, and completing an in-depth hydraulic and hydrologic analysis focusing on potential flooding impacts. The collaboration with key stakeholders, including NYSDEC, Westchester County, and the Town of Cortlandt, ensured the feasibility of this ambitious dam removal endeavor. The collaboration and careful planning set the stage for the much-anticipated removal of the Maiden Lane Dam. A Hopeful Future for Hudson River Valley The significance of this project cannot be overstated. Beyond its historical and ecological significance, the Maiden Lane Dam removal will reconnect approximately 1.5 miles of habitat for fish and other aquatic species. It represents a promising chapter in the ongoing efforts to revitalize Hudson River Valley streams and conserve the region's diverse fish and wildlife. As we eagerly await the completion of the Maiden Lane Dam removal, the vision of restored aquatic habitats and thriving ecosystems shines brightly on the horizon. The journey of the Maiden Lane Dam Removal project is a testament to dedication, collaboration, and the unwavering commitment to the preservation of our natural environment. Keep the Dam Removal Conversations Flowing Princeton Hydro team members Jake Dittes, PE and Duncan Simpson, PWS presented on Hudson Valley Dam removal during the 2023 National Stream Restoration Conference, hosted by the Resource Institute, a nonprofit organization dedicated to the restoration of America's precious waterways. The event, themed "Stream Restoration 2023: Finding Common Ground,” served as an inspiring backdrop for the broader narrative of stream restoration, showcasing the importance of projects like the Maiden Lane Dam removal in preserving our natural treasures. The Maiden Lane Dam Removal is part of a larger effort, led by Riverkeeper, to restore migratory fish pathways and fisheries in the Hudson River Watershed. Princeton Hydro has designed, permitted, and/or overseen the removal of 80+ small and large dams in the Northeast. To learn more about fish passage and dam removal efforts in the Hudson River Valley, click here. To learn more about our engineering services, click here. [post_title] => Breaking Barriers: Maiden Lane Dam Removal Project [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => breaking-barriers-maiden-lane-dam-removal-project [to_ping] => [pinged] => [post_modified] => 2024-01-17 17:37:35 [post_modified_gmt] => 2024-01-17 17:37:35 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=13748 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 10290 [post_author] => 1 [post_date] => 2022-02-17 19:39:19 [post_date_gmt] => 2022-02-17 19:39:19 [post_content] => The Aquetong Creek Restoration Project is situated within the former basin of Aquetong Lake, which was a 15- acre impoundment formed in 1870 by the construction of an earthen dam on Aquetong Creek. The cold-water limestone spring, which flows at a rate of about 2,000 gallons per minute at approximately 53ºf, is known to be the largest of its kind in the 5-county Philadelphia region, and one of the largest in the state of Pennsylvania. In 2015, the Township of Solebury commenced the restoration of Aquetong Spring Park, first with a dam breach followed by a large stream restoration, reforestation, and invasive species removal. In September, the park was officially reopened to the public following a ribbon cutting ceremony. The event featured a blessing from the Lenni-Lenape Turtle Clan, the original inhabitants of the land. SITE HISTORY Prior to European settlement, the Lenni-Lenape Tribe inhabited a village close to the spring and designated the spring “Aquetong”, meaning “at the spring among the bushes." After an outbreak of smallpox, however, the tribe abandoned the village. William Penn acquired Aquetong Spring in the early 1680’s as part of his peaceful treaty with Lenni-Lenape. The park land transferred hands many times before it was owned by Aquetong Township. The dependability of the water flow made the Aquetong Creek an ideal location for mills. As of the early 1800’s, Aquetong Spring is known to have supplied enough water to turn two grist mills regularly throughout the year, and to have concurrently powered numerous mills including a paper mill, a fulling mill, two merchant mills, four sawmills, and an oil mill. Around 1870, the 15-acre Aquetong Lake was created by constructing a dam at the east end of the property. This provided additional power for the local mills and a recreation area for the public. A fish hatchery was constructed at the base of the spring outfall, portions of which can still be viewed today. Shad, brook trout, and terrapin turtles were raised in the hatchery, which was available for public viewing at a cost of 25 cents per person. Then, in 1993, the Pennsylvania Fish and Boat Commission acquired the property. A few years later, with the support of Bucks County Trout Unlimited, Solebury Township began negotiating to obtain ownership of the site. Around 1996, the State performed emergency repairs on the dam; a six-foot section of the outlet structure was removed in order to take pressure off the aging barrier. This lowered the level of the lake and added about 80 feet of wetlands to the western shoreline. However, it was recognized that a complete repair of the dam could