6 Tips To Prepare Your Pond For Spring

It’s officially time to say goodbye to winter and “spring” your pond out of hibernation mode. We’ve put together six tips for getting your pond ready for Spring and ensuring it remains healthy all year long.

1. SPRING CLEANING 

The first step in preparing your pond for Spring is to give it a thorough cleaning. Remove leaves, debris, and any surface algae that may have accumulated over the winter. For shallow ponds, you may be able to use a net or pond rake to remove debris and sediment from the bottom and along the perimeter of the pond.

2. INSPECT YOUR POND FOR DAMAGE

Inspect your pond, including berms, outlet structures, and trash racks for any damage that may have occurred over winter due to ice. If you observe any damage, we recommend contacting a professional right away. One of our engineers or certified pond managers can determine if the damage is superficial or requires more significant repairs. Also, if your pond is equipped with an aeration system, before starting it up, be sure to schedule a system inspection. A thorough inspection and proper start-up procedure will ensure the system remains fully and effectively operational for the entire summer.

3. PUT YOUR POND TO THE TEST

The routine testing of your pond’s water quality is an important part of preventing harmful algae growth, fish kills, and other problems. We recommend conducting a “Spring start up” water quality analysis of your pond. The resulting data will inform the management process and allow for the development of a pro-active, eco-friendly management plan. Maintaining your pond’s water quality helps to control nuisance aquatic species and promote environmental conditions supportive of a healthy and productive fishery.

4. AQUASCAPE YOUR SHORELINE

It’s important to check the pond’s shoreline for any signs of erosion. Mowing to the water line, especially in ponds that have fluctuating water levels, can lead to severe shoreline erosion. Eroding shorelines can be easily stabilized by planting native, riparian plants.

Deep-rooted, native emergent aquatic vegetation is able to tolerate alternating periods of exposure and dry inundation. The correct combination of native aquatic plants, emergent wetland plants, and transitional upland plants can correct or prevent chronic shoreline erosion problems. A properly planted (aquascaped) edge beautifies the shoreline, stabilizes erosion problems, creates fish and amphibian habitat, attracts pollinating species and a variety of birds, and decreases mosquito breeding.

5. CONSIDER INSTALLING AN AERATION SYSTEM

Sub-surface aeration systems eliminate stagnant water and keep your pond thoroughly mixed and properly circulated. These systems are the most cost-effective and energy-efficient way to maintain proper pond circulation. Proper aeration enhances fish habitat, minimizes the occurrence of algae blooms, and prevents mosquito breeding. It’s best to contact a certified lake/pond manager to first determine if aeration is the right solution for you. If it is, an aeration system tailored to your pond’s needs can be designed and installed.

6. HAVE AN ECOLOGICALLY BALANCED POND MANAGEMENT PLAN

There is more to pond management than weed and algae treatments alone. There is also a big difference between simple pond maintenance and ecologically-based pond management. A customized pond management plan acts as a “blueprint” that guides  proactive, long-term care for your pond.

Our certified lake and pond managers can assess the status of your pond and provide you with an environmentally holistic management plan that is based on the unique physical, hydrologic, chemical, and biological attributes of your pond. A management plan identifies the causes of your pond’s problems and provides you with the guidance needed to correct these problems. The results are far more environmentally sustainable than simple (and often unnecessary) reactive weed and algae treatments.

 

To learn more about our lake and pond management services or schedule a consultation, visit: http://bit.ly/pondlake.

Part One: Damned If You Do, Dammed If You Don’t: Making Decisions and Resolving Conflicts on Dam Removal

People have been building dams since prerecorded history for a wide variety of economically valuable purposes including water supply, flood control, and hydroelectric power. Back in the 1950s and 60s, the U.S. saw a boom in infrastructure development, and dams were being built with little regard to their impacts on rivers and the environment. By the 1970s, the rapid progression of dam building in the U.S. led researchers to start investigating the ecological impacts of dams. Results from these early studies eventually fueled the start of proactive dam removal activities throughout the U.S.

Despite the proven benefits of dam removal, conflicts are a prevalent part of any dam removal project. Dam removal, like any other social decision-making process, brings up tensions around economics and the distribution of real and perceived gains and losses. In this two part blog series, we take a look at addressing and preventing potential conflicts and the key factors involved in dam removal decision-making – to remove or not to remove.

Why We Remove Dams

The primary reasons we remove dams are safety, economics, ecology, and regulatory. There has been a growing movement to remove dams where the costs – including environmental, safety, and socio-cultural impacts – outweigh the benefits of the dam or where the dam no longer serves any useful purpose. In some cases, it’s more beneficial economically to remove a dam than to keep it, even if it still produces revenue. Sometimes the estimated cost of inspection, repair, and maintenance can significantly exceed the cost of removal, rendering generated projected revenue insignificant.

Safety reasons are also vital, especially for cases in which dams are aging, yet still holding large amounts of water or impounded sediment. As dams age and decay, they can become public safety hazards, presenting a failure risk and flooding danger. According to American Rivers, “more than 90,000 dams in the country are no longer serving the purpose that they were built to provide decades or centuries ago.” Dam removal has increasingly become the best option for property owners who can no longer afford the rising cost of maintenance and repair work required to maintain these complex structures.

The goal of removal can be multi-faceted, including saving taxpayer money; restoring flows for migrating fish, other aquatic organisms, and wildlife; reinstating the natural sediment and nutrient flow; eliminating safety risks; and restoring opportunities for riverine recreation.

Moosup River

Common Obstacles to Dam Removal

Dam removal efforts are often subjected to a number of different obstacles that can postpone or even halt the process altogether. Reasons for retaining dams often involve: aesthetics and reservoir recreation; water intakes/diversions; hydroelectric; quantity/quality of sediment; funding issues; cultural/historic values of manmade structures; owner buy-in; sensitive species; and community politics.

Of those common restoration obstacles, one of the more frequently encountered challenges is cost and funding. Determining who pays for the removal of a dam is often a complex issue. Sometimes, removal can be financed by the dam owner, local, state, and federal governments, and in some cases agreements are made whereby multiple stakeholders contribute to cover the costs. Funding for dam removal projects can be difficult to obtain because it typically has to come from a variety of sources.

