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WP_Query Object ( [query] => Array ( [sector] => consultants ) [query_vars] => Array ( [sector] => consultants [error] => [m] => [p] => 0 [post_parent] => [subpost] => [subpost_id] => [attachment] => [attachment_id] => 0 [name] => [pagename] => [page_id] => 0 [second] => [minute] => [hour] => [day] => 0 [monthnum] => 0 [year] => 0 [w] => 0 [category_name] => [tag] => [cat] => [tag_id] => [author] => [author_name] => [feed] => [tb] => [paged] => 1 [meta_key] => [meta_value] => [preview] => [s] => [sentence] => [title] => [fields] => all [menu_order] => [embed] => [category__in] => Array ( ) [category__not_in] => Array ( ) [category__and] => Array ( ) [post__in] => Array ( ) [post__not_in] => Array ( ) [post_name__in] => Array ( ) [tag__in] => Array ( ) [tag__not_in] => Array ( ) [tag__and] => Array ( ) [tag_slug__in] => Array ( ) [tag_slug__and] => Array ( ) [post_parent__in] => Array ( ) [post_parent__not_in] => Array ( ) [author__in] => Array ( ) [author__not_in] => Array ( ) [search_columns] => Array ( ) [ignore_sticky_posts] => [suppress_filters] => [cache_results] => 1 [update_post_term_cache] => 1 [update_menu_item_cache] => [lazy_load_term_meta] => 1 [update_post_meta_cache] => 1 [post_type] => [posts_per_page] => 10 [nopaging] => [comments_per_page] => 5 [no_found_rows] => [taxonomy] => sector [term] => consultants [order] => DESC ) [tax_query] => WP_Tax_Query Object ( [queries] => Array ( [0] => Array ( [taxonomy] => sector [terms] => Array ( [0] => consultants ) [field] => slug [operator] => IN [include_children] => 1 ) ) [relation] => AND [table_aliases:protected] => Array ( [0] => ph_term_relationships ) [queried_terms] => Array ( [sector] => Array ( [terms] => Array ( [0] => consultants ) [field] => slug ) ) [primary_table] => ph_posts [primary_id_column] => ID ) [meta_query] => WP_Meta_Query Object ( [queries] => Array ( ) [relation] => [meta_table] => [meta_id_column] => [primary_table] => [primary_id_column] => [table_aliases:protected] => Array ( ) [clauses:protected] => Array ( ) [has_or_relation:protected] => ) [date_query] => [queried_object] => WP_Term Object ( [term_id] => 1299 [name] => Consultant [slug] => consultants [term_group] => 0 [term_taxonomy_id] => 1299 [taxonomy] => sector [description] => [parent] => 0 [count] => 9 [filter] => raw [term_order] => 0 ) [queried_object_id] => 1299 [request] => SELECT SQL_CALC_FOUND_ROWS ph_posts.ID FROM ph_posts LEFT JOIN ph_term_relationships ON (ph_posts.ID = ph_term_relationships.object_id) WHERE 1=1 AND ( ph_term_relationships.term_taxonomy_id IN (1299) ) AND ((ph_posts.post_type = 'project' AND (ph_posts.post_status = 'publish' OR ph_posts.post_status = 'acf-disabled'))) GROUP BY ph_posts.ID ORDER BY ph_posts.menu_order, ph_posts.post_date DESC LIMIT 0, 10 [posts] => Array ( [0] => WP_Post Object ( [ID] => 19292 [post_author] => 1 [post_date] => 2026-03-06 13:46:46 [post_date_gmt] => 2026-03-06 13:46:46 [post_content] => The Goethals Bridge Replacement Project resulted in unavoidable impacts to 4.929 acres of wetlands and open water associated with the Arthur Kill, requiring the creation of 15.39 acres of mudflat, low marsh, high marsh, and scrub/shrub habitat; and preservation of 3.91 acres of existing low marsh/high marsh and open water habitat. Princeton Hydro worked with the United States Army Corps of Engineers (USACE) – New York District and the New York State Department of Environmental Conservation (NYSDEC) on the development of an acceptable monitoring program that was implemented in 2019. As stipulated in the NYSDEC-issued permit, the monitoring program had to follow the New York State Salt Marsh Restoration and Monitoring Guidelines (Guidelines) established in 2000. Working closely with USACE and NYSDEC and following the program specified within the Guidelines, Princeton Hydro established five transects and eighteen associated 1m2 quadrat locations along the five transects. Each transect represented a cross section of the various ecological communities present between Old Place Creek and the upper extent of the mitigation site. The ecological communities monitored across each transect included low marsh, high marsh, transitional zones between low marsh and high marsh, and scrub/shrub, respectively. [gallery link="none" columns="2" ids="19307,19305"] The following metrics were calculated within each 1m2 quadrat: overall percent cover and species composition comprising the observed percent cover. Within each 1m2 quadrat, a 0.25m2 portion of the quadrat was analyzed for stem density and plant height as outlined within the Guidelines. Additionally, the