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To prevent harmful algal blooms (HABs) in New Jersey’s largest lake, a clay-based nutrient inactivating technology called Phoslock, is being applied in Lake Hopatcong this week. This is the largest Phoslock treatment to occur in the Northeastern U.S. The Phoslock treatment, which is happening in the southern end of the lake called Landing Channel, is expected to take approximately one week depending on the weather conditions.

[embed]https://youtu.be/BU_lub2UR20[/embed]

Over the course of the 2019 summer season, Lake Hopatcong suffered from large-scale and persistent HABs causing local and county health agencies to close off all beaches and issue advisories over large sections of the lake. These unprecedented conditions had significant negative impacts on the ecological, recreational, and economic resources of the lake and region. In order to combat HABs in this upcoming 2020 summer season, the Lake Hopatcong Commission has partnered with the Lake Hopatcong Foundation, four municipalities (Jefferson, Hopatcong, Mt. Arlington, and Roxbury), two counties (Morris and Sussex), and their environmental consultant, Princeton Hydro, to develop both short- and long-term lake management strategies.

“The negative effects of HABs in our lake last year were numerous, widespread, and in some cases devastating,” recalled Donna Macalle-Holly of Lake Hopatcong Foundation. “It is imperative for every stakeholder to pool our resources to keep it from happening again. Collaboration is the only way to protect public health, as well as the health of New Jersey’s largest lake.”

In an effort to evaluate a variety of innovative in-lake and watershed-based measures to prevent, mitigate, and/or control harmful algal blooms in Lake Hopatcong, the Lake Hopatcong Commission was awarded a $500k grant as part of New Jersey Department of Environmental Protection’s (NJDEP) new $13.5M initiative to reduce and prevent future harmful algal blooms in New Jersey. In addition to the $500k grant, the aforementioned local government and nonprofit stakeholders provided $330k in matching funds to implement and evaluate a variety of ways to address HABs in Lake Hopatcong.

“Our lake community cannot sustain another year like 2019,” said Lake Hopatcong Commission Chairman Ron Smith. “Since the news of our grant award in early March, we have been working with our partners to make sure the projects are implemented in time for the 2020 season.”

This week, the water resource engineering and natural resource management firm, Princeton Hydro—a lake management consultant to Lake Hopatcong for over two decades—is implementing the first and largest innovative measure as part of the NJDEP HABs grant-funded project. This involves treating 50 acres of the southern end of the lake with Phoslock, a clay-based product that inactivates phosphorus in both the water column and the sediments, making this critical nutrient unavailable for algal growth. The Phoslock treatment, which requires proper permitting by NJDEP, is applied as a slurry and will be distributed from a boat. The slurry will temporarily make the water appear turbid, but should disperse approximately two to six hours after each treatment.

“We are expecting the Phoslock treatment to limit the growth of algae and therefore reduce the occurrence of harmful algal blooms in the lake this summer, keeping it open for recreation and business,” said Dr. Fred Lubnow, Director of Aquatic Resources at Princeton Hydro and leading HABs expert. “If this technology is deemed successful and cost-effective in Lake Hopatcong, we could set the precedent for large-scale HABs prevention in other lakes throughout New Jersey, and even across the nation.”

Developed by the Australian national science agency CSIRO, Phoslock is frequently used to strip the water column of dissolved phosphorus, as well as to inactivate phosphorus generated from deep, anoxic sediments. Recently, at a smaller scale, it has been shown to inactivate the mobilization of phosphorus from shallow sediments where there is a mobilization of phosphorus from both chemical and biological processes.

Algae uses phosphate, the biologically available form of phosphorus, as a food source to grow. When there is an excessive amount of phosphorus in a lake, algal growth can be dense and can negatively affect water quality. This excessive plant growth, caused by eutrophication, can both cause a lack of oxygen available, leading to fish kills, as well as produce harmful algal blooms with cyanotoxins, which are harmful to humans and pets.

[caption id="attachment_5095" align="aligncenter" width="550"] Photo credit: SePRO Corporation[/caption]

After Phoslock is applied, it sinks through the water column, binding phosphate as it moves towards the sediment. Once settled at the bottom of the lake, it forms a very thin layer and continues to bind phosphate released from the sediment, thus controlling the release of phosphorus into the lake. One pound of phosphorus has the potential to generate up to 1,100 lbs of wet algae biomass. However, 1.1 tons of Phoslock is capable of removing 24 pounds of phosphorus -- that’s over 26,000 lbs of wet algae biomass not growing in the lake for every 1.1 ton of Phoslock applied. In turn, Phoslock’s ability to suspend biologically available phosphorus is therefore a major step towards improving a lake’s water quality.

As part of the NJDEP HABs grant funding, the stakeholder group will be evaluating the relative effectiveness of this treatment strategy. Because of its shallow depth and separation from the main lake, the Landing Channel area was a good candidate for evaluation of this technology. Princeton Hydro will conduct pre- and post-treatment monitoring of the Phoslock treatment area in order to conduct an objective evaluation of the cost effectiveness of the treatment as a means of preventing the development and/or mitigation of HABs. If the study indicates that Phoslock is a cost-effective treatment, the Lake Hopatcong Commission may consider additional trials in other sections of the lake, if funding is available.

To learn more about HABs, check out our recent blog: [post_title] => Mitigating Harmful Algal Blooms at Lake Hopatcong: Largest Application of Phoslock in Northeast [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => lake-hopatcong-phoslock-treatment [to_ping] => [pinged] => [post_modified] => 2026-03-03 14:59:42 [post_modified_gmt] => 2026-03-03 14:59:42 [post_content_filtered] => [post_parent] => 0 [guid] => https://www.princetonhydro.com/blog/?p=5088 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 4 [filter] => raw ) [1] => WP_Post Object ( [ID] => 4361 [post_author] => 3 [post_date] => 2019-11-18 15:07:38 [post_date_gmt] => 2019-11-18 15:07:38 [post_content] =>

Harmful Algae Blooms (HABs) were in the spotlight this summer due to the severe impacts they had on lakes throughout the country. The nation-wide HABs outbreak caused beach closures, restricted access to lake usage, and wide-ranging health advisories.

What exactly are HABs? Why were they so severe this summer? Will this trend continue? Can anything be done to prevent the occurrence or mitigate the impacts?