Anecdotally, opposition also stems from fear of change and fear of the unknown. Bruce Babbitt, the United States Secretary of the Interior from 1993 through 2001 and dam removal advocate, said in an article he wrote, titled A River Runs Against It: America’s Evolving View of Dams, “I always wonder what is it about the sound of a sledgehammer on concrete that evokes such a reaction? We routinely demolish buildings that have served their purpose or when there is a better use for the land. Why not dams? For whatever reason, we view dams as akin to the pyramids of Egypt—a permanent part of the landscape, timeless monuments to our civilization and technology.”

Negative public perceptions of dam removal and its consequences can seriously impede removal projects. Although there are many reasons for the resistance to dam removal, it is important that each be understood and addressed in order to find solutions that fulfill both the needs of the environment and the local communities.

Stay tuned for Part Two of this blog series in which we explore strategies for analyzing dams and what goes into deciding if a dam should remain or be removed.

Study Data Leads to Healthier Wreck Pond Ecosystem

Wreck Pond is a tidal pond located on the coast of the Atlantic Ocean in southern Monmouth County, New Jersey. The 73-acre pond, which was originally connected to the sea by a small and shifting inlet, got its name in the 1800s due to the numerous shipwrecks that occurred at the mouth of the inlet. The Sea Girt Lighthouse was built to prevent such accidents. In the 1930s, the inlet was filled in and an outfall pipe was installed, thus creating Wreck Pond. The outfall pipe allowed limited tidal exchange between Wreck Pond and the Atlantic Ocean.

In the 1960s, Wreck Pond flourished with wildlife and was a popular destination for recreational activities with tourists coming to the area mainly from New York City and western New Jersey. In the early spring, hundreds of river herring would migrate into Wreck Pond, travelling up its tributaries — Wreck Pond Brook, Hurleys Pond Brook and Hannabrand Brook — to spawn. During the summer, the pond was bustling with recreational activities like swimming, fishing, and sailing.

Over time, however, the combination of restricted tidal flow and pollution, attributable to increased development of the watershed, led to a number of environmental issues within the watershed, including impaired water quality, reduced fish populations, and flooding.

Throughout the Wreck Pond watershed, high stream velocities during flood conditions have caused the destabilization and erosion of stream banks, which has resulted in the loss of riparian vegetation and filling of wetlands. Discharge from Wreck Pond during heavy rains conveys nonpoint source pollutants that negatively impact nearby Spring Lake and Sea Girt beaches resulting in beach closings due to elevated bacteria counts. Watershed erosion and sediment transported with stormwater runoff has also contributed to excessive amounts of sedimentation and accumulations of settled sediment, not only within Wreck Pond, but at the outfall pipe as well. This sediment further impeded tidal flushing and the passage of anadromous fish into and out of Wreck Pond.

In 2012, Hurricane Sandy caused wide-spread destruction throughout New Jersey and the entire eastern seaboard. The storm event also caused a major breach of the Wreck Pond watershed’s dune beach system and failure of the outfall pipe. The breach formed a natural inlet next to the outfall pipe, recreating the connection to the Atlantic Ocean that once existed. This was the first time the inlet had been open since the 1930s, and the reopening cast a new light on the benefits of additional flow between the pond and the ocean.

Hurricane Sandy sparked a renewed interest in reducing flooding impacts throughout the watershed, including efforts to restore the water quality and ecology of Wreck Pond. The breach caused by Hurricane Sandy was not stable, and the inlet began to rapidly close due to the deposition of beach sand and the discharge of sediment from Wreck Pond and its watershed.

Princeton Hydro and HDR generated the data used to support the goals of the feasibility study through a USACE-approved model of Wreck Pond that examined the dynamics of Wreck Pond along with the water bodies directly upland, the watershed, and the offshore waters in the immediate vicinity of the ocean outfall. The model was calibrated and verified using available “normalized” tide data. Neighboring Deal Lake, which is also tidally connected to the ocean by a similar outfall pipe, was used as the “reference” waterbody. The Wreck Pond System model evaluated the hydraulic characteristics of Wreck Pond with and without the modified outfall pipe, computed pollutant inputs from the surrounding watershed, and predicted Wreck Pond’s water quality and ecological response. The calibrated model was also used to investigate the effects and longevity of dredging and other waterway feature modifications.

As part of the study, Princeton Hydro and HDR completed hazardous, toxic, and radioactive waste (HTRW) and geotechnical investigations of Wreck Pond’s sediment to assess potential flood damage reduction and ecological restoration efforts of the waterbody. The investigation included the progression of 10 sediment borings conducted within the main body of Wreck Pond, as well as primary tributaries to the pond. The borings, conducted under the supervision of our geotechnical staff, were progressed through the surgical accumulated sediment, not the underlying parent material. Samples were collected for analysis by Princeton Hydro’s AMRL-accredited (AASHTO Materials Reference Library) and USACE-certified laboratory. In accordance with NJDEP requirements, sediment samples were also forwarded to a subcontracted analytical laboratory for analysis of potential nonpoint source pollutants.

In the geotechnical laboratory, the samples were subjected to geotechnical indexing tests, including grain size, organic content, moisture content, and plasticity/liquid limits. For soil strength parameters, the in-field Standard Penetration Test (SPT), as well as laboratory unconfined compression tests, were performed on a clay sample to provide parameters for slope stability modeling.

The culvert construction and sediment dredging were completed at the end of 2016. Continued restoration efforts, informed and directed by the data developed through Princeton Hydro’s feasibility study, are helping to reduce the risk of flooding to surrounding Wreck Pond communities, increase connectivity between the pond and ocean, and improve water quality. The overall result is a healthier, more diverse, and more resilient Wreck Pond ecosystem.

During the time of the progression of study by the USACE, the American Littoral Society and the towns of Spring Lake and Sea Girt were also progressing their own restoration effort and completed the implementation of an additional culvert to the Atlantic Ocean.  The American Littoral Society was able to utilize the data, analysis, and modeling results developed by the USACE to ensure the additional culvert would increase tidal flushing and look to future restoration projects within Wreck Pond.

American Littoral Society

 

To learn more about our geotechnical engineering services, click here.