entire mitigation site was investigated for the presence of invasive species with subsequent mapping developed and incorporated into an adaptive management plan. This was then implemented to address the presence of common reed (Phragmites australis). Annual monitoring reports were prepared and submitted to both USACE and NYSDEC detailing the results of the monitoring effort with a focus on the established transects and 1m2 quadrats along each transect. A section of the reports was dedicated to the development of an adaptive management plan to ensure the mitigation site satisfied the requisite 85% vegetative cover comprised of desirable, native species. [post_title] => NYSDEC Wetland Monitoring - Old Place Creek Mitigation Site [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => nysdec-wetland-monitoring-old-place-creek-mitigation-site [to_ping] => [pinged] => [post_modified] => 2026-03-06 13:46:46 [post_modified_gmt] => 2026-03-06 13:46:46 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?post_type=project&p=19292 [menu_order] => 0 [post_type] => project [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 18036 [post_author] => 1 [post_date] => 2025-08-05 17:20:25 [post_date_gmt] => 2025-08-05 17:20:25 [post_content] => The Gloucester County Solid Waste Complex (GCSWC) was required to implement a grassland bird habitat and hibernacula mitigation and maintenance plan, totaling 71.34-acres, within an undeveloped southern portion of GCSWC land (Site). This mitigation and maintenance plan was required to offset an expansion of the existing landfill into an area which presently provides suitable grassland bird habitat. In addition to the creation of grassland bird habitat, the Permit Modification also required the implementation of periodic grassland bird surveys to document the development of the grassland and to ensure that suitable grassland habitat has been created which supports breeding grassland bird species. Princeton Hydro assessed the existing ecological communities within a portion of the undeveloped land within the GCSWC, which was being targeted for the creation of grassland bird habitat and a hibernacula mitigation and maintenance plan. This effort identified the existing ecological communities, documented plant species, provided recommendations for grassland habitat enhancement within the existing ecological communities where warranted, provided guidelines for hibernaculum creation, and provided seed mix recommendations to create quality grassland bird habitat. This report, the “Grassland Habitat Ecological Communities Analysis”, served as the basis for the habitat creation efforts on-Site. Concomitant to the implementation of the recommended restoration measures outlined in the Grassland Habitat Ecological Communities Analysis document, Princeton Hydro developed a systematic monitoring plan for the avian species on-Site, titled “The Grassland Bird Species and Hibernacula Monitoring Plan”. In 2023, the recommended management measures were implemented, including the application of the recommended upland and wet meadow seed mixes installed within a 70-acre portion of the Site. The seed mixes were selected to include native, desirable grassland flora which are preferred by grassland nesting avifauna. In addition to the creation of grassland bird habitat, approximately 1.34-acres of wildlife hibernacula, designed by Princeton Hydro, were installed. Subsequent to habitat implementation measures, it was determined in early 2024 that the grassland seed mix had germinated successfully, and in response, the grassland bird species monitoring was initiated for the 2024 breeding season. Results of the first monitoring of the grassland indicate that it has developed quality habitat in its initial growing season. Additionally, the created habitat was supporting a number of grassland obligate and grassland edge breeding bird species. Point count and incidental avian surveys of the Site documented the presence of grassland and grassland edge breeding birds throughout the breeding season. These species included New Jersey State Threatened Breeding Species Grasshopper Sparrow, Horned Lark, and American Kestrel, and Special Concern Breeding Species Field Sparrow, Bank Swallow, and Brown Thrasher. In addition to these species which possess a New Jersey State listing designation, a number of additional grassland obligate, open country, and grassland edge species were documented, including a rare New Jersey breeding species in Dickcissel, along with Blue Grosbeak, Indigo Bunting, Song Sparrow, Red-winged Blackbird, Orchard Oriole, and Eastern Kingbird. Confirmations