In this blog, we provide answers to all of those questions, exploring what HABs are, why they occur, why they were particularly prevalent this summer, and what we can do to combat them.

[caption id="attachment_1736" align="alignnone" width="1246"]Harmful Algae Bloom Visible in Owasco Lake. Photo by: Tim Schneider Harmful Algae Bloom Visible in Owasco Lake. Photo by: Tim Schneider[/caption]

What are HABs?

Simply put, HABs are rapid, large overgrowths of cyanobacteria. Cyanobacteria, also known as blue-green algae, aren’t actually algae, they are prokaryotes, single-celled aquatic organisms that are closely related to bacteria and can photosynthesize like algae. These microorganisms are a natural part of aquatic ecosystems, but, under the right conditions (primarily heavy rains, followed by hot, sunny days), these organisms can rapidly increase to form cyanobacteria blooms, also known as HABs.

HABs can cause significant water quality issues in lakes and ponds, often forming a visible and sometimes odorous scum on the surface of the water. They can produce toxins that are incredibly harmful (even deadly) to humans, animals, and aquatic organisms.

HABs also negatively impact economic health, especially for communities dependent on the income of jobs and tourism generated through their local lakes and waterways.


What Causes HABs?

HABs are caused by a complex set of conditions, and many questions remain about exactly why they occur and how to predict their timing, duration, and toxicity. Primarily, HABs are caused by warmer temperatures and stormwater run-off pollutants, including fertilizers with phosphates.

NY Times article, featuring Princeton Hydro, looks at how climate change affects lakes nationwide, using NJ as an example. Photo by: Rick Loomis, NY Times.HABs are induced by an overabundance of nutrients in the water. The two most common nutrients are fixed nitrogen (nitrates and ammonia) and phosphorus. Discharges from wastewater treatment plants, runoff from agricultural operations, excessive fertilizer use in urban/suburban areas, and stormwater runoff can carry nitrogen and phosphorus into waterways and promote the growth of cyanobacteria.

Climate change is also a factor in HAB outbreaks, which typically occur when there are heavy rains followed by high temperatures and sunshine. Climate change is leading to more frequent, more intense rainstorms that drive run-off pollutants into waterways, coupled with more hot days to warm the water. These are the ideal conditions for HABs, which in recent years have appeared in more places, earlier in the summer.

With climate change and increasing nutrient pollution causing HABs to occur more often and in locations not previously affected, it's important for us to learn as much as we can about HABs so that we can reduce their harmful effects.


How to Prevent HABs?

Signs on the closed beach at Hopatcong State Park warn residents of the Harmful Algae Bloom at Lake Hopatcong on July 2019, in Landing, NJ. (Photo by: Danielle Parhizkaran of NorthJersey.comThe number one thing individuals can do to protect their waterbodies and prevent HABs is to reduce phosphorous use and reduce nutrient loads to waters.

According to Dr. Fred Lubnow of Princeton Hydro, “Managing loads of phosphorous in watersheds is even more important as the East Coast becomes increasingly warmer and wetter thanks to climate change. Climate change will likely need to be dealt with on a national and international scale. But local communities, groups, and individuals can have a real impact in reducing phosphorous levels in local waters.”

Here are a few steps you can take to improve water quality in your community lakes:

Controlling stormwater runoff is another critical factor in improving water quality and reducing HABs. There are a number of low-cost green infrastructure techniques that can be implemented on an individual and community-wide scale. Click here to read more about green infrastructure stormwater management techniques.

In a recent Op/Ed published on NJ.com, Princeton Hydro President Geoffrey M. Goll, P.E. lists four things that residents, businesses, and local governments should do to prevent another HABs outbreak next summer:

  1. Improve aging “gray” infrastructure
  2. Invest in “green” stormwater infrastructure
  3. Implement regional/watershed-based planning
  4. Pass the Water Quality Protection and Jobs Creation Act

"By making the necessary investments, we can simultaneously create jobs, reduce flood impacts, improve fisheries, maintain or increase lakefront property values, improve water quality and preserve our water-based tourism. The time to act is literally now," said Geoff. Go here, to read the full article.


HABs Management in Action through Floating Wetland Islands

Nitrogen and phosphorus are utilized by plants, which means they uptake these nutrients to sustain growth. We see this naturally occurring in wetland ecosystems where wetlands act as a natural water filtration system and can actually thrive from nutrients flowing in from external sources.

This process is replicated in floating wetland islands (FWIs), where you typically have a constructed floating mat with vegetation planted directly into the material. The plants then grow on the island, rooting through the floating mat.

[caption id="attachment_4363" align="aligncenter" width="554"]This illustration, created by Staff Scientist Ivy Babson, conveys the functionality of a Floating Wetland Island This illustration, created by Staff Scientist Ivy Babson, conveys the functionality of a Floating Wetland Island[/caption]  

Not only do FWIs assimilate and remove excess nitrogen and phosphorus out of the water, they also provide habitat for fish and other aquatic organisms; help mitigate wave and wind erosion impacts; provide an aesthetic element; and can be part of a holistic lake/pond management strategy. Because of this, FWIs are being utilized to improve water quality and control HABs in lakes and ponds throughout the country.

[gallery link="none" size="medium" ids="17718,17310,10666"]

Princeton Hydro has designed and implemented numerous FWIs in waterbodies large and small. Go here to learn how they’re being used in Harveys Lake.


Recognizing and monitoring the changes that are taking place in our local waterways brings the problems of climate change, stormwater pollution and the resulting water quality issues closer to home, which can help raise awareness, inspire environmentally-minded action and promote positive, noticeable change.

If you spot what you believe to be HABs in your community lake, contact your local lake association right away. They, along with their lake management team, can assess the situation and determine what further actions need to be taken. For more information about HABs, click here.

Special thanks to Princeton Hydro Staff Scientist Ivy Babson for her contributions to this blog.