cost over $1 million and might not be the best choice for the environment. In 2009, after almost 15 years of negotiations, Solebury Township gained control of the property, with the goal of preserving this important natural resource. It purchased the lake and surrounding properties from the state and obtained a 25-year lease. The Township’s total costs were substantially reduced because it received a large credit in exchange for its commitment to repair the dam in the future, as well as funding from the Bucks County Natural Areas Program toward the purchase. Following the purchase, the Township engaged in a five-year process of community outreach and consultation with environmental experts in which it considered alternatives for the Aquetong Lake dam. Choices included rebuilding the dam in its then-current form, creating a smaller lake with a cold-water bypass into Aquetong Creek, or breaching the dam and restoring a free-flowing stream. Ultimately, recognizing that the lake was a thermal reservoir which introduced warm water into Aquetong Creek and eventually into the streams and river, the Township decided to breach rather than restore the dam, and return the site to its natural state. [caption id="attachment_10303" align="aligncenter" width="832"] The Aquetong Creek restoration site is located in Solebury Township, Bucks County, PA, and encompasses the boundaries of the former Aquetong Lake. The Lake was a 15-acre impoundment formed in 1870 by the construction of an earthen dam on Aquetong Creek. The Creek flows approximately 2.5 miles from Ingham Spring to join with the Delaware River in New Hope, PA.[/caption] RESTORATION WORK The Aquetong Restoration Project got underway in 2015, and Solebury Township breached the historic mill dam in Aquetong Spring Park to convert the former lake into a natural area with a free-flowing, cold water stream capable of supporting native brook trout. After the dam breach, areas of active erosion were observed along the mainstem and a major tributary of Aquetong Creek. The steep, eroding banks, increased the sediment load to the Creek's sensitive aquatic habitat. As with most dam removal projects, a degree of stewardship is necessary to enhance the establishment of desirable, beneficial vegetation. Additionally, Solebury Township wanted to control invasive species in Aquetong Spring Park and replant the project area with native species. The Township secured funding to construct riparian buffers, implement streambank stabilization measures, establish trout habitat structures within the mainstem and its tributary, control invasive species, and implement a woodland restoration plan. The project was funded by a $250,000 grant from the PA Department of Conservation and Natural Resources, with an equal match from the Township. Additional grants for the project were provided by the PA Department of Community and Economic Development and the National Fish and Wildlife Foundation. Solebury Township contracted Princeton Hydro to design the stabilization of the stream channel and floodplains within the former impoundment, monitor the stream and wetlands before and after implementation, and obtain the permits for the restoration of the former impoundment. Princeton Hydro team members designed the restoration of the main channel and tributary to reduce channel and bank erosion while supporting the brook trout habitat. After gathering and reviewing the existing data for the site, Princeton Hydro conducted field investigations to inform and guide the final design including surveying cross sections and performing fluvial geomorphological assessments of the existing channel. Pebble counts were performed, cross sections were analyzed, and existing hydrological data was reviewed to inform the design. Simultaneously, an invasive species control and woodland restoration plan was developed for the park. Data collected from the site was used to develop a geomorphically-appropriate, dynamically-stable design. The proposed channel design included excavation of impounded sediment to create stable channel dimensions, the addition of gravel, cobble, and boulder substrate where original/existing channel substrates were absent or insufficient, and the installation of large wood features to create aquatic habitat and enhance stability of channel bed and banks. The banks and riparian corridor were vegetated with native seed, shrubs and trees to ultimately create a wooded, shaded riparian buffer. The design ultimately stabilized the streambanks with features that double as trout habitat and replanted the surrounding park with native vegetation. The project was replanted with an incredibly diverse set of native species that included:
An extraordinary effort is underway in the Hudson River Valley—the removal of the Maiden Lane Dam. The towering 25-foot concrete structure, originally built for aesthetic purposes on a tributary to the Hudson River, has been impairing aquatic life and causing an array of negative environmental impacts since its construction in the early 1900s. Now, it is the focus of a project that promises to restore vital aquatic habitats.
Join us as we take a deeper look at the Maiden Lane Dam Removal project, an initiative that has been in the planning phase for nearly five years.