of successful breeding (i.e. nests, fledged young, feeding young, etc.) were observed in many of these species, indicating that the Site is already productive for the targeted grassland avifauna. [post_title] => Development of Grassland Bird Species and Hibernacula Monitoring Plan/Grassland Bird Surveys [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => development-of-grassland-bird-species-and-hibernacula-monitoring-plan-grassland-bird-surveys [to_ping] => [pinged] => [post_modified] => 2025-08-05 17:22:43 [post_modified_gmt] => 2025-08-05 17:22:43 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?post_type=project&p=18036 [menu_order] => 0 [post_type] => project [post_mime_type] => [comment_count] => 0 [filter] => raw ) [2] => WP_Post Object ( [ID] => 17622 [post_author] => 1 [post_date] => 2025-06-03 11:47:38 [post_date_gmt] => 2025-06-03 11:47:38 [post_content] => Princeton Hydro was part of a two-firm team tasked with the completion of Phase II detail scour analyses for the New Jersey Turnpike Authority (NJTA), a major state-wide transportation authority. Princeton Hydro was specifically tasked with the completion of scour analyses for 13 individual major highway bridges. These bridges were distributed throughout the state and included structures in both the coastal plain and piedmont physiographic provinces. The road crossings at the focus of the study range from single lane exit ramps to five-lane single direction major highways. The average daily traffic load of combined 13 road crossings which were studied is 1.3 million vehicles per day. The detailed Phase II studies were conducted on structures which were previously identified during separate Phase I scour investigations and Biennial Bridge Inspection Reports. Inspections and investigations ultimately either confirmed the existing Federal Highway Authority Structure Inventory and Appraisal of the Nation’s Bridges (SI&A) codes including Items 61 (Channel and Channel Protection), Item 71 (Waterway Adequacy) and Item 113 (Scour Critical Bridges). Princeton Hydro provided a wide range of services as it related to the scour assessments. These services included field inspection service planning and logistics as well and watercraft access to bridge structures. In-field engineering inspections of bridge structures with a focus on scour were also completed for the 13 structures. These inspections included the collection of photographs of the bridge and surrounding channel conditions as well as the collection of representative soil samples. The soil samples were then delivered to our in-house soil laboratory, which is accredited under the American Association of State Highway and Transportation Officials (AASHTO) Accreditation Program (AAP), for analysis with the results of the soil analyses being applied in the scour analysis hydraulic calculations. Our engineering services included a detailed review of previous documentation for each bridge including original as-built drawing, previous inspection reports, and other National Bridge Inspection Standards (NBIS) reporting. The Phase II detailed scour analysis also included a hydrologic analysis for each road crossing with consequent hydraulic modeling of the bridge structure and stream channel being performed in HEC-RAS. Results from HEC-RAS were then used to conduct additional scour analysis in the Federal Highway Administration Hydraulic Toolbox. [post_title] => New Jersey Turnpike Authority Phase II Detail Scour Analysis [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => new-jersey-turnpike-authority-phase-ii-detail-scour-analysis [to_ping] => [pinged] => [post_modified] => 2025-06-03 11:47:38 [post_modified_gmt] => 2025-06-03 11:47:38 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?post_type=project&p=17622 [menu_order] => 0 [post_type] => project [post_mime_type] => [comment_count] => 0 [filter] => raw ) [3] => WP_Post Object ( [ID] => 15857 [post_author] => 1 [post_date] => 2024-10-17 19:00:08 [post_date_gmt] => 2024-10-17 19:00:08 [post_content] => Princeton Hydro and BRS, Inc. were contracted by the Cities of Trenton and Salem to perform climate change-related hazard vulnerability assessments to inform municipal resilience action plans. The work was completed as part of the Resilient NJ Program, an assistance program run by the NJDEP Bureau of Climate Resilience Planning. The program supports local and regional climate resilience planning by bringing together planners, engineers, designers, and other experts to address flood- and climate-related hazards. The Cities of Trenton and Salem, like many across the region, already experience climate