[post_title] => Identifying, Understanding and Addressing Harmful Algae Blooms [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => harmful-algae-blooms [to_ping] => [pinged] => [post_modified] => 2025-11-04 02:33:38 [post_modified_gmt] => 2025-11-04 02:33:38 [post_content_filtered] => [post_parent] => 0 [guid] => https://www.princetonhydro.com/blog/?p=4361 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [2] => WP_Post Object ( [ID] => 5838 [post_author] => 3 [post_date] => 2019-08-08 16:13:09 [post_date_gmt] => 2019-08-08 16:13:09 [post_content] =>

Measuring 630+ acres, Harveys Lake, located in Luzerne County, Pennsylvania, just northeast of Wilkes-Barre, is the largest natural lake (by volume) within the Commonwealth of Pennsylvania, and is one of the most heavily used lakes in the area. It is classified as a high quality - cold water fishery habitat (HQ-CWF) and is designated for protection under the classification.

Since 2002, The Borough of Harveys Lake and the Harveys Lake Environmental Advisory Council  has worked with Princeton Hydro on a variety of lake management efforts focused around maintaining high water quality conditions, strengthening stream banks and shorelines, and managing stormwater runoff.

Successful, sustainable lake management requires identifying and correcting the cause of eutrophication as opposed to simply reacting to the symptoms of eutrophication (algae and weed growth). As such, we collect and analyze data to identify the problem sources and use these scientific findings to develop a customized management plan that includes a combination of biological, mechanical, and source control solutions. Here are some examples of the lake management strategies we've utilized for Harveys Lake:

 
Floating Wetland Islands

Floating Wetland Islands (FWIs) are an effective alternative to large, watershed-based natural wetlands. Often described as self-sustaining, FWIs provide numerous ecological benefits. They assimilate and remove excess nutrients, like nitrate and phosphorous, that could fuel algae growth; provide habitat for fish and other aquatic organisms; help mitigate wave and wind erosion impacts; and provide an aesthetic element. FWIs are also highly adaptable and can be sized, configured, and planted to fit the needs of nearly any lake, pond, or reservoir.

Five floating wetland islands were installed in Harveys Lake to assimilate and reduce nutrients already in the lake. The islands were placed in areas with high concentrations of nutrients, placed 50 feet from the shoreline and tethered in place with steel cables and anchored. A 250-square-foot FWI is estimated to remove up to 10 pounds of nutrients per year, which is significant when it comes to algae.

Princeton Hydro worked with the Harveys Lake Environmental Advisory Council and the Borough of Harveys Lake to obtain funding for the FWIs through the Pennsylvania Department of Environmental Protection (PADEP).

 
Streambank & Shoreline Stabilization

The shoreline habitat of Harveys Lake is minimal and unusual in that a paved road encompasses the lake along the shore with most of the homes and cottages located across the roadway, opposite the lake. In addition to the lake being located in a highly populated area, the limited shoreline area adds to the challenges created by urban stormwater runoff.

Runoff from urban lands and erosion of streambanks and shorelines delivers nutrients and sediment to Harveys Lake. High nutrient levels in the lake contribute to algal blooms and other water quality issues. In order to address these challenges, the project team implemented a number of small-scale streambank and inlet stabilization projects with big impacts.

The work included the stabilization of the streambank downstream for Harveys Lake dam and along Harveys Creek, the design and installation of a riparian buffer immediately along the lake’s shoreline, and selective dredging to remove sediment build up in critical areas throughout the watershed.

 
Invasive Species Management

Hydrilla (Hydrilla verticillata), an aggressively growing aquatic plant, took root in the lake in 2014 and quickly infected 250 acres of the lake in a matter of three years. If left untreated, hydrilla will grow to the water’s surface and create a thick green mat, which prevents sunlight from reaching native plants, fish and other organisms below. The lack of sunlight chokes out all aquatic life.

In order to prevent hydrilla from spreading any further, Princeton Hydro and SePRO conducted an emergency treatment of the impacted area utilizing the systemic herbicide Sonar® (Fluridone), a clay-based herbicide. SonarOne, manufactured by SePRO, blocks hydrilla’s ability to produce chloroplasts, which in turn halts the photosynthetic process. The low-concentration herbicide does not harm fish, wildlife or people using the lake. Surveys conducted after the treatment showed it was working – the hydrilla had turned white and was dying off. Additional Sonar treatments followed and efforts to eradicate hydrilla in the lake continue.

Dr. Fred Lubnow, our Director of Aquatic Programs, estimates complete eradication of the aquatic plant could take around five years. Everyone can do their part in preventing the spread of this and other invasive species. Boaters and lake users must be vigilant and remove all vegetation from the bottom of watercrafts and trailers.

 
Stormwater Best Management Practices (BMPs)

In 2009, Princeton Hydro developed a stormwater implementation plan (SIP) for Harveys Lake. The goal of the stormwater/watershed-based efforts was to reduce the lake’s existing annual total phosphorus load to be in full compliance with the established Total Maximum Daily Load (TMDL). This TMDL is related to watershed-based pollutant loads from total phosphorus (TP) and total suspended solids (TSS), which can contribute to algal blooms.

A number of structural urban runoff projects were implemented throughout the watershed. This includes the design and construction of two natural stream channel projects restoring 500 linear feet of tributaries and reducing the sediment and nutrient loads entering the lake. A series of 38 urban runoff BMPs, including nutrient separating devices and roadside infiltration, were installed in areas immediately adjacent to the lake to further reduce the loads of nutrients and other pollutants reaching the lake.

The photos below show a stormwater project that was completed in the Hemlock Gardens Section of the Watershed. Hemlock Gardens is a 28-acre section of land located in the southeastern portion of the watershed. It contains approximately 26 homes, has very steep slopes, unpaved dirt roads, and previously had no stormwater infrastructure in place.

Two structural stormwater BMPs were installed:

  • A nutrient separating baffle box, which utilizes a three-chamber basin with screens to collect leaf litter, grass clippings and trash
  • A water polishing unit that provides a platform for secondary runoff treatment

In 1994, Harveys Lake was identified as “impaired” by PADEP due to large algal blooms. In 2014, Harveys Lake was removed from the list of impaired waters. Project partners attribute the recovery of this lake to the stream restoration, urban runoff BMP implementation, and the use of in-lake nutrient reduction strategies.

The Harveys Lake Watershed Protection Plan Implementation Project proved that despite the lake being located in an urbanized watershed, it is possible to implement cost-effective green infrastructure and stormwater retrofit solutions capable of significantly decreasing pollutant loading to the lake.