Located in the Town of Cortlandt on Furnace Brook, a tributary of the Hudson River, the Maiden Lane Dam was originally built by the former owners of McAndrews Estate. Unlike many dams throughout the country constructed with the primary goals of flood control, hydroelectric power, agricultural irrigation, or navigation of boats, the Maiden Lane Dam was built for aesthetic purposes. Yet the dam's impact extended well beyond its appearance.
The Maiden Lane Dam is the very first dam that fish and aquatic species encounter on Furnance Brook while attempting to travel up the Hudson River to reach foraging habitats and ancestral spawning grounds. The antiquated, unused dam poses a variety of risks to the wildlife restricted by the dam, people who live and recreate near the dam, and the environment surrounding the dam.
McAndrews Estate, along with the dam, was abandoned in the 1960s, and subsequently, Westchester County Parks assumed control of it. Shortly afterwards, the property was condemned.
In 2021, Princeton Hydro secured a contract with Westchester County to develop and finalize the dam removal engineering plans, secure permitting, and facilitate construction bid procurement. The project work also entailed collecting and analyzing sediment samples, conducting geomorphic assessments, and completing an in-depth hydraulic and hydrologic analysis focusing on potential flooding impacts. The collaboration with key stakeholders, including NYSDEC, Westchester County, and the Town of Cortlandt, ensured the feasibility of this ambitious dam removal endeavor.
The collaboration and careful planning set the stage for the much-anticipated removal of the Maiden Lane Dam.
The significance of this project cannot be overstated. Beyond its historical and ecological significance, the Maiden Lane Dam removal will reconnect approximately 1.5 miles of habitat for fish and other aquatic species. It represents a promising chapter in the ongoing efforts to revitalize Hudson River Valley streams and conserve the region's diverse fish and wildlife.
As we eagerly await the completion of the Maiden Lane Dam removal, the vision of restored aquatic habitats and thriving ecosystems shines brightly on the horizon. The journey of the Maiden Lane Dam Removal project is a testament to dedication, collaboration, and the unwavering commitment to the preservation of our natural environment.
Princeton Hydro team members Jake Dittes, PE and Duncan Simpson, PWS presented on Hudson Valley Dam removal during the 2023 National Stream Restoration Conference, hosted by the Resource Institute, a nonprofit organization dedicated to the restoration of America's precious waterways. The event, themed "Stream Restoration 2023: Finding Common Ground,” served as an inspiring backdrop for the broader narrative of stream restoration, showcasing the importance of projects like the Maiden Lane Dam removal in preserving our natural treasures.
The Maiden Lane Dam Removal is part of a larger effort, led by Riverkeeper, to restore migratory fish pathways and fisheries in the Hudson River Watershed.
Princeton Hydro has designed, permitted, and/or overseen the removal of 80+ small and large dams in the Northeast. To learn more about fish passage and dam removal efforts in the Hudson River Valley, click here. To learn more about our engineering services, click here.
The Aquetong Creek Restoration Project is situated within the former basin of Aquetong Lake, which was a 15- acre impoundment formed in 1870 by the construction of an earthen dam on Aquetong Creek. The cold-water limestone spring, which flows at a rate of about 2,000 gallons per minute at approximately 53ºf, is known to be the largest of its kind in the 5-county Philadelphia region, and one of the largest in the state of Pennsylvania.
In 2015, the Township of Solebury commenced the restoration of Aquetong Spring Park, first with a dam breach followed by a large stream restoration, reforestation, and invasive species removal. In September, the park was officially reopened to the public following a ribbon cutting ceremony. The event featured a blessing from the Lenni-Lenape Turtle Clan, the original inhabitants of the land.
Prior to European settlement, the Lenni-Lenape Tribe inhabited a village close to the spring and designated the spring “Aquetong”, meaning “at the spring among the bushes." After an outbreak of smallpox, however, the tribe abandoned the village. William Penn acquired Aquetong Spring in the early 1680’s as part of his peaceful treaty with Lenni-Lenape. The park land transferred hands many times before it was owned by Aquetong Township.
The dependability of the water flow made the Aquetong Creek an ideal location for mills. As of the early 1800’s, Aquetong Spring is known to have supplied enough water to turn two grist mills regularly throughout the year, and to have concurrently powered numerous mills including a paper mill, a fulling mill, two merchant mills, four sawmills, and an oil mill.
