Princeton Hydro Opens a New Office

We are pleased to announce the opening of our new Mid-Atlantic office located in Millersville, Maryland, allowing us to better serve existing and future clients throughout Maryland and Delaware. With the addition of this new location, Princeton Hydro now has five full-service offices from Maryland to Connecticut

For the past nine years Princeton Hydro, LLC has provided pond and lake management services to clients throughout Maryland and Delaware. We are now pleased to announce the official opening of our Mid-Atlantic office, located in Millersville, MD. From this strategic location we will be able to provide both existing and future clients in the Maryland and Delaware region with a full suite of services including but not limited to:

Over the past 20 years Princeton Hydro has become the recognized industry leader in the management and restoration of lakes and ponds. Our certified lake and pond managers are backed by a dedicated staff of water resource engineers, wetland scientists and fishery biologists who have the expertise and experience to solve even the most difficult lake and pond problems.

To commemorate the opening of our Maryland office, Princeton Hydro is extending discounted prices to new and existing clients in Maryland and Delaware for 2017 lake and pond management services. If you would like to schedule a no-cost, no-obligation site consultation, please contact Scott Churm, Director of Aquatic Operations, at schurm@princetonhydro.com.

We appreciate your business!

 

The Plight of Aging Dams, and One Solution

As dams age, the danger to life and property around them increases. If they were to suddenly fail and flood downstream communities and infrastructure, there would be serious loss of property and life. More and more, dam removal has become the best option for property owners who no longer want or can no longer afford the rising cost of maintenance and repair work required to maintain such a complex structure.

The Courier-Post recently published this Commentary piece titled, “The Plight of Aging Dams, and One Solution”, which was written by Princeton Hydro’s Vice President and Principal Engineer Geoffrey M. Goll:

Many of our nation’s dams, while originally intended to provide benefits for mills, water supply and energy generation, are severely aged and unmaintained. Nearly 20,000 of the dams on the Army Corps of Engineers’ National Inventory of Dams – which doesn’t even include many dams that are not inventoried or known about – were built in the 1960s. With expected lifespans of 50 years, these dams have reached their limit. And by 2020, 70 percent of all dams will be over 50 years old. Like roads and bridges, dams also require upkeep, maintenance and eventually removal or rehabilitation.

As dams age, the danger to life and property around them increases. If they were to suddenly fail and flood downstream communities and infrastructure, there would be loss of property and life. The Association of State Dam Safety Officials, the professional organization for dam safety engineering professionals and regulators, estimates there would need to be a $21 billion investment to repair just 2,000 deficient, high-hazard dams. More and more, the removal of dams has become an option for owners who no longer want or no longer can afford the rising cost of maintenance and repair work required to maintain such a complex structure.

For dams like this, removal benefits local economies, and eliminates threats to people and property in local communities. There are also many byproduct benefits, including restoring fish migration routes, improving water quality, restoring floodplain functions and values, and increasing biodiversity.

On Sept. 8, we had the honor of meeting the Secretary of the Interior Sally Jewell during a visit of our Hughesville Dam removal project on the Musconetcong River, located in northwestern New Jersey. This project exemplifies the successes that can be achieved through public-private partnerships, including local communities, state and federal agencies, nongovernmental organizations, and private commercial entities. This is the fifth dam removed on the Musconetcong River by a coalition of stakeholders, led by the Musconetcong Watershed Association. The Department of the Interior (specifically, the U.S. Fish and Wildlife Service) provided funding to remove this very old, out-of-compliance dam.

The success of these partnerships is due to the unique strengths that each organization brings to the table. This project achieved the removal of a flood and safety hazard, and will restore additional river miles for migratory fish, improve water quality by removing the heat sink of the reservoir, and provide additional safe passage for recreation along the river.

It is easy to see why Secretary Jewell chose this site to visit, but the old and outdated dam at Hughesville is far from alone. Across the nation, we need to remove dams like this at a much larger scale – aging dams that no longer are of value to us, but increase the danger to those who live downstream. If we can build on this momentum and start to address the issue of dam safety compliance on a national scale, we can address these threats to American’s safety and strengthen local economies.

Client Spotlight: Roaring Brook Lake, Putnam Valley, NY

A Comprehensive Lake Management Plan Designed by Princeton Hydro

roaring-brook-lake Since 1998, Princeton Hydro has been working with the Town of Putnam Valley, often referred to as the Town of Lakes, to restore and maintain its waterbodies. The most recent area of focus is Roaring Brook Lake, a 115-acre man-made lake surrounded by a wooded landscape community that includes 260+ homes. The lake provides a variety of recreational opportunities for boaters, anglers, swimmers and outdoor lovers and is the center point of the Roaring Brook Lake District.