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

[post_title] => Managing Urban Stormwater Runoff and Revitalizing Natural Habitat at Harveys Lake [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => urban-stormwater-runoff-harveys-lake [to_ping] => [pinged] => [post_modified] => 2025-11-04 02:24:07 [post_modified_gmt] => 2025-11-04 02:24:07 [post_content_filtered] => [post_parent] => 0 [guid] => https://www.princetonhydro.com/blog/?p=4037 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [3] => WP_Post Object ( [ID] => 3823 [post_author] => 3 [post_date] => 2019-06-20 14:47:40 [post_date_gmt] => 2019-06-20 14:47:40 [post_content] =>

The summer is upon us and Lakes Appreciation Month is right around the corner, what better time to pay a visit to and learn more about the lakes in your area.

Princeton Hydro conducts work on lakes throughout the Northeast to preserve, protect and improve water quality and ecological health, ensuring that your community lakes can be enjoyed now and into the future. Today, we’re putting the spotlight on Greenwood Lake:

Greenwood Lake, a 7-mile-long interstate lake that straddles the border of New York and New Jersey, is a popular recreation spot for residents and tourists of both states. Considered to be one of the top bass fishing lakes in New Jersey, Greenwood Lake is abundant with largemouth and smallmouth bass, yellow perch, chain pickerel and catfish. The lake is also extensively used by residents for swimming and boating.

For over 35 years, Princeton Hydro’s scientists have worked with New Jersey, local governing municipalities, and the various environmental organizations involved with the protection of Greenwood Lake and its watershed. In the early 2000s, we developed a comprehensive Restoration Plan and a proactive monitoring program that we have used over the years to properly manage the lake and its watershed. The plan was developed for the Greenwood Lake Commission and the Township of West Milford with funding provided through the New Jersey Department of Environmental Protection’s Nonpoint Source 319(h) Program. The Restoration Plan focuses heavily on the implementation of various types of stormwater best management practices (BMPs) to help reduce the influx of sediment and nutrients into the lake. We track the positive effects and benefits achieved through these stormwater projects by conducting both storm-event based and in-lake water quality monitoring.

The goal of the stormwater-based efforts is to ensure the lake’s total phosphorus (TP) load is systematically reduced in accordance with the lake’s established Total Maximum Daily Load (TMDL). The TMDL is a regulatory term in the U.S. Clean Water Act, that identifies the maximum amount of a pollutant (in this case phosphorus) that a waterbody can receive while still meeting water quality standards. Princeton Hydro was instrumental in developing the TMDL for Greenwood Lake. Phosphorus entering the lake from runoff is the primary driver of the lake’s eutrophication. The direct results of eutrophication are increases in the density of aquatic plants and nuisance algae. All this added productivity leads to reduced clarity, reductions in dissolved oxygen concentrations, and a number of other ecological impacts that compromise the quality, aesthetics, and use of the lake.

Last year, Princeton Hydro and the Greenwood Lake Commission, with input from the West Milford Environmental Commission, proposed an updated Watershed Implementation Plan (WIP) for the lake. Approved and funded by the NJ Highlands Council, the updated WIP includes a variety of components that build upon the original Restoration Plan and incorporate newly advanced stormwater management and Nonpoint Source Pollution (NPS) reduction technologies.

 

The WIP includes in?lake and stream monitoring; the assessment of the existing stormwater structures installed through grant?based, watershed activities; and the identification of watershed-based projects that can be completed to support the Lake’s compliance with TMDL TP levels with a specific focus on the stormwater runoff produced by Belcher's Creek, a major tributary to Greenwood Lake.

The WIP also includes the following nine minimum elements considered necessary by both NJDEP and USEPA for funding eligibility:

  1. Identify causes and sources of pollution
  2. Estimate pollutant loading into the watershed and the expected load reductions
  3. Describe management measures that will achieve load reductions and targeted critical areas
  4. Estimate amounts of technical and financial assistance and the relevant authoritiesBelcher's Creek at Edgecumb and Glencross needed to implement the plan
  5. Develop an information/education component
  6. Develop a project schedule
  7. Describe the interim, measurable milestones
  8. Identify indicators to measure progress
  9. Develop a monitoring component

While many of these elements have been indirectly addressed to varying degrees in the original Restoration Plan, in order to maximize Greenwood Lake’s opportunities to obtain State and Federal funding for the design and implementation of watershed control measures, the WIP now explicitly correlates the nine elements to eight specific deliverables, which are as follows:

  1. Conduct a detailed in?lake and watershed?based water quality monitoring program and compare the data to that collected in 2004 and 2005 to document changes or shifts in water quality.
  2. Meet with the Township of West Milford, Passaic County and other stakeholders to inventory recently completed BMPs and other watershed management measures.
  3. Conduct a field?based evaluation of the stormwater project completed since the original 319?grant funded Restoration Plan.
  4. Conduct site assessments to identify other potential stormwater/watershed BMP projects.
  5. Conduct a field assessment of the Belchers Creek Corridor to identify potential Nonpoint Source Pollution Reduction Projects.
  6. Assemble the WIP with all the 9 elements fully satisfied.
  7. Schedule and implement stakeholder and public meetings to evaluate project status.
  8. Submit of final version of WIP to the NJDEP and present the findings and recommendations to the public.

This project was initiated in September 2018 and is projected for completion by September 2019. The Greenwood Lake Commission, serves as the inter?State steward of the Greenwood Lake watershed, and is working closely with Princeton Hydro and the watershed stakeholders (Township of West Milford, Passaic County and others), to ensure the WIP is a holistic document.

Stay tuned for more Greenwood Lake updates as the WIP progresses. For more information about Princeton Hydro’s lake management projects and capabilities, or to discuss your project needs and goals, please contact us.

Some of the photos utilized in this blog are from The Village of Greenwood Lake.