Around 1870, the 15-acre Aquetong Lake was created by constructing a dam at the east end of the property. This provided additional power for the local mills and a recreation area for the public. A fish hatchery was constructed at the base of the spring outfall, portions of which can still be viewed today. Shad, brook trout, and terrapin turtles were raised in the hatchery, which was available for public viewing at a cost of 25 cents per person.
Then, in 1993, the Pennsylvania Fish and Boat Commission acquired the property. A few years later, with the support of Bucks County Trout Unlimited, Solebury Township began negotiating to obtain ownership of the site. Around 1996, the State performed emergency repairs on the dam; a six-foot section of the outlet structure was removed in order to take pressure off the aging barrier. This lowered the level of the lake and added about 80 feet of wetlands to the western shoreline. However, it was recognized that a complete repair of the dam could cost over $1 million and might not be the best choice for the environment.
In 2009, after almost 15 years of negotiations, Solebury Township gained control of the property, with the goal of preserving this important natural resource. It purchased the lake and surrounding properties from the state and obtained a 25-year lease. The Township’s total costs were substantially reduced because it received a large credit in exchange for its commitment to repair the dam in the future, as well as funding from the Bucks County Natural Areas Program toward the purchase.
Following the purchase, the Township engaged in a five-year process of community outreach and consultation with environmental experts in which it considered alternatives for the Aquetong Lake dam. Choices included rebuilding the dam in its then-current form, creating a smaller lake with a cold-water bypass into Aquetong Creek, or breaching the dam and restoring a free-flowing stream. Ultimately, recognizing that the lake was a thermal reservoir which introduced warm water into Aquetong Creek and eventually into the streams and river, the Township decided to breach rather than restore the dam, and return the site to its natural state.
The Aquetong Restoration Project got underway in 2015, and Solebury Township breached the historic mill dam in Aquetong Spring Park to convert the former lake into a natural area with a free-flowing, cold water stream capable of supporting native brook trout.
After the dam breach, areas of active erosion were observed along the mainstem and a major tributary of Aquetong Creek. The steep, eroding banks, increased the sediment load to the Creek's sensitive aquatic habitat.
As with most dam removal projects, a degree of stewardship is necessary to enhance the establishment of desirable, beneficial vegetation. Additionally, Solebury Township wanted to control invasive species in Aquetong Spring Park and replant the project area with native species.
The Township secured funding to construct riparian buffers, implement streambank stabilization measures, establish trout habitat structures within the mainstem and its tributary, control invasive species, and implement a woodland restoration plan. The project was funded by a $250,000 grant from the PA Department of Conservation and Natural Resources, with an equal match from the Township. Additional grants for the project were provided by the PA Department of Community and Economic Development and the National Fish and Wildlife Foundation.
Solebury Township contracted Princeton Hydro to design the stabilization of the stream channel and floodplains within the former impoundment, monitor the stream and wetlands before and after implementation, and obtain the permits for the restoration of the former impoundment. Princeton Hydro team members designed the restoration of the main channel and tributary to reduce channel and bank erosion while supporting the brook trout habitat.
After gathering and reviewing the existing data for the site, Princeton Hydro conducted field investigations to inform and guide the final design including surveying cross sections and performing fluvial geomorphological assessments of the existing channel. Pebble counts were performed, cross sections were analyzed, and existing hydrological data was reviewed to inform the design. Simultaneously, an invasive species control and woodland restoration plan was developed for the park.
Data collected from the site was used to develop a geomorphically-appropriate, dynamically-stable design. The proposed channel design included excavation of impounded sediment to create stable channel dimensions, the addition of gravel, cobble, and boulder substrate where original/existing channel substrates were absent or insufficient, and the installation of large wood features to create aquatic habitat and enhance stability of channel bed and banks.
The banks and riparian corridor were vegetated with native seed, shrubs and trees to ultimately create a wooded, shaded riparian buffer. The design ultimately stabilized the streambanks with features that double as trout habitat and replanted the surrounding park with native vegetation.
The project was replanted with an incredibly diverse set of native species that included:
In addition to restoring the stream in the former impoundment, as a part of its Strategic Master Plan for Aquetong Spring Park, Solebury Township expanded its focus of the restoration project to include another 20 acres of forested land.