Urban Wetland Restoration to Yield Flood Protection for Bloomfield Residents

As part of the Third River Floodplain Wetland Enhancement Project,
a disturbed, flood-prone industrial site will be converted into a thriving public park.

Along the Third River and Spring Brook, two freshwater tributaries of the Passaic River, a disturbed industrial site is being transformed into 4.2 acres of wetlands, restoring the natural floodplain connection, enhancing aquatic habitat, and increasing flood storage capacity for urban stormwater runoff. The groundbreaking ceremony for this important ecological restoration project for Bloomfield Township took place last month.

“The Third River Floodplain Wetland Enhancement Project is a unique, creative solution that will transform a highly-disturbed, flood-prone, former industrial site into a thriving public park allowing for both passive and active recreational activities,” said Mark Gallagher, Vice President of Princeton Hydro. “By removing a little over four acres of upland historic fill in this densely developed area and converting it to a functioning floodplain wetland, the project will restore valuable ecological functions, increase flood storage capacity, and enhance wildlife habitat.”

Princeton Hydro is serving as the ecological engineer to Bloomfield Township for the Third River Floodplain Wetland Enhancement Project. Princeton Hydro’s scientists and engineers have assisted in obtaining grants, collected background ecological data through field sampling and surveying, created a water budget, completed all necessary permitting, and designed both the conceptual and final restoration plans. Additionally, Princeton Hydro will be conducting construction oversight during the implementation of this important urban wetland creation project.

The site includes 1,360 feet along the east bank of the Third River and 3,040 feet along the banks of the Spring Brook. These waterways are freshwater tributaries of the Passaic River and share a history of flooding above the site’s 100-year flood plain. The Third River, like many urban streams, tends to be the victim of excessive volume and is subjected to erosion and chronic, uncontrolled flooding. This green infrastructure project will re-establish the natural floodplain wetland and riparian plant communities, which will lead to a species-rich forest community through the removal of invasive species, setting the stage for native plants.

“Over 500 trees and shrubs will be planted in the new wetland with additional trees and shrubs being planted along Lion Gate Drive and in existing woodlands. The selected native plant species all provide important wildlife value such as providing fruit for migratory birds,” Gallagher explained. “We are excited to work with Bloomfield Township to design an urban restoration project that will both enhance the site’s ecological and flood storage value and provide accessibility to the community of Bloomfield.”

It is estimated that Phase One of the project, which includes the wetland construction and plantings, will be completed by September 1, 2019. The maintenance building, concession stand, ball field, etc., will be constructed as part of Phase Two.

“We are very excited to break ground on this exciting project that will have tremendous public benefits, like providing much-needed open space and lowering flood insurance rates for nearby residents and businesses,” said Bloomfield Township Mayor Michael Venezia. “By taking an underutilized parcel of land and turning it into beautiful park and waterfront space to be enjoyed by the public, we are fulfilling our commitment to preserving and enhancing open space. We would not have accomplished this without the efforts of Councilman Nick Joanow, who has advocated for this park for many years, Township Administrator Matthew Watkins, our excellent contractors and environmental experts, and I would like to thank them all. I also want to thank the Department of Environmental Protection and Freshwater Wetlands Mitigation Council for their important grant assistance to help us jump start this complex which will enrich the lives of Bloomfield residents for decades to come.”

NY/NJ Baykeeper has been vital in bringing the project to fruition, having served as an advocate for the project for the last 17 years.

“Lion’s Gate natural restoration is a legitimate all-in-one project that uses green infrastructure and smart planning to address the nested set of urban land use challenges, including: stormwater management, flooding, brownfield cleanup, natural habitat restoration, and the need for both more active playing fields and more passive greenfields,” said Greg Remaud, Baykeeper and CEO, NY/NJ Baykeeper.

Together, Bloomfield Township, Strauss and Associates, ARH, and Princeton Hydro secured $1.76 million in funding for this project from the New Jersey Freshwater Wetlands Mitigation Council and another several million dollars from NJDEP’s Office of Natural Resource Restoration.

To read more about our wetland restoration work, go here: http://bit.ly/PHwetland

 

Wetland Restoration Project Wins “Land Ethics” Award of Merit

The Pin Oak Forest Conservation Area, located in a heavily developed area of northern Middlesex County, New Jersey, once suffered from wetland and stream channel degradation, habitat fragmentation, decreased biodiversity due to invasive species, and ecological impairment. The site was viewed as one of only a few large-scale freshwater wetland restoration opportunities remaining in this region of New Jersey. Thus, a dynamic partnership between government agencies, NGOs, and private industry, was formed to steward the property back to life and restore its natural function. Today, at Bowman’s Hill Wildflower Preserve’s 19th Annual Land Ethics Symposium, Middlesex County and the project team were presented with the “Land Ethics Award of Merit” for its remarkable restoration achievements.

“In just a few years, the landscape at Pin Oak has transformed from a degraded, disconnected wetland to a healthy, high-functioning landscape,” said Mark Gallagher, Vice President of Princeton Hydro. “This restoration project exemplifies how a diverse group of public and private entities can work together to identify opportunities, overcome challenges and achieve tremendous success.”

The Pin Oak restoration team includes Middlesex County Office of Parks and Recreation, Woodbridge Township, Woodbridge River Watch, New Jersey Freshwater Wetlands Mitigation Council, GreenTrust Alliance, GreenVest, and Princeton Hydro.

The Pin Oak Forest Conservation Area is a 97-acre tract of open space that contains a large wetland complex at the headwaters of Woodbridge Creek. In 2017, the award-winning restoration project converted over 30 acres of degraded freshwater wetlands, streams and disturbed uplands dominated by invasive species into a species-rich and highly functional headwater wetland complex. The resulting ecosystem provides valuable habitat for wildlife and a nurturing environment for native plants such as pin oak, swamp white oak, marsh hibiscus, and swamp rose. The restored headwater wetland system provides stormwater management, floodplain storage, enhanced groundwater recharge onsite, and surface water flows to Woodbridge Creek, as well as public hiking trails, all benefiting the town of Woodbridge.

The Land Ethics Award recognizes the creative use of native plants in the landscape, sustainable and regenerative design, and ethical land management and construction practices. The recipient is selected by a jury of professionals in the field of design, preservation and conservation, and the award is presented at the Annual Symposium.