related hazards such as extreme heat and flooding which disrupts traffic patterns, impacts infrastructure, damages property, and puts lives at risk. These climate-related hazards are expected to worsen over the next century and beyond due to climate change. In order to prepare for and adapt to climate-related hazards, our team worked to map extreme heat and flooding hazards across these cities under both current climate conditions and future projections. We then assessed the geographic distribution of these hazards to identify at-risk populations and city resources, such as critical infrastructure, community assets, cultural and historic resources, and land developments. These assessments will be used to develop resilience action plans, which will guide future climate hazard policies, planning, and projects in Trenton and Salem. [caption id="attachment_15855" align="aligncenter" width="1596"] Salem[/caption] [caption id="attachment_15856" align="aligncenter" width="1585"] Trenton[/caption] A key component of our climate hazard vulnerability assessments was to not only provide information needed for planning and decision-making, but to also provide information to the general public. Princeton Hydro and BRS facilitated several public information sessions. The Princeton Hydro-BRS Team provided a primer on climate hazards and presented the vulnerability assessment findings along with a Q&A session. This process invited public feedback and maximized public participation. [post_title] => Resilient NJ - Trenton and Salem [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => resilient-nj-trenton-and-salem [to_ping] => [pinged] => [post_modified] => 2024-10-17 19:00:08 [post_modified_gmt] => 2024-10-17 19:00:08 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?post_type=project&p=15857 [menu_order] => 0 [post_type] => project [post_mime_type] => [comment_count] => 0 [filter] => raw ) [4] => WP_Post Object ( [ID] => 15852 [post_author] => 1 [post_date] => 2024-10-17 18:32:42 [post_date_gmt] => 2024-10-17 18:32:42 [post_content] => The Lower Raritan Center Mitigation Site is comprised of over 120 acres with approximately 110 acres of proposed planting, situated along the Raritan River waterfront. The project site is located on a portion of the U.S. Department of Defense’s former Raritan Arsenal. As part of a Master Plan developed by GreenVest LLC, the goals for the site include the creation of mitigation value and ecological uplift in concert with creating opportunities for future responsible redevelopment of other portions of the larger site for commercial and transportation resources. The primary project objectives include restoration, enhancement, and preservation of freshwater wetlands, open water, and upland maritime forest; riparian enhancement and creation; and invasive species management. During the late-summer months of 2023, approximately 120 acres of Phragmites (also called common reed) were sprayed with Habitat®, an EPA-registered systemic herbicide, which contains the active ingredient imazapyr. The herbicide application was conducted using an amphibious Marsh Master MM1 machine equipped with a custom sprayer system. The Marsh Master herbicide application took approximately 20 days to complete and was expected to achieve approximately 90% control of the common reed growing within the site. [gallery size="medium" link="none" columns="2" ids="15851,15850"] To ensure the continued mitigation of this highly aggressive and invasive species, additional herbicide applications took place in 2024 and another is expected to be completed in 2025. During the winter of 2024, Princeton Hydro used the new Marsh Master 2MX-KC-FH amphibious machine to mow, roll, and plow the dead common reed stalks. The operation started with the Marsh Master and rear mounted hydraulic mower attachment; the entire site was mowed using this attachment. Designated areas of the project site containing high amounts of phragmites were cleared a second time, this time with the Marsh Master’s rear mounted roller/chopper attachment and front mounted hydraulic vegetation blade. The roller/chopper attachment “mulched” the common reed stalks further to expose more of the substrate. The front mounted vegetation blade was then used to push or “plow” the common reed stalks to expose even more of the substrate. Exposing the substrate allows for easier planting efforts for native species and provides a suitable environment for native seed bank establishment. Upon completion of the second herbicide application, the site will be ready for construction and planting of desirable, native and biodiverse vegetation. Future