For this, Solebury developed a Woodland Restoration Plan which identified over 1,000 diseased forest trees, composed mostly of ash (Fraxinus sp.) and black walnut (Juglans nigra). It was the Township’s objective to remove the hazardous trees, re-establish a native woodland community, and establish an invasive species management program.
The trees removed as a part of this effort were repurposed for the stream restoration project and used for habitat features, stream stabilization measures, and park features (i.e. benches).
Princeton Hydro also provided stormwater design support for adjacent areas in Aquetong Spring Park, including multiple stormwater connections to the main tributary. After completion, Princeton Hydro provided bid assistance, developed a probable cost, drafted technical specifications, and produced a bid package to assist Aquetong Township in bringing the project to construction.
This restoration success could not have been possible without the hard work of so many dedicated project partners: Aquetong Spring Advisory Council, Bucks County Trout Unlimited, Solebury Township, Aquetong Township, Simone Collins Landscape Architects, PA Department of Conservation and Natural Resources, PA Department of Community and Economic Development, the National Fish and Wildlife Foundation, Lenni-Lenape Turtle Clan, and Princeton Hydro.
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Princeton Hydro specializes in the planning, design, permitting, implementing, and maintenance of ecological rehabilitation projects. To learn more about our watershed restoration services, click here. To learn about some of our award-winning restoration projects check out our blogs about the Pin Oak Forest Conservation Area freshwater wetland restoration project:
On the Paulins Kill, the 100-year old Columbia Lake Dam has almost been completely removed, and fish passage has been restored! Since the first cut was executed on the main dam in August, many exciting advances have been made towards restoring the Paulins Kill back to its natural state. Check out the video below, courtesy of the New Jersey Nature Conservancy Volunteer Drone Team.
Piece by piece, the dam was notched out throughout the fall season and is now completely removed with the exception of the dam apron, the horizontal concrete structure that sits downstream of the dam, and the section of the dam that sits below the riverbed. The part of the dam in the riverbed is now being removed all the way down to three feet under the ground. The full removal is estimated to be complete by mid-March. In mid-August, the first cut was widened to 80 feet, allowing for better management of high flows during storm events, which had been posing a challenge immediately following the first cut.
In late August, the installation of rock vanes at the Brugler Road Bridge began. Rock vanes are engineered, in-stream structures that help to stabilize a channel while enhancing aquatic habitat and movement.
The rock vanes installed at the Brugler Road Bridge site are cross vanes. Cross vanes consist of a set of boulders angled upstream on a river, with another section of smaller rocks placed upstream. The taller sections of the cross vanes deflect the streamflow away from the banks, decreasing scouring effects. Instead, the flow travels over the rock walls and concentrates down the center of the channel, creating a deep and elongated pool in the middle of the stream.
Velocities between the notches in the rock vanes were evaluated using a velocity meter in accordance with the design specifications originally proposed. Based on the U.S. Fish and Wildlife Service fish passage design criteria, velocities in the notches could not be greater than 8.25 feet per second. All of the velocity measurements in this rock vane were below the maximum thresholds, ensuring no blockage of fish passage is made through the vanes.
Since the removal of the dam began, vegetative growth from the natural seedbed of the upper impoundment has been observed (see photo below).
In October, scour protection installation commenced at the Warrington Road Bridge site. After the team conducted geotechnical test pits, they discovered that a concrete scour wall that slopes out to the Paulins Kill was present and deep enough to be able to install rock at the necessary depth. They also found that the existing gabions, caged baskets filled with rock or concrete often used to protect against erosion, were intact and could be left in place. The team installed four (4) feet of riprap under and around the bridge in the riverbed and tied it into the existing grade of the banks.
The original notch in the dam was lowered one foot per day starting in mid-December, reducing water surface elevations down to the apron elevation during the month of January.
To accommodate NJ Fish and Wildlife’s request for animal passage under the I-80 bridges, an area of the previously installed riprap on the northwest abutment wall was flattened out and filled in with river cobble. This path will promote wildlife movement under the bridge as opposed to through the existing tunnel.
Currently, rock vanes are being installed under the I-80 bridges specifically to enhance fish passage. These structures vary slightly from the rock vanes at the Brugler Road Bridge site, as they are designed to slow river flow, helping migrating fish travel upstream and traverse a 5-foot elevation difference in the streambed, much like a fish ladder.