Photo courtesy of Barbara Storms, Bowman’s Hill Wildflower Preserve.

In addition to the Award of Merit, Bowman’s Hill Wildflower Preserve’s honored Dr. Marion Kyde with the 2019 Land Ethics Director’s Award and Doylestown Township Environmental Advisory Council with the 2019 Land Ethics Award. Congratulations to all of the winners!

Established in 1934, Bowman’s Hill Wildflower Preserve is a 134-acre nature preserve, botanical garden, and accredited museum working to inspire the appreciation and use of native plants by serving as a sanctuary and educational resource for conservation and stewardship. For more information, visit www.bhwp.org.

Read more about the Pin Oak Forest Restoration project:

Innovative and Effective Approach to Wetland Restoration

To learn more about Princeton Hydro’s wetland restoration services and recent projects, visit us here: http://bit.ly/PHwetland

 

Part Two: Reducing Flood Risk in Moodna Creek Watershed

Photo of Moodna Creek taken from the Forge Hill Road bridge, New Windsor Post Hurricane Irene (Courtesy of Daniel Case via Wikimedia Commons)

This two-part blog series showcases our work in the Moodna Creek Watershed in order to explore common methodologies used to estimate flood risk, develop a flood management strategy, and reduce flooding.

Welcome to Part Two: Flood Risk Reduction and Stormwater Management in the Moodna Creek Watershed

As we laid out in Part One of this blog series, the Moodna Creek Watershed, which covers 180 square miles of eastern Orange County, New York, has seen population growth in recent years and has experienced significant flooding from extreme weather events like Hurricane Irene, Tropical Storm Lee, and Hurricane Sandy. Reports indicate that the Moodna Creek Watershed’s flood risk will likely increase as time passes.

Understanding the existing and anticipated conditions for flooding within a watershed is a critical step to reducing risk. Our analysis revealed that flood risk in the Lower Moodna is predominantly driven by high-velocity flows that cause erosion, scouring, and damage to in-stream structures. The second cause of risk is back-flooding due to naturally formed and man-made constrictions within the channel. Other factors that have influenced flood risk within the watershed, include development within the floodplain and poor stormwater management.

Now, let’s take a closer look at a few of the strategies that we recommended for the Lower Moodna Watershed to address these issues and reduce current and future flood risk:

Stormwater Management

Damage to Butternut Drive caused when Moodna Creek flooded after Hurricane Irene (Courtesy of Daniel Case via Wikimedia Commons)

Stormwater is the runoff or excess water caused by precipitation such as rainwater or snowmelt. In urban areas, it flows over sewer gates which often drain into a lake or river. In natural landscapes, plants absorb and utilize stormwater, with the excess draining into local waterways.  In developed areas, like the Moodna Creek watershed, challenges arise from high volumes of uncontrolled stormwater runoff. The result is more water in streams and rivers in a shorter amount of time, producing higher peak flows and contributing to flooding issues.

Pollutant loading is also a major issue with uncontrolled stormwater runoff. Population growth and development are major contributors to the amount of pollutants in runoff as well as the volume and rate of runoff. Together, they can cause changes in hydrology and water quality that result in habitat loss, increased flooding, decreased aquatic biological diversity, and increased sedimentation and erosion.

To reduce flood hazards within the watershed, stormwater management is a primary focus and critical first step of the Moodna Creek Watershed Management Plan. The recommended stormwater improvement strategies include:

  • Minimizing the amount of impervious area within the watershed for new development, and replacing existing impervious surfaces with planter boxes, rain gardens and porous pavement.
  • Utilizing low-impact design measures like bioretention basins and constructed-wetland systems that mimic the role of natural wetlands by temporarily detaining and filtering stormwater.
  • Ensuring the long-term protection and viability of the watershed’s natural wetlands.

The project team recommended that stormwater management be required for all projects and that building regulations ensure development does not change the quantity, quality, or timing of run-off from any parcel within the watershed. Recommendations also stressed the importance of stormwater management ordinances focusing on future flood risk as well as addressing the existing flooding issues.

Floodplain Storage

Floodplains are the low-lying areas of land where floodwater periodically spreads when a river or stream overtops its banks. The floodplain provides a valuable function by storing floodwaters, buffering the effect of peak runoff, lessening erosion, and capturing nutrient-laden sediment.

Communities, like the Moodna Creek watershed, can reduce flooding by rehabilitating water conveyance channels to slow down the flow, increasing floodplain storage in order to intercept rainwater closer to where it falls, and creating floodplain benches to store flood water conveyed in the channel.  Increasing floodplain storage can be an approach that mimics and enhances the natural functions of the system.

One of the major causes of flooding along the Lower Moodna was the channel’s inability to maintain and hold high volumes of water caused by rain events. During a significant rain event, the Lower Moodna channel tends to swell, and water spills over its banks and into the community causing flooding. One way to resolve this issue is by changing the grading and increasing the size and depth of the floodplain in certain areas to safely store and infiltrate floodwater. The project team identified several additional opportunities to increase floodplain storage throughout the watershed.

One of the primary areas of opportunity was the Storm King Golf Club project site (above). The team analyzed the topography of the golf course to see if directing flow onto the greens would alter the extent and reach of the floodplain thus reducing the potential for flooding along the roadways and properties in the adjacent neighborhoods. Based on LiDAR data, it was estimated that the alteration of 27 acres could increase floodplain storage by 130.5 acre-feet, which is equivalent to approximately 42.5 million gallons per event.

Land Preservation & Critical Environmental Area Designation

For areas where land preservation is not a financially viable option, but the land is undeveloped, prone to flooding, and offers ecological value that would be impacted by development, the project team recommended a potential Critical Environmental Area (CEA) designation. A CEA designation does not protect land in perpetuity from development, but would trigger environmental reviews for proposed development under the NY State Quality Environmental Review Act. And, the designation provides an additional layer of scrutiny on projects to ensure they will not exacerbate flooding within the watershed or result in an unintentional increase in risk to existing properties and infrastructure.

Conserved riparian areas also generate a range of ecosystem services, in addition to the hazard mitigation benefits they provide. Protected forests, wetlands, and grasslands along rivers and streams can improve water quality, provide habitat to many species, and offer a wide range of recreational opportunities. Given the co-benefits that protected lands provide, there is growing interest in floodplain conservation as a flood damage reduction strategy.