herbicide applications will be conducted using handheld equipment to avoid any damage to the new plantings. [post_title] => Lower Raritan Center Mitigation Site Phragmites Control [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => lower-raritan-center-mitigation-site-phragmites-control [to_ping] => [pinged] => [post_modified] => 2024-10-17 18:46:04 [post_modified_gmt] => 2024-10-17 18:46:04 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?post_type=project&p=15852 [menu_order] => 0 [post_type] => project [post_mime_type] => [comment_count] => 0 [filter] => raw ) [5] => WP_Post Object ( [ID] => 15396 [post_author] => 1 [post_date] => 2024-06-17 17:46:11 [post_date_gmt] => 2024-06-17 17:46:11 [post_content] => Evergreen Environmental, LLC retained Princeton Hydro, LLC to provide scientific, engineering, permitting, herbicide treatment, and construction oversight support to deliver compensatory wetland mitigation credits required for the expansion of the Garden State Parkway in southern New Jersey. [gallery link="none" size="medium" columns="2" ids="15395,15392"] Princeton Hydro was responsible for completing hydrologic assessments, conducting wetland delineations and habitat surveys, coordinating regulatory agency involvement for sensitive species occurrence, developing wetland mitigation concept designs, obtaining permits for final design plans, issuing contractor bid specifications, and overseeing project implementation. The project also required regular interactions with members of the New Jersey Wetland Mitigation Unit of the NJDEP. To compensate for wetland disturbances associated with widening of the Garden State Parkway, Princeton Hydro developed a mitigation plan for an 8.4-acre former Christmas tree farm. The mitigation design included a hydrologic study, a water budget, wetland delineation, a swamp pink survey, and a flood hazard permit. The mitigation design included elements of wetland preservation, enhancement, creation, and restoration. After the first growing season, the mitigation site possessed 92% cover and 97% survivorship of woody plant material. The site also possessed a vernal habitat component that supported several frog species. Upon completion, the mitigation site was conveyed to U. S. Fish and Wildlife Service to become part of the Edwin B. Forsythe National Wildlife Refuge. [gallery link="none" columns="2" size="medium" ids="15391,15393"] [post_title] => Garden State Parkway Gunning River Freshwater Wetland Mitigation [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => garden-state-parkway-gunning-river [to_ping] => [pinged] => [post_modified] => 2024-11-20 15:49:11 [post_modified_gmt] => 2024-11-20 15:49:11 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?post_type=project&p=15396 [menu_order] => 0 [post_type] => project [post_mime_type] => [comment_count] => 0 [filter] => raw ) [6] => WP_Post Object ( [ID] => 14593 [post_author] => 1 [post_date] => 2024-03-06 21:27:07 [post_date_gmt] => 2024-03-06 21:27:07 [post_content] => Princeton Hydro worked collaboratively with GreenVest to design the 25-acre Lawrence Brook wetland mitigation site. The site is situated at the confluence of the Lawrence Brook and the Raritan River and is an important urban/estuarine mixing zone providing habitat for wading birds, waterfowl, fish, and invertebrates. Its tidally influenced wetlands were extensively ditched for mosquito control and completely dominated by the invasive Common Reed (Phragmites australis). [gallery link="none" columns="2" ids="14594,14596"] This mitigation project provided compensatory mitigation for the former National Lead site redevelopment project. The primary objective was to eliminate Common Reed and replace the site with a more desirable and species-rich plant community. The project also included a wetland creation component. Princeton Hydro prepared the engineering plans in a collaborative effort with GreenVest. The design included clearing and grubbing of invasive species, excavation of accreted sediments within the wetland restoration areas to achieve optimal marsh elevations, placement of excavated material within proposed upload forested areas, re-vegetation of restoration areas with native plant species, and installation of wildlife exclusion systems and fencing to prevent herbivory. Although the plan emphasized the restoration of estuarine wetland, the project also included forested/scrub-shrub freshwater wetlands, maritime upland forest, and riparian buffers. [gallery columns="2" link="none" ids="14597,14598"] Princeton Hydro was also retained to manage the invasive species control program for the project site, which