The Town of Putnam Valley and the Roaring Brook Lake District hired Princeton Hydro to conduct a thorough analysis of the lake’s ecological health, identify problems affecting the quality of the lake, and develop a detailed plan to improve and protect the lake. Specifically, Princeton Hydro will implement a detailed assessment of the lake that involves water quality monitoring, bathymetric mapping (measurement of lake depth and sediment thickness), aquatic plant surveys, and quantification of the lake’s hydrologic and pollutant budgets. These data will be utilized collectively to produce a comprehensive management plan for Roaring Brook Lake and its watershed.

Water Quality Monitoring

Water quality data are used to interpret the existing chemistry of the lake, identify water quality trends, pinpoint problems and assess nutrient levels.

At Roaring Brook Lake, Princeton Hydro will specifically collect in-situ data from the surface to the bottom of the water column. The resulting temperature, dissolved oxygen, pH and conductivity data will be used in combination with laboratory generated data to assess the lake’s thermal stability and investigate the potential for internal phosphorus loading. In addition, samples will be collected to identify phytoplankton and zooplankton in the lake; some of the plankton is considered a nuisance while others are considered valuable relative to the lake’s food web.

Bathymetric Assessment

The bathymetric assessment will generate accurate lake water depth, and provide sediment thickness and distribution data for the entire body of water. These data are then used to evaluate the need for dredging, asses how and where aquatic plants become colonized and other management options that can affect long-term decisions regarding the restoration and protection of Roaring Brook Lake. The bathymetric data are also used in the various trophic models that help predict the lake’s response to incoming nutrients.

Specifically, Princeton Hydro will utilize hydrographic surveying methods to conduct the bathymetric assessment of Roaring Brook Lake. A specialized dual frequency fathometer will be used to measure water depth and the thickness of the unconsolidated sediment present throughout the lake. The fathometer is directly tied into GPS, so data are consistently collected at the exact position of the survey transects. The GPS data and accompanying water depth data will be placed into a GIS format for the generation of morphometric data and bathymetric maps of the lake.

Aquatic Plant Mapping

Aquatic plants hold sediments in place, reduce erosion and provide habitat for fish and other important wildlife and insects. Although native aquatic plants are imperative to a lake’s health, an overabundance of these plants and the presence of invasive plants can have very negative impacts.

Princeton Hydro will be conducting a complete mapping of the aquatic plant community within Roaring Brook Lake to identify the plant species present in the lake, their relative abundance and location, and provide a basis for future evaluation of changes in the plant community. This data will greatly inform lake management activities moving forward. Additionally, with this data, Princeton Hydro will be able to assess the effectiveness of the resident grass carp – currently stocked in the lake – in keeping the submerged vegetation under control.

 

Hydrologic and Pollutant Budget

The hydrologic budget represents the water balance of a lake, accounting on an annual scale for all of the inputs and losses of water. The hydrologic data is used extensively in conducting trophic state analyses and is important in determining the feasibility and utility of many in-lake restoration techniques. At Roaring Brook Lake, Princeton Hydro will investigate and quantify four key components of the hydrologic budget, including direct precipitation, overland runoff (stormwater, snowmelt, etc.), tributary inflow and groundwater seepage.

Once the hydrologic budget is complete and land-use has been categorized and quantified, a pollutant budget can then be developed. The development of a detailed pollutant budget is a critical component of any lake management plan. For the purpose of the Roaring Brook Lake study, the term pollutant refers to the nutrients nitrogen and phosphorus as well as total suspended solids. The pollutant budget represents a quantification of the input of pollutants from various sources to the lake. Because the amount of nitrogen and phosphorus present in the lake stimulates eutrophication and results in water quality impacts, proper quantification of the nutrient load is critical for the development of a site-specific and cost effective management plan.

Data Analysis

The data analysis for Roaring Brook Lake will focus on identifying an acceptable in-lake condition (i.e. specific level of algal biomass in the lake) and correlate this to the lake’s annual phosphorus load through a robust water quality model.

The data analysis will involve the review of both historical and current data and will be used to identify correlations and relationships between existing pollutant concentrations/loads and unacceptable water quality conditions (i.e. algal blooms, high rates of turbidity, nuisance densities of aquatic plants, etc.). Water quality thresholds and goals will be established for assessing the long-term progress of the lake management plan.

Lake Management Plan

roaring-brook-lake-1Properly managing your lakes and ponds starts with developing a customized management plan and involves a holistic approach to ensure continued success.