These are just a few of the flood risk reduction strategies we recommended for the Lower Moodna Creek watershed. For a more in-depth look at the proposed flood mitigation strategies and techniques, download a free copy of our Moodna Creek Watershed and Flood Mitigation Assessment presentation.

Revisit part-one of this blog series, which explores some of the concepts and methods used to estimate flood risk for existing conditions in the year 2050 and develop a flood management strategy.

Two-Part Blog Series: Flood Assessment, Mitigation & Management

For more information about Princeton Hydro’s flood management services, go here: http://bit.ly/PHfloodplain

Conservation Spotlight: Reducing Flood Risk and Restoring Wetlands in Jamaica Bay

Located in Queens, New York on the northern shore of Jamaica Bay, Spring Creek South contains approximately 237 acres of undeveloped land, including wetlands and 2.4 miles of coastline. The site is bounded by the Howard Beach residential neighborhood in Queens, a commercial area along Cross Bay Boulevard, the Belt Parkway, and Jamaica Bay. The northwest section of Spring Creek South is part of the National Park Service’s Gateway National Recreation Area, and is largely comprised of small patches of degraded tidal marsh and disturbed and degraded upland ecosystems.

On October 29, 2012, Hurricane Sandy drove a catastrophic storm surge into the New Jersey and New York coastlines. Spring Creek South and the surrounding community of Howard Beach experienced record flooding and damage to property and critical infrastructure. Storm tides caused damage and erosion along the shoreline and in the salt marsh area, degrading important habitat and leaving the site vulnerable to invasive species.

Hurricane Sandy Aftermath at Howard Beach, taken 10/30/2012 by Pam Andrade

The New York State Division of Homeland Security and Emergency Services (NYSDHSES) was awarded funding from FEMA’s Hazard Mitigation Grant Program to restore Spring Creek South. The U.S. Army Corps of Engineers (USACE) New York District, serving as project administrator, contracted Princeton Hydro to provide ecosystem restoration services. The goal of the project is to reduce future flood risk exposure while also protecting, restoring, and improving the quality and function of ecological systems; improving stormwater management and water quality; and enhancing the park’s visitor experience.

To achieve this goal, the project team is using an integrated approach that involves utilizing green infrastructure to create a natural barrier for the community and reduce the risks of coastal storms. Project activities include berm construction and the restoration of tidal marsh, creation of freshwater wetland forest, and creation of maritime shrub, forest, and grassland habitats, as well as stabilization of the existing shoreline.

On December 31, 2018, we completed Phase One of the project, which entails engineering design and preliminary permitting. More specifically, we’ve provided conceptual planning; analysis of subsurface soils for geotechnical properties and hazardous waste; coastal and freshwater wetland delineations; biological benchmarking analysis; and the development of sea level rise curves and two-dimensional hydrologic and hydraulic coastal modeling. As part of the hydrology study, we analyzed what the site could be expected to look like in 50 years due to climate changes and sea level rise. Our engineering design was also brought to 65% completion.

We also obtained permits, prepared the Environmental Assessment (EA), and oversaw the National Environmental Policy Act (NEPA) process. The EA received a “Finding of No Significant Impact” (FONSI) from FEMA, which means the environmental analysis and interagency review concluded that the project has no significant impacts on the quality of the environment.

Due to the complex nature of this project and its location, we are coordinating with a variety of different entities, including the local Howard Beach Community Board, the FAA (proximity to JFK International Airport), Port Authority, USACE, NOAA Fisheries, USFWS, USEPA, NYSDEC, NYC DEP, the National Park Service, HDR Engineering and WSP Engineering.

Phase Two of the project is the construction phase, which is expected to take about two years to complete. A key part of the Spring Creek South construction activities is the restoration of approximately 40 acres of tidal marsh, which is anticipated to improve water quality locally by stabilizing sediment, reducing erosion, and filtering dissolved particulate materials. The project team will restore existing coastline areas and install a salt marsh along the shoreline. Planted with native flora, like Spartina alterniflora, a perennial deciduous grass found in intertidal wetlands, the coastal salt marsh will help to stabilize sediment. Additionally, removing invasive species like Phragmites australis from the area and replacing it with native plant species will increase the ability for native vegetation to colonize the site, improve vegetative diversity, and reduce fire risk in the park.

A forested wetland area and berm will also be created in order to provide the surrounding communities with natural shields and buffers to future storms. The berm, with an elevation of 19 feet (NAVD88), will help to manage the risk of storm surge flooding caused by coastal storms. The forested wetland area will also provide improved stormwater runoff storage, naturally filter stormwater, and, via flap gates, direct its flow toward Jamaica Bay, away from residential and commercial properties.

These measures will help to dissipate wind and wave energy, increase shoreline resilience, improve stormwater management at the site, and create habitat that increases the ecological value and biodiversity at the site, while providing resilience benefits. Restoration activities will benefit vulnerable and rare ecological communities by producing localized environmental enhancements, including improving water quality and creating and restoring habitat. The project also increases opportunities for recreational uses such as wildlife viewing/photography, fishing, and nature study.

Princeton Hydro specializes in the planning, design, permitting, implementing, and maintenance of wetland rehabilitation projects. To learn more about some of our ecosystem restoration and enhancement services, visit: bit.ly/PHwetland.

 

Employee Spotlight: Meet Our New Team Members

We’re excited to welcome four new members to our team. The addition of this group of talented individuals strengthens our commitment to delivering great service that exceeds our clients’ expectations.

Meet Our New Team Members
Miranda Lepek, EIT, Water Resource Engineer

Miranda is a civil engineer with expertise in grading and stormwater design, CAD drafting, environmental sampling, and construction oversight. Prior to Princeton Hydro, she worked for a small site development firm in Michigan where she developed her drafting skills and facilitated multiple aspects of private and commercial land development projects.

Miranda holds a B.S. in Civil Engineering from the University of Michigan – Ann Arbor. While on study abroad, she contributed to the one of the longest-running native amphibian field studies in New Zealand. In other previous experiences, she worked on major projects including the investigation phases of a Superfund site cleanup in Duluth, MN and a comprehensive sampling operation over 40 miles of the Hudson River near Albany, NY. In her free time, Miranda enjoys hiking, foraging, cooking and art.