targeted the elimination of Common Reed, and allowed a number of desirable tidal wetland species to colonize the site. Subsequent to completion of several treatments, the dead stalks and thatch were removed from the marsh plain to facilitate the establishment of planted material as well as allow for plant species present in the marsh’s seed bank to emerge. The wetland responded extremely well to this restoration project and the site is dominated by a species-rich intertidal plant community that includes several rare species. [post_title] => Lawrence Brook Wetland Mitigation Site [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => lawrence-brook-wetland-mitigation-site [to_ping] => [pinged] => [post_modified] => 2024-03-06 21:27:07 [post_modified_gmt] => 2024-03-06 21:27:07 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?post_type=project&p=14593 [menu_order] => 0 [post_type] => project [post_mime_type] => [comment_count] => 0 [filter] => raw ) [7] => WP_Post Object ( [ID] => 11527 [post_author] => 1 [post_date] => 2022-09-20 16:38:50 [post_date_gmt] => 2022-09-20 16:38:50 [post_content] => The Turtle Creek Mitigation site is one of several sites identified to offset impacts to freshwater wetlands, coastal wetlands, and threatened and endangered species habitat resulting from the widening of the Garden State Parkway Milepost 30-80. The 259-acre Turtle Creek Mitigation Site was identified to offset impacts to threatened and endangered species including Northern Pine Snake (Pituophis melanoleucus), Pine Barrens Treefrog (Hyla andersonii), Barred Owl (Strix varia), Timber Rattlesnake (Crotalus horridus), and Red-headed Woodpecker (Melanerpes erythrocephalus), among others. Princeton Hydro was contracted to conduct a two-phase survey to first identify, map, and assess the habitat on the site and second to conduct directed surveys in the field to verify the species’ presence. [gallery link="none" ids="11530,11529,14401"] The identification, mapping, and screening-level assessment of on-site habitats used aerial photographs and ESRI ArcMap®. Once habitats were mapped, they were ground-verified as well as evaluated for the potential for each habitat to support the target listed species. The second phase of the project involved conducting directed surveys to determine the presence of target species. The surveys were conducted from spring through autumn of 2007. Surveys were scheduled and conducted on the site during the time of year that the species would be most readily observed, such as during breeding, nesting, or flowering times. Additionally, survey methods were specific to each species such as conspecific vocalization playback for amphibian and bird species, time constrained searches in habitat identified as suitable for that species during their most active time, and random incidental encounter using transect searches through their suitable habitat. These methods are accepted survey techniques and increase the likelihood of detecting the target species. The surveys and subsequent report summarized the results and facilitated the approval of the site as an offset to suitable habitat impact that will result from the Garden State Parkway Widening project. [post_title] => Turtle Creek Mitigation Site Threatened and Endangered Species Surveys [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => turtle-creek-mitigation-site-threatened-and-endangered-species-surveys [to_ping] => [pinged] => [post_modified] => 2024-01-19 02:25:05 [post_modified_gmt] => 2024-01-19 02:25:05 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?post_type=project&p=11527 [menu_order] => 35 [post_type] => project [post_mime_type] => [comment_count] => 0 [filter] => raw ) [8] => WP_Post Object ( [ID] => 11544 [post_author] => 1 [post_date] => 2022-09-20 17:12:20 [post_date_gmt] => 2022-09-20 17:12:20 [post_content] => Princeton Hydro was contracted by AKRF to conduct Tier 1 and Tier 2 Oyster Sampling & Classification at the Tappan Zee Bridge Hudson River Crossing Project. Nine sites were selected during Tier 1 for subsequent investigation based on sediment quality data and other relevant factors. Two of the sites were located north of the Tappan Zee Bridge along the eastern bank of the Hudson River. The remaining sites were south of the bridge; five of these extended from immediately adjacent to the bridge south to the Piermont pier on the western shipping channel margin while the remaining two sites were on the eastern shipping channel margin. The study was conducted in two phases. The first phase included sampling all nine sites, with ten ponar dredge grabs conducted within each area