A good management plan is informed by substantial data collection and analysis (as described above); includes any necessary permit requirements and a proposed timetable for implementation; provides recommendations for priority ranking of particular activities and restoration measures; and discusses predicted benefits of the plan’s implementation and how each activity is linked to the established water quality goals. A well-crafted and thorough lake management plan will also include a review of the various Federal, State, County and local grants, programs and initiatives that may provide funding for the identified in-lake and watershed projects.

• • •

Princeton Hydro’s work with Roaring Brook Lake marks the 16th project they’ve conducted for the Town of Putnam Valley. Princeton Hydro’s proven success in watershed management stems from the cumulative training and experience of its staff, and its ability to develop watershed management solutions that are both practical and effective, which has led to the firm’s very high success rate in improving water quality.

If you’re interested in developing a customized, comprehensive management plan for your lake or pond, please contact us!

 

 

 

 

The Westtown Dam and Lake Restoration Project is Now Complete!

westtown-0720161456Princeton Hydro is proud to announce the completion of the Westtown dam restoration and dredging project. For the past 10 years, Princeton Hydro has been working with the Westtown School on dam safety compliance and lake restoration and is the engineer-of-record for the restoration of the Westtown dam and lake.

Westtown School, a hallmark of the Westtown Lake community, initially contracted Princeton Hydro to complete dam inspections and assess the lake in terms of its environmental health and the need for dredging. The completion of this project is a testament to the School’s commitment to its mission of “inspiring and preparing its graduates to be stewards and leaders of a better world”. The School leads by example through practicing dam safety compliance and working to restore the lake for future generations.

westtown-img_2438For the dam, Princeton Hydro completed periodic visual inspections, dam breach and inundation analysis, the preparation of an Emergency Action Plan (EAP), and the Operations and Maintenance Manual.

For rehabilitation, Princeton Hydro designed the dam to be able to pass the 100-year flood event via a completely new drop spillway and outfall barrel, and the construction of an auxiliary/emergency cast-in-place stepped spillway. As part of the rehabilitation of the dam, Princeton Hydro surveyed and designed the dredging of 56,000 cubic yards of sediment, the rehabilitation of the lake’s sedimentation forebay and spillway, and the enlargement of a culvert on Westtown Road, immediately downstream of the dam. The culvert replacement was required due to the closure of two secondary outlets on the dam and corresponding culverts below Westtown Road.

westtown-0713161041aThis project also required a variety of permits, including a Chester County soil erosion and sediment control plan approval, a Dam Safety construction permit, a PADEP General Permit 11 for the road crossing, and a US Army Corps of Engineers Individual Permit in compliance with the Federal Clean Water Act.

Additionally, Princeton Hydro successfully navigated interests for two species of concern: the bog turtle (federal and state listed) habitat and red-bellied turtle (state listed) populations.

Following design and permitting, Princeton Hydro provided construction documentation and administration, including the review of shop drawings, monitoring soil compaction, inspecting concrete pours and collecting concrete test cylinders for break tests (ACI certified engineers), completing monthly progress reports, reviewing payment requests and change orders, and attend bi-weekly project meetings with the client. Flyway Excavating, the contractor for the project, worked seamlessly with the School and Princeton Hydro to accomplish the overall goals of the design.

The Westtown project is an excellent example of Princeton Hydro’s turnkey engineering, permitting, and construction administration services. Please contact us if you have a similar project you need assistance with or have questions about.

westtown-p1260748

*Photos courtesy of Flyway Excavating.

 

 

 

Truxor DM 5045 – The Newest Addition to the Princeton Hydro Family

Truxor DM5045 Stock Image We’re thrilled to announce the arrival of our new Truxor DM 5045!

This multi-functional, eco-friendly, amphibious machine effectively controls invasive weeds and problematic algae growth without the use of pesticides.

Its light-weight construction and highly advanced weight distribution system provide low ground pressure and high floating capacity. This allows the Truxor to operate on water, in deep or very shallow depths, and on dry land without disrupting sensitive environments, like nature preserves, wetlands, canal banks, golf courses and areas that are difficult to access with conventional equipment. And, the Truxor’s highly maneuverable and precise control system ensures easy passage through narrow channels and around hazards.

Equipped with a wide range of tools and accessories, the Truxor DM 5045 can perform a variety of functions, including weed cutting and harvesting, mat algae and debris removal, silt pumping, dredging, channel excavation, oil spill clean-up and much more!

This is the second Truxor to be welcomed to the Princeton Hydro family, which also includes a Marsh Master, another versatile, fully amphibious vehicle. Watch our Truxor DM 5000 in action.

If you’re interested in learning more about our innovative lake and pond management techniques or wondering if the Truxor is the right tool for one of your projects, please contact us!