Sumantha Prasad, PE, ENV SP, Water Resource Engineer

Sumantha is a Water Resource Engineer with a B.S. in Bioenvironmental Engineering from Rutgers University and a M.S. in Environmental Engineering and Science from Johns Hopkins University. She worked in Maryland for seven years focusing on ecological restoration projects, including stream restoration, wetland creation and enhancement, and stormwater management, and she worked for 3 years with a primary focus on highway hydrology and hydraulics.

In her spare time, she enjoys being a Toastmaster and serves as the Treasurer to a 501(c)3 organization dedicated to creating inclusive housing communities for adults with disabilities. She also enjoys telling terrible puns unapologetically.

Pat Rose, Environmental Scientist

Pat’s interest in aquatics began during a summer course studying at Lake Atitlán, Guatemala as an undergraduate at SUNY Oneonta. After graduation, he spent a year volunteering with AmeriCorps in Knoxville, Tennessee as part of a Water Quality Team. While in Tennessee, Pat spent the majority of his time educating high school students on how to protect and improve local waterways and watersheds as part of the Adopt-A-Watershed program. During his year with AmeriCorps, Pat worked with government organizations to perform biological sampling and erosion monitoring in local streams.

Pat graduated from SUNY Oneonta with a M.S. in Lake Management in December 2018. During his time in graduate school, he created an interim lake management plan for a small reservoir in New York that has had cyanobacterial blooms over the past few years. Pat spent this past summer completing a co-op with an aquatic plant management company in the Pacific Northwest, working primarily with invasive Eurasian and hybrid watermilfoil populations.

Duncan Simpson, Senior Environmental Scientist

For nearly a decade, Duncan has served as an Environmental Scientist/Planner in the Mid-Atlantic Region. His experience includes a wide range of natural resource studies, documentation, and permitting at both the project and program level. He has special expertise in wetlands; Waters of the US delineations; and permitting for stormwater management facilities, stream restoration, and TMDL program projects. He has conducted forest stand delineations; rare, threatened and endangered species consultations; mitigation monitoring; and National Environmental Policy Act (NEPA) documentation.

Duncan holds an M.S in Biology from Towson University and a B.S. in Environmental Science with a Wildlife and Fisheries Conservation Minor from the University of Massachusetts. During his graduate studies, he researched amphibian species found in Delmarva Bays and testing models that predict their presence based on abiotic habitat characteristics. He also served as a student member of the Northeast Partners in Amphibian and Reptile Conservation (NEPARC) steering committee. Duncan is a Professional Wetland Scientist and member of the Society of Wetland Scientists. In his spare time, he enjoys hiking with his dog and learning how to fly fish.

 

Understanding and Implementing Green Infrastructure

By Tucker Simmons and Dr. Clay Emerson, PE, CFM

People generally think of green infrastructure as an eco-friendly way to handle stormwater runoff. While many green infrastructure elements are planned and managed specifically for stormwater control, the capabilities and benefits are far reaching. In this piece, we’ll provide an in-depth look at all that green infrastructure encompasses, best practices, and real-world examples of green infrastructure projects in action.

WHAT IS GREEN INFRASTRUCTURE?

Defined as an approach to water management that protects, restores, or mimics the natural water cycle, green infrastructure can be implemented for large scale projects and small scale projects alike.

Unlike conventional, or “gray” infrastructure, green infrastructure uses vegetation, soil, and other natural components to manage stormwater and generate healthier urban environments. Green infrastructure systems mimic natural hydrology to take advantage of interception, evapotranspiration and infiltration of stormwater runoff at its source. Examples include permeable pavers, rain gardens, bioretention basins, rain barrels, and tree boxes.

WHY IS GREEN INFRASTRUCTURE BENEFICIAL?

Green infrastructure provides various benefits, including cleaning and conserving water, reducing flooding, improving public health, providing jobs, beautifying neighborhoods, supporting wildlife and providing economic benefits at both the larger community and individual household level. Let’s take a closer look at some of the primary benefits:

Prevents Flooding: By absorbing and slowing the flow of water, green infrastructure can reduce the burden on storm sewer systems and mitigate localized flooding.

Saves Money: While some green infrastructure designs may require the same or greater initial investment than conventional strategies, green design methods provide a big return in reducing costs over the long-term.

Improves Water Quality: Through natural absorption and filtration processes, green infrastructure significantly reduces stormwater runoff volume, decreases the pollutants and particulates within the stormwater, and improves the quality of the runoff flowing into surrounding water bodies.

Improves Air Quality: Green infrastructure techniques like tree boxes, green roofs and vegetative barriers have long been associated with improving air quality. Urban tree boxes help shade surfaces, effectively putting moisture into the air while reducing greenhouse gases. Trees mitigate heat and air pollution, both cooling and cleaning the air.

Enhances Aesthetics: Many green infrastructure practices utilize native plants and trees to improve runoff absorption and reduce stormwater pollution. This vegetation can provide a sound barrier or privacy screen for properties, and enhances the overall aesthetics of the surrounding environment. 

Increases Property Values: Research shows that property values increase when trees and other vegetation are present in urban areas. Planting trees can increase property values by as much as 15%.

LARGE-SCALE GREEN INFRASTRUCTURE IMPLEMENTATION:

With the use of proper design techniques, green infrastructure can be applied almost anywhere and is especially beneficial in urban areas. In developed environments, unmanaged stormwater creates two major issues: one related to the volume and timing of stormwater runoff (flooding) and the other related to pollutants the water carries. Green Infrastructure in urban environments can recharge groundwater, decrease runoff, improve water quality, and restore aquatic habitats while controlling flooding.

Across the United States, more than 700 cities utilize combined sewer systems (CSS) to collect and convey both sanitary sewage and stormwater to wastewater treatment facilities. During dry weather, all wastewater flows are conveyed to a sewage treatment plant where it receives appropriate treatment before it is discharged to the waterway. However, during heavy rainfall or significant snowmelt, the additional flow exceeds the capacity of the system resulting in a discharge of untreated sewage and stormwater to the waterway; this discharge is referred to as a combined sewer overflow (CSOs). For many cities with CSS, CSOs remain one of the greatest challenges to meeting water quality standards. Green infrastructure practices mimic natural hydrologic processes to reduce the quantity and/or rate of stormwater flows into the CSS.