These rock vanes are more than halfway completed and are on track to be finished in time for fish populations to make full use of them. The next steps are to finish the demolition of the dam and the construction of the fish passage rock vanes under the I-80 bridges, plant vegetation throughout the upper impoundment, create a recreational trail through the upper impoundment, and plan for fishing and boating access! Stay tuned for more exciting developments on this incredible project.
Thank you to our project partners: The Nature Conservancy, American Rivers, U.S. Fish and Wildlife Service, and NJDEP Division of Fish and Wildlife Service.
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Princeton Hydro has designed, permitted, and overseen the reconstruction, repair, and removal of a dozens of small and large dams in the Northeast. To learn more about our fish passage and dam removal engineering services, visit: bit.ly/DamBarrier.
As one of the Chesapeake Bay’s most productive tributaries and a vital part of Maryland's natural resources, Mattawoman Creek supports some of the largest populations of finfish, amphibians, and birds in the state. A collaborative team of private and public sector entities have designed the "Mattawoman Creek Mitigation Site" in Pomfret, Charles County, Maryland, an effort that will enhance or create 64+ acres of wetlands and restore nearly 3,800 linear feet of this perennial stream. With over 28,500 native trees and shrubs to be planted, this mitigation project will result in 80+ acres of continuous, forested wetland with complex and diverse vegetative communities. It is expected to provide a wide array of habitat to resident and transient wildlife, including birds, reptiles, invertebrates, amphibians and rare, threatened and endangered species.
Unique to this project, Mattawoman Creek Mitigation Site is Maryland’s first-ever Umbrella Mitigation Banking Instrument (UMBI) for federal and other government agency use. A UMBI is the bundling of multiple mitigation banks into one agreement in order to streamline the regulatory approval process, thereby eliminating steps and involving fewer resources. The Maryland UMBI document helps the USAF and other public agencies secure certainty of cost and schedule, facilitate timely permit issuance, and expedite the satisfaction of their permitted requirements for planned capital improvement projects. This approach also maximizes the scale of restoration and resulting land protection and efforts, creating contiguous blocks of habitat with greatly enhanced benefits compared to single, permittee-responsible projects. This precedent was a result of a partnership between United States Air Force (USAF) and Joint Base Andrews (JBA), U.S. Army Corps of Engineers (USACE), Maryland Department of the Environment (MDE), GreenTrust Alliance, GreenVest, and Princeton Hydro.
Projects completed under the UMBI will reduce federal and state workload expediting the regulatory review and issuance of permits by the MDE and USACE. Additionally, projects completed under this UMBI will aid in compliance with the Federal Paperwork Reduction Act where federal regulatory staff can evaluate success and performance issues for multiple permittees at one single habitat restoration or mitigation site. In addition, federal costs are capped, and liabilities are transferred through to GreenVest, the private sector operator, and GreenTrust Alliance, the nonprofit bank sponsor, who will also serve as the long-term steward of sites restored under this program.
Design, engineering/modeling, and permitting of the site was completed by Princeton Hydro and GreenVest under our currently Ecosystem Restoration contract with the USACE. Princeton Hydro also provided an Environmental Assessment and Environmental Baseline Survey, and conducted a geotechnical investigation, which included the advancement of test pits, visual and manual investigation techniques and logging, infiltration testing, laboratory soils testing, and seasonal high-water table estimations.
A wetland water budget was also developed for the proposed wetland creation and restoration to determine if sufficient water is available to establish or reestablish wetlands on the site. It was also used to inform design development including proposed grading and plant community composition. The establishment and re-establishment of wetlands on the site will be accomplished through directed grading, ditch plugging and stream restoration designed to maximize the retention of surface water, floodplain re-connection, and groundwater inputs.
Over 6,000 acres (25%) of the Mattawoman Creek watershed has been protected by public ownership and various conservation and agricultural easements, which, in addition to the Mattawoman Creek Mitigation Site, help ensure that Mattawoman Creek forever remains a high-quality destination for outdoor recreation.
Princeton Hydro specializes in the planning, design, permitting, implementing, and maintenance of tidal and freshwater wetland rehabilitation projects. To learn more about our wetland restoration, creation, and enhancement services, visit: http://bit.ly/PHwetland
VIDEO: "Columbia Lake Dam when the water level was 18 inches to 2 feet lower" Video courtesy of Matt Hencheck
To read part two of our Aquatic Organism Passage blog series, click here!
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PRINCETON HYDRO
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