[post_title] => Protecting Greenwood Lake's Water Quality Through Stormwater Management [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => greenwood-lake [to_ping] => [pinged] => [post_modified] => 2025-02-10 19:12:38 [post_modified_gmt] => 2025-02-10 19:12:38 [post_content_filtered] => [post_parent] => 0 [guid] => https://www.princetonhydro.com/blog/?p=3823 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [4] => WP_Post Object ( [ID] => 5803 [post_author] => 3 [post_date] => 2018-06-07 20:14:14 [post_date_gmt] => 2018-06-07 20:14:14 [post_content] =>

The Lake Hopatcong Foundation (LHF) recently launched its newest initiative - a floating classroom. The custom-built 40-foot education vessel, named 'Study Hull', gives students an interactive, hands-on education experience to explore Lake Hopatcong, learn about freshwater ecology, and learn how to protect the watershed.

During its maiden voyage field trip, which was held on May 21, fourth-graders from Nixon Elementary and Kennedy Elementary schools utilized the boat’s laboratory instruments to study water hydrology, temperatures, plankton, and dissolved oxygen levels. They performed a series of tests and experiments designed to help them learn about the general health of the lake. They used Secchi Disks to determine the depth to which light is able to penetrate the water's surface. They also learned about runoff and nonpoint source pollutants, how to protect the lake’s water quality, and how to be good stewards of the water.

Princeton Hydro helped the LHF design a teaching curriculum on water quality.  Dr. Jack Szczepanski, Senior Aquatics Scientist, and Christopher L. Mikolajczyk, CLM, Senior Project Scientist, trained the staff and volunteers on the curriculum and demonstrated various water quality monitoring techniques that can be conducted with the students.

“We’re really proud to be a part of this exciting initiative,” said Mikolajczyk. “It’s really important to get kids interested in science at an early age and teach them about their surrounding environment – where their drinking water comes from, how it gets polluted, the impacts pollution has on the lake’s ecosystem, and what steps can be made to protect the lake’s water quality. We're hoping the floating classroom field trip program will make a lasting, valuable impression with these kids.”

[gallery ids="2042,2045,2041"]

In the first year of operation it is expected that the Study Hull will host 1,000 fourth grade students. The long-term goal is to develop lesson plans for students in every grade from kindergarten through high school. Starting in July, the LHF is also offering the public tours of the floating classroom on Mondays at Hopatcong State Park.

The purchase of the floating classroom was made possible by financial support from USATODAY Network’s “A Community Thrives” program, which awarded the LHF with a $50,000 grant. The program recognizes three categories: arts and culture, education, and wellness. In each category, the first place winner received a $100,000 grant and the second and third place winners received $50,000 grants. The James P. Verhalen Family Foundation and the Szigethy Family also provided significant donations to help bring the floating classroom to life.

The LHF and Princeton Hydro are longtime partners. Starting back in 1983, Princeton Hydro’s Dr. Stephen Souza conducted the USEPA funded Diagnostic Feasibility study of the lake and then authored the Lake Hopatcong Restoration Plan. That document continues to be the backbone of why and how to restore the lake, manage the watershed, reduce pollutant loading, and address invasive aquatic plants and nuisance algae blooms.

Lake Hopatcong has one of the longest, continuous, long-term ecological databases in New Jersey; almost 30 years of consistently collected water quality data. The data is crucial in assessing the overall ecological health of the lake and proactively guiding its management, identifying and addressing emerging threats, documenting project success (a mandatory element of funding initiatives) and confirming compliance with New Jersey State Water Quality standards.

Princeton Hydro’s most recent work for Lake Hopatcong includes the implementation of green infrastructure stormwater management measures, installation of floating wetland islands to improve water quality, and invasive aquatic plant species management programs, community educational training, and surveys.

For more information about the Lake Hopatcong Foundation or the floating classroom, click here. For more information about Princeton Hydro’s lake management services, go here.

[post_title] => “Floating Classroom” Launches into Lake Hopatcong [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => lake-hopatcong-floating-classroom [to_ping] => [pinged] => [post_modified] => 2025-11-04 02:14:01 [post_modified_gmt] => 2025-11-04 02:14:01 [post_content_filtered] => [post_parent] => 0 [guid] => http://www.princetonhydro.com/blog/?p=2040 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [5] => WP_Post Object ( [ID] => 1698 [post_author] => 3 [post_date] => 2018-04-11 00:35:55 [post_date_gmt] => 2018-04-11 00:35:55 [post_content] => Throughout April and May, Princeton Hydro is participating in a variety of events focused on conserving, restoring, and protecting our precious water resources.
April 11: New Jersey Invasive Species Strike Team 10th Annual Conference
Presented by the Friends of Hopewell Valley Open Space, the 10th Annual New Jersey Invasive Species Strike Team Conference is considered the most comprehensive state-wide forum on invasive species. The conference brings participants together to collaborate and address new and emerging invasive species issues from a state-wide perspective, and includes an exhibitor hall, networking opportunities and a variety of presentations and panel discussions on topics ranging from “Rare Bird Conservation” to “Foraging for Invasive Species” to “Herbicide Application Techniques.” Princeton Hydro, a proud sponsor of the conference, will be exhibiting. We hope to see you there! View the full conference schedule.  
April 14: Musconetcong River Watershed Cleanup
As part of the 26th Annual Musconetcong River Cleanup on April 14th from 9 AM - 12 PM, Princeton Hydro will be leading a volunteer team at the Warren Glen Dam site. Friends and family welcome to join us! For details, visit the Musconetcong Watershed Association's event page.  
April 18: The New England Chapter of the American Public Works Association Spring Conference
The New England Chapter of the American Public Works Association (NEAPWA) serves professionals in all aspects of public works and supports the people, agencies, and organizations that plan, build, maintain, and improve communities. This year’s NEAPWA Spring Conference is being held at the Pratt & Whitney Stadium in East Hartford, CT. The conference includes a tour of the stadium, an exhibitor hall, educational session, and technical workshops on topics, like “Water System Infrastructure Planning in Response to Drought Conditions,” “Leveraging GIS Technology with Municipal LED Street Lights,” and “Using Infiltration and Inflow to Work Smarter not Harder.” View the full conference agenda.  
April 26: Arbor Day Planting and Bird Walk at Exton Park
We're celebrating Arbor Day on April 26th (one day early) with Friends of Exton Park. First, we'll be on the lookout for spring migrants during a morning bird walk (8:30 AM - 10:30 AM). Then, we'll show our Arbor Day spirit by planting a variety of native plants at Exton Park (11:00 AM). We hope you'll join us! Click here to RSVP.    
May 4: New York State Federation of Lake Associations Annual Conference
The New York State Federation of Lake Associations will host its 35th Annual Conference at the Fort William Henry Conference Center in Lake George, NY.  This year’s conference, which is titled, “Protecting Our Lakes for 35 Years – Our Past, Present and Future,” will feature a diverse exhibitor hall, networking opportunities, a silent auction and a variety of educational sessions. Princeton Hydro is exhibiting and giving five presentations:
  • Nutrient Inactivation: A Pennsylvania Case Study
  • You Have Your Lake Data, Now What? Creating a Watershed Plan
  • One Watershed, Many Lakes: A Strategic Plan for the Kettle Lakes of Southern Onondaga and Northern Cortland Counties
  • Proactive Management of Harmful Algal Blooms
  • Hydrilla Control in Harveys Lake, PA
Read more.