New Jersey, as part of the 2012 USEPA’s Integrated Municipal Stormwater and Wastewater Planning Approach Framework, utilized green infrastructure as one of the main components in managing its CSS and reducing CSOs. Because of the flexibility of green infrastructure in design performance, it can reduce and mitigate localized flooding and sewer back-ups while also reducing CSOs. An integrated plan that addresses both overflows and flooding can often be more cost-effective than addressing these issues separately. New Jersey, in addition to meeting its CSO reduction goals, is using green infrastructure throughout the sewershed to build resilience to large storm events and improve stormwater management.

Stormwater planters installed by the Philadelphia Water Department

Philadelphia takes advantage of numerous green stormwater infrastructure programs such as Green Streets, Green Schools, and Green Parking. There are a wide variety of green infrastructure practices that Philadelphia is using to decrease stormwater runoff throughout the entire city. After just five years of implementing the Green City, Green Waterplan, Philadelphia has reduced the stormwater pollution entering its waterways by 85%. Using over 1,100 green stormwater tools (i.e. CSO, living landscapes, permeable surfaces, etc.), in just one year, Philadelphia was able to prevent over 1.7 billion gallons of polluted water from entering their rivers and streams.

New York City is using a green infrastructure program, led by its Department of Environmental Protection, that utilizes multiple green infrastructure practices to promote the natural movement of water while preventing polluted stormwater runoff from entering sewer systems and surrounding waterbodies. While attaining this goal, the green infrastructure also provides improvements in water and air quality, as well as improves the aesthetics of the streets and neighborhoods. According to the NYC Green Infrastructure Plan, “By 2030, we estimate that New Yorkers will receive between $139 million and $418 million in additional benefits such as reduced energy bills, increased property values, and improved health.”

SMALL-SCALE GREEN INFRASTRUCTURE IMPLEMENTATION:

Green infrastructure techniques are extremely beneficial on every scale. Residential homes and neighborhoods can benefit from the implementation of green infrastructure in more ways than many people realize. There are a wide variety of green infrastructure projects that can be completed with a relatively small time and financial investment. Many of us at Princeton Hydro have incorporated green infrastructure practices into our homes and properties. Here’s a look at some of those projects in action:

Dr. Steve Souza, a founding principal of Princeton Hydro, installed rain gardens throughout his property utilizing native, drought-resistant, pollinator-attracting plants. The rain gardens are designed to capture and infiltrate rainwater runoff from the roof, driveway, patio and lawn.

Princeton Hydro’s President Geoffrey Goll, P.E. built an infiltration trench in his backyard. An infiltration trench is a type of best management practice (BMP) that is used to manage stormwater runoff, prevent flooding and downstream erosion, and improve water quality in adjacent waterways. 

And, in the front yard, Geoffrey installed a variety of wildflower plantings.

MUNICIPAL TOOLKIT

An interactive website toolkit was recently launched by New Jersey Future to help municipalities across the state incorporate green infrastructure projects into their communities. For this project, Princeton Hydro’s engineers and scientists provided real-world examples integrating green infrastructure into development in order to bring to light the benefits and importance of investing in green infrastructure at the local level. The New Jersey Green Infrastructure Municipal Toolkit provides expert information on planning, implementing, and sustaining green infrastructure to manage stormwater. This toolkit acts as a one-stop resource for community leaders who want to sustainably manage stormwater, reduce localized flooding, and improve water quality.

GET STARTED

Since its inception, Princeton Hydro has been a leader in innovative, cost-effective, and environmentally sound stormwater management systems. Long before the term “green infrastructure” was part of the design community’s lexicon, the firm’s engineers were integrating stormwater management with natural systems to fulfill such diverse objectives as flood control, water quality protection, and pollutant reduction. Princeton Hydro has developed regional nonpoint source pollutant budgets for over 100 waterways. The preparation of stormwater management plans and design of stormwater management systems for pollutant reduction is an integral part of many of the firm’s projects.

Interested in working with us on your next Green Infrastructure project? Contact us here.


Tucker Simmons, Water Resources Intern

Tucker is a Civil and Environmental Engineering major at Rowan University focusing on Water Resources Engineering. He is the President and player of the Rowan University Men’s DII Ice Hockey Team. His Junior Clinic experience includes the study of Bio-Cemented sand and the Remote Sensing of Landfill Fires. In the future, Tucker hopes to work on creating a more sustainable environment. Tucker enjoys playing ice hockey, being with friends and family, and exercising.

 

Clay Emerson, Senior Project Manager

Clay’s areas of expertise include hydrologic and hydraulic analysis, stormwater management and infiltration, nonpoint source (NPS) pollution, watershed modeling, groundwater hydrology/modeling, and water quality and quantity monitoring at both the individual site and watershed scales. His educational and work experience includes a substantial amount of crossover between engineering and environmental science applications. He has specific expertise in the field of stormwater infiltration and has conducted extensive research on the NPS pollution control and water quantity control performance of stormwater BMPs. He regularly disseminates his monitoring results through numerous peer-reviewed journal publications, magazine articles, and presentations.

 

Two-Part Blog Series: Flood Assessment, Mitigation & Management

In this two part blog series, we showcase our work in the Moodna Creek Watershed in order to explore some of the concepts and methods used to estimate flood risk for existing conditions and the year 2050 and develop a flood management strategy (Part One), and traditional engineering and natural systems solutions used to manage and reduce flood risk (Part Two).

Part One: Flood Assessment & Mitigation Analysis in the Moodna Creek Watershed

The greater Moodna Creek watershed covers 180 square miles of eastern Orange County, NY. The watershed includes 22 municipalities and hundreds of streams before joining the Hudson River. This region has seen tremendous growth in recent years with the expansion of regional transit networks and critical infrastructure.

The Moodna Creek watershed can be split into two sub-basins — the Upper Moodna Creek and the Lower Moodna Creek. In the span of 15 months, Hurricane Irene, Tropical Storm Lee, and Hurricane Sandy each have caused significant flooding throughout the Moodna Creek watershed, damaging public facilities, roadways, and private properties. Both sub-basin communities have noted a concern about increased flood risk as more development occurs.

As global temperatures rise, climate models are predicting more intense rainfall events. And, the flood risk for communities along waterways — like the Moodna Creek watershed — will likely increase as time passes. In order to understand existing and future risk from flood events in this flood-prone area, a flood risk management strategy needed to be developed. The strategy uses a cost-benefit analysis to review the feasibility of each measure and the overall impact in reducing flood risks.

With funds provided from a 2016 grant program sponsored by the New England Interstate Waters Pollution Control Commission (NEIWPCC) and the New York State Department of Environmental Conservation’s (NYCDEC) Hudson River Estuary Program (HEP), Princeton Hydro along with a variety of project partners completed a flood assessment and flood mitigation analysis specific to the Lower Moodna Creek watershed.

Let’s take a closer look at our work with the Lower Moodna Creek watershed, and explore some of the methods used to estimate flood risk and develop a flood management strategy:

Lower Moodna Creek Watershed Flood Assessment & Analysis

The primary Lower Moodna Creek project goals were to assess flood vulnerabilities and propose flood mitigation solutions that consider both traditional engineering strategies and natural systems solution approaches (land preservation, wetland/forest restoration, green infrastructure and green water management). The project team focused on ways to use the natural environment to reduce risk.  Instead of strictly focusing on just Moonda Creek, the team took a holistic approach which included all areas that drain into the river too. These analyses were incorporated into a Flood Assessment Master Plan and Flood Mitigation Plan, which will serve as a road map to reducing flooding issues within the watershed.

Managing Flood Risk

The first step in managing flood risk is to understand what type of exposure the communities face. The Moodna Creek project modeled flooding within the watershed during normal rain events, extreme rain events, and future rain events with two primary goals in mind:

Visual assessment being conducted in flood-prone areas of Moodna Creek Watershed.

  • Assess the facilities, infrastructure, and urban development that are at risk from flooding along the Moodna Creek and its tributaries within the study area.
  • Develop a series of hydrologic and hydraulic models to assess the extent of potential flooding from the 10-year (10%), 100-year (1%),  and 500-year (0.2%) storm recurrence intervals within the study area. The modeling includes flows for these storm events under existing conditions and also hypothetical scenarios with predicted increases in precipitation and population growth.

 

The project team used these models and data to propose and evaluate a series of design measures that help reduce and mitigate existing and anticipated flood risk within the study area. Where possible, the proposed solutions prioritized approaches that protect and/or mirror natural flood protection mechanisms within the watershed such as floodplain re-connection and wetland establishment. In addition to flood protection, the project components also provide water quality protection, aesthetics and recreation, pollutant reduction, and wildlife habitat creation.

Land Use and Zoning

Zoning is a powerful tool that determines a region’s exposure to hazards and risk. Zoning determines which uses are permitted, or encouraged, to be built in moderate and high-risk areas. It also prevents certain uses, such as critical facilities, from being built in those areas. Zoning is also a determinant of a region’s character and identity.

In the Lower Moodna Creek watershed, a large majority (82%) of land is zoned for residential use. However, in the flood-prone areas, there is a higher ratio of areas zoned for non-residential uses (commercial, industrial) than in areas that are zoned for potential future development. Specifically, within the 10-year storm recurrence floodplain, 30% of the land is zoned for industrial use. This is likely because several facilities, such as wastewater treatment plants and mills, require access to the river and were strategically developed to be within immediate proximity of waterfront access. The Lower Moodna zoning analysis demonstrated a general preference within watershed to limit residential use of flood-prone areas. 

Land Preservation

Preserving land allows for natural stormwater management, as well as limits the exposure of development, and minimizes sources of erosion within the watershed. Preserved land also maintains the hydrologic and ecologic function of the land by allowing rainwater to be absorbed or retained where it falls and thus minimizing run-off. If the land within the floodplain is preserved, it will never be developed, and therefore the risk — a calculation of rate exposure and the value of the potential damage — is eliminated.  Therefore, land preservation, both within the floodplains and in upland areas, is the best way to minimize flood damage.

Conserved riparian areas also generate a range of ecosystem services, in addition to the hazard mitigation benefits they provide. Protected forests, grasslands, and wetlands along rivers and streams can improve water quality, provide habitat to many species, and offer a wide range of recreational opportunities. Given the co-benefits that protected lands provide, there is growing interest in floodplain conservation as a flood damage reduction strategy.

Within the mapped Lower Moodna floodplains, our assessment determined that there appears to be a slight priority for preserving land most at-risk for flooding. This is likely a consequence of prioritizing land that is closest to riparian areas and preserving wetland areas, which are the most likely to experience flooding. Within the floodplains for the 10-year storm, approximately 22.7% is preserved. For the 100-year storm, approximately 21.2% of the land is preserved. Within the 500-year storm, this number drops slightly to 20.3%. These numbers are so close in part because the difference between the 10-year, 100-year, and 500-year floodplains are small in many areas of the watershed.

Hydrology and Hydraulics

Hydrology is the scientific study of the waters of the earth, with a particular focus on how rainfall and evaporation affect the flow of water in streams and storm drains. Hydraulics is the engineering analysis of the flow of water in channels, pipelines, and other hydraulic structures. Hydrology and hydraulics analyses are a key part of flood management.

As part of this flood assessment, Princeton Hydro created a series of hydrologic and hydraulic (H&H) models to assess the extent of potential flooding from the 10-year, 100-year, and 500-year storm recurrence intervals within the Lower Moodna. The modeling, which included flows for these storm events under existing conditions and future conditions based on predicted increases in precipitation and population growth, makes it easier to assess what new areas are most impacted in the future.

These are just a few of the assessments we conducted to analyze the ways in which flooding within the watershed may be affected by changes in land use, precipitation, and mitigation efforts. The flood models we developed informed our recommendations and proposed flood mitigation solutions for reducing and mitigating existing and anticipated flood risk.

Check out Part Two of this blog series in which we explore flood risk-reduction strategies that include both traditional engineering and natural systems solutions:

Part Two: Reducing Flood Risk in Moodna Creek Watershed

For more information about Princeton Hydro’s flood management services, go here: http://bit.ly/PHfloodplain.