[post_title] => UPCOMING EVENTS: SPRING UPDATE FROM PRINCETON HYDRO [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => spring-2018-events [to_ping] => [pinged] => [post_modified] => 2025-10-16 20:09:59 [post_modified_gmt] => 2025-10-16 20:09:59 [post_content_filtered] => [post_parent] => 0 [guid] => http://www.princetonhydro.com/blog/?p=1698 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [6] => WP_Post Object ( [ID] => 1539 [post_author] => 3 [post_date] => 2018-03-01 10:22:52 [post_date_gmt] => 2018-03-01 10:22:52 [post_content] => Princeton Hydro is proud to participate in a number of exciting conferences throughout March. The conferences, which take place in Pennsylvania, New Jersey and Virginia, cover a wide variety of topics centered around protecting water resources. Let's dive in:
March 2: New Jersey Conservation Rally
The 22nd Annual NJ Land Conservation Rally is a one-day educational conference about preserving open space and farmland in New Jersey. The event consists of training workshops, roundtable discussions, a keynote speech from David Case, author of “Nature of Americans,” exhibitors, and a farmers market.
Princeton Hydro, a proud sponsor of the rally, is giving two presentations:
  • “Recognizing The Power of Dam Removal To Reconnect & Restore Our Ecosystem” The Nature Conservancy ’s River Restoration Manager Beth Styler Barry and Princeton Hydro'sDirector of Engineering Services Mary Paist-Goldman , P.E. will present the most effective ways to approach a comprehensive, all-inclusive dam removal in New Jersey, with particular emphasis on the Musconetcong Watershed.
  • “Nonprofit Social Media Hacks” Rally Planning Committee member Lindsay McNamara and Communication Strategist for Princeton Hydro Dana Patterson present ways to punch up your social media presence. The course is designed for social media beginners and experts alike, and will cover cross-channel techniques to help increase engagement, event attendance, and social buzz around your organization.

March 4 - 6: Virginia Water Conference
Held by the Virginia Lakes and Watershed Associationand the Virginia Floodplain Management Association, the Virginia Water Conference will host 400 participants, and will include exhibits and breakout sessions on topics ranging from floodplain management to dam safety to water resource engineering. Princeton Hydro’s Dr. Fred Lubnow, Director of Aquatic Programs, and Michael Hartshorne, Senior Limnologist, are conducting a Water Quality and Quantity breakout session titled,  "A Limnological Assessment of a 250-Acre Impoundment in Virginia for the Consideration of Nutrient Inactivation."
March 7 - 8: PA Lake Management Society Conference
The Pennsylvania Lake Management Society is hosting its 28th annual conference during which lake professionals, students, recreation enthusiasts, lakeside residents and community members will come together to explore a variety of topics related to managing lakes and reservoirs. Visit the Princeton Hydro booth to discuss the latest advancements in pond, lake and watershed management. The conference offers a collection of professional presentations, workshops and panel discussions. Princeton Hydro is giving two presentations during the conference:
  • "Continued Management of Hydrilla in Harveys Lake, Luzerne County, Pennsylvania" Lead by Michael Hartshorne, Senior Limnologist, and Scott Churm, Associate: Director of Aquatic Operations
  • “Conducting a Nutrient Inactivation Treatment for Internal Phosphorus Load Control for a Small Glacial Lake in Northern Pennsylvania” Lead by Dr. Fred Lubnow, Director of Aquatics Programs

March 10: Schuylkill Watershed Congress
The Watershed Congress is an annual event that seeks to advance the best available information and techniques for protecting and restoring watersheds by combining science, policy, and practical applications into one program. The one-day conference offers a keynote discussion on Landscape-Scale Forest Loss in the Delaware Basin, 21 concurrent sessions covering a broad range of watershed topics, poster sessions and exhibits. Dr. Fred Lubnow's breakout session, titled "Ecology/Management of Cyanotoxin Producing Blue-Green Algae in the Schuylkill River," reviews the basic ecology of nuisance blue-green algae and how to monitor, manage and prevent cyanotoxins particularly in potable water supplies.
March 15: Land Ethics Symposium
The theme for this year's 18th Annual Land Ethics Symposium, which is presented by Bowman's Hill Wildflower Preserve, is "Creative Approaches for Ecological Landscaping." The conference will focus on ways to create low-maintenance, economical and ecologically balanced landscapes using native plants and restoration techniques. Participants can take part in presentations, for which continuing education credits are available, on topics, including Installation and Management of Stormwater Basins, Landscaping for Carbon Storage and Resilience, and Watershed Restoration. The conference also offers a variety of networking events and an exhibitor hall. Princeton Hydro, a "Friends Sponsor" of the event, will have an exhibitor table. We hope to see you there!
March 19: SAME Philadelphia Post Small Business Conference
The Philadelphia Post is hosting its 12th Annual Small Business Conference and Industry Day, which aims to promote engagement between agency, industry, and small businesses. The program consists of networking events, small business exhibits, a variety of speakers and much more. The Society of American Military Engineers (SAME) gives leaders from the A/E/C, environmental, and facility management industries the opportunity to come together with federal agencies in order to showcase best practices and highlight future opportunities for small businesses to work in the federal market. If you're in attendance, please stop by the Princeton Hydro booth.

Stay tuned for more events.

[post_title] => This Month's Events: March Update from Princeton Hydro [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => march-2018-events [to_ping] => [pinged] => [post_modified] => 2024-12-10 13:39:36 [post_modified_gmt] => 2024-12-10 13:39:36 [post_content_filtered] => [post_parent] => 0 [guid] => http://www.princetonhydro.com/blog/?p=1539 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [7] => WP_Post Object ( [ID] => 802 [post_author] => 3 [post_date] => 2016-10-07 14:52:05 [post_date_gmt] => 2016-10-07 14:52:05 [post_content] =>
FREE BROCHURE DOWNLOAD!
American Littoral Society, Ocean County Soil Conservation District and Princeton Hydro recently held a Stormwater Projects in Action workshop. The workshop focused on a number of 319(h) funded projects designed by Princeton Hydro and implemented by American Littoral Society in the Long Swamp Creek/Lower Toms River sub-watersheds of Barnegat Bay. Those projects exemplified how green infrastructure techniques could be used to retrofit, upgrade and compliment standard stormwater management methods. This included the restoration of healthy soils and the construction/installation of bioretention basins, rain gardens, porous pavement, and sub-surface Manufactured Treatment Devices (MTDs). Event participants learned about the problems affecting Barnegat Bay due to over-development and improper stormwater management. They were presented with examples of the types of green infrastructure solutions that can be implemented in any setting in order to achieve cleaner water and less flooding. A brochure detailing each of the projects and providing an in-depth look at the incredible work being done to save Barnegat Bay was distributed to event attendees. You can download your free copy here:

Princeton Hydro President Dr. Stephen Souza gave two presentations at the event. The first presentation explored the Matrix Scoring Tool that Princeton Hydro's Senior Environmental Scientist Paul Cooper along with Dr. Souza developed to quantitatively evaluate the relative benefit of conducting one stormwater project versus another in a particular area. The 2nd presentation provided an overview of the five stormwater improvement projects that Princeton Hydro conducted as part of the $1,000,000 319(h) grant secured for American Littoral Society. If you're interested in receiving a copy of either presentation, submit a comment below or email us.

Clean water is fundamental to all life.

    [post_title] => Stormwater Projects in Action: Improving Barnegat Bay through Green Infrastructure and Stormwater Management [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => stormwater-projects-in-action [to_ping] => [pinged] => [post_modified] => 2025-10-15 15:26:37 [post_modified_gmt] => 2025-10-15 15:26:37 [post_content_filtered] => [post_parent] => 0 [guid] => http://www.princetonhydro.com/blog/?p=802 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [8] => WP_Post Object ( [ID] => 465 [post_author] => 3 [post_date] => 2016-04-21 19:03:25 [post_date_gmt] => 2016-04-21 19:03:25 [post_content] => Clean water is essential to the health of communities everywhere. That's why it's so important that we all do our part to protect and preserve our precious water resources. Simple steps lead to big leaps in protecting water quality. We've put together a list of eight things you can do to protect water resources in your community and beyond. Let's dive in!

1. Stop mowing near streams and ponds:

Mowing near streams and ponds eliminates the natural protective buffer that tall grasses, shrubs and trees provide. Natural buffers protect against erosion, filter stormwater runoff, reduce harmful pollutant loads and provide habitat for mosquito-eating amphibians, fish, birds and beneficial insects.


2. Reduce lawn fertilizer usage:

One of the best ways to support the health of local water resources is to reduce the use of pesticides and fertilizers. Not only are they costly, but, when over-applied or if applied before a rainstorm, the chemicals runoff directly into our local waterways. Before applying, always remember to test your soil, read product labels and check the forecast. Also consider natural alternatives like compost!


3. Regularly clean storm drains and curbside debris:

Removing debris that collects in nearby stormwater catch basins, storm drains and along curbs promotes cleaner runoff and reduces the amount of pollution and trash entering our waterways. Make a note on your calendar each month to maintain a regular cleaning schedule! Learn more about stormwater management.


4. Host a "Test Your Well" event:

Well testing is a great way to promote groundwater protection, help people understand their role in safeguarding drinking water quality, and provide education around the proper disposal of oil, chemicals, pesticides and medicines. Learn how to host an event in your community!


5. Design and construct a rain garden:

You've heard this one from us before, but, what can we say, we love rain gardens, and rightfully so! They're cost effective, easy to build and do wonders in reducing erosion, promoting ground water recharge, minimizing flooding and removing pollutants from stormwater runoff. Princeton Hydro President Geoff Goll, P.E. recently constructed one in his own yard and documented each of the steps so you can build your own too.


6. Test and treat your ponds and lakes:

Testing your pond/lake water is an important part of preventing problems like harmful weed and algae growth. Princeton Hydro professionals can provide a comprehensive analysis and an array of eco-friendly approaches to control nuisance species and promote the continual health of your pond/lake. Learn more!


7. Reduce erosion and exposed soil on your property:

If you notice erosion occurring on your property, planting native plants can really help! Their roots stabilize the soil, reduce erosion and prevent sediment loading in your waterways, which has a huge impact on the water quality of downstream ponds, lakes and reservoirs!


8. Develop a stewardship plan for your community:

Bring your community together to help preserve its natural resources. Princeton Hydro's team of natural resource scientists can help you get the ball rolling by preparing stewardship plans focused on controlling invasive species and protecting the long-term health of open spaces, forests habitats, wetlands and water-quality in your community.


Thanks for reading our blog and doing your part to improve water quality in your community!

Click here to learn more about Princeton Hydro's efforts to improve water quality and protect natural resources. And, click here to check out our recent blog: "How to Reduce Nutrients & Improve Water Quality with Biochar."

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To prevent harmful algal blooms (HABs) in New Jersey’s largest lake, a clay-based nutrient inactivating technology called Phoslock, is being applied in Lake Hopatcong this week. This is the largest Phoslock treatment to occur in the Northeastern U.S. The Phoslock treatment, which is happening in the southern end of the lake called Landing Channel, is expected to take approximately one week depending on the weather conditions.

[embed]https://youtu.be/BU_lub2UR20[/embed]

Over the course of the 2019 summer season, Lake Hopatcong suffered from large-scale and persistent HABs causing local and county health agencies to close off all beaches and issue advisories over large sections of the lake. These unprecedented conditions had significant negative impacts on the ecological, recreational, and economic resources of the lake and region. In order to combat HABs in this upcoming 2020 summer season, the Lake Hopatcong Commission has partnered with the Lake Hopatcong Foundation, four municipalities (Jefferson, Hopatcong, Mt. Arlington, and Roxbury), two counties (Morris and Sussex), and their environmental consultant, Princeton Hydro, to develop both short- and long-term lake management strategies.

“The negative effects of HABs in our lake last year were numerous, widespread, and in some cases devastating,” recalled Donna Macalle-Holly of Lake Hopatcong Foundation. “It is imperative for every stakeholder to pool our resources to keep it from happening again. Collaboration is the only way to protect public health, as well as the health of New Jersey’s largest lake.”

In an effort to evaluate a variety of innovative in-lake and watershed-based measures to prevent, mitigate, and/or control harmful algal blooms in Lake Hopatcong, the Lake Hopatcong Commission was awarded a $500k grant as part of New Jersey Department of Environmental Protection’s (NJDEP) new $13.5M initiative to reduce and prevent future harmful algal blooms in New Jersey. In addition to the $500k grant, the aforementioned local government and nonprofit stakeholders provided $330k in matching funds to implement and evaluate a variety of ways to address HABs in Lake Hopatcong.

“Our lake community cannot sustain another year like 2019,” said Lake Hopatcong Commission Chairman Ron Smith. “Since the news of our grant award in early March, we have been working with our partners to make sure the projects are implemented in time for the 2020 season.”

This week, the water resource engineering and natural resource management firm, Princeton Hydro—a lake management consultant to Lake Hopatcong for over two decades—is implementing the first and largest innovative measure as part of the NJDEP HABs grant-funded project. This involves treating 50 acres of the southern end of the lake with Phoslock, a clay-based product that inactivates phosphorus in both the water column and the sediments, making this critical nutrient unavailable for algal growth. The Phoslock treatment, which requires proper permitting by NJDEP, is applied as a slurry and will be distributed from a boat. The slurry will temporarily make the water appear turbid, but should disperse approximately two to six hours after each treatment.

“We are expecting the Phoslock treatment to limit the growth of algae and therefore reduce the occurrence of harmful algal blooms in the lake this summer, keeping it open for recreation and business,” said Dr. Fred Lubnow, Director of Aquatic Resources at Princeton Hydro and leading HABs expert. “If this technology is deemed successful and cost-effective in Lake Hopatcong, we could set the precedent for large-scale HABs prevention in other lakes throughout New Jersey, and even across the nation.”

Developed by the Australian national science agency CSIRO, Phoslock is frequently used to strip the water column of dissolved phosphorus, as well as to inactivate phosphorus generated from deep, anoxic sediments. Recently, at a smaller scale, it has been shown to inactivate the mobilization of phosphorus from shallow sediments where there is a mobilization of phosphorus from both chemical and biological processes.

Algae uses phosphate, the biologically available form of phosphorus, as a food source to grow. When there is an excessive amount of phosphorus in a lake, algal growth can be dense and can negatively affect water quality. This excessive plant growth, caused by eutrophication, can both cause a lack of oxygen available, leading to fish kills, as well as produce harmful algal blooms with cyanotoxins, which are harmful to humans and pets.

[caption id="attachment_5095" align="aligncenter" width="550"] Photo credit: SePRO Corporation[/caption]

After Phoslock is applied, it sinks through the water column, binding phosphate as it moves towards the sediment. Once settled at the bottom of the lake, it forms a very thin layer and continues to bind phosphate released from the sediment, thus controlling the release of phosphorus into the lake. One pound of phosphorus has the potential to generate up to 1,100 lbs of wet algae biomass. However, 1.1 tons of Phoslock is capable of removing 24 pounds of phosphorus -- that’s over 26,000 lbs of wet algae biomass not growing in the lake for every 1.1 ton of Phoslock applied. In turn, Phoslock’s ability to suspend biologically available phosphorus is therefore a major step towards improving a lake’s water quality.

As part of the NJDEP HABs grant funding, the stakeholder group will be evaluating the relative effectiveness of this treatment strategy. Because of its shallow depth and separation from the main lake, the Landing Channel area was a good candidate for evaluation of this technology. Princeton Hydro will conduct pre- and post-treatment monitoring of the Phoslock treatment area in order to conduct an objective evaluation of the cost effectiveness of the treatment as a means of preventing the development and/or mitigation of HABs. If the study indicates that Phoslock is a cost-effective treatment, the Lake Hopatcong Commission may consider additional trials in other sections of the lake, if funding is available.

To learn more about HABs, check out our recent blog: [post_title] => Mitigating Harmful Algal Blooms at Lake Hopatcong: Largest Application of Phoslock in Northeast [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => lake-hopatcong-phoslock-treatment [to_ping] => [pinged] => [post_modified] => 2026-03-03 14:59:42 [post_modified_gmt] => 2026-03-03 14:59:42 [post_content_filtered] => [post_parent] => 0 [guid] => https://www.princetonhydro.com/blog/?p=5088 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 4 [filter] => raw ) [comment_count] => 0 [current_comment] => -1 [found_posts] => 9 [max_num_pages] => 1 [max_num_comment_pages] => 0 [is_single] => [is_preview] => [is_page] => [is_archive] => 1 [is_date] => [is_year] => [is_month] => [is_day] => [is_time] => [is_author] => [is_category] => [is_tag] => 1 [is_tax] => [is_search] => [is_feed] => [is_comment_feed] => [is_trackback] => [is_home] => [is_privacy_policy] => [is_404] => [is_embed] => [is_paged] => [is_admin] => [is_attachment] => [is_singular] => [is_robots] => [is_favicon] => [is_posts_page] => [is_post_type_archive] => [query_vars_hash:WP_Query:private] => bbb82cdcbc0f797aaab3436685bb9b74 [query_vars_changed:WP_Query:private] => 1 [thumbnails_cached] => [allow_query_attachment_by_filename:protected] => [stopwords:WP_Query:private] => [compat_fields:WP_Query:private] => Array ( [0] => query_vars_hash [1] => query_vars_changed ) [compat_methods:WP_Query:private] => Array ( [0] => init_query_flags [1] => parse_tax_query ) [query_cache_key:WP_Query:private] => wp_query:522652c3738e3a5f38702bbf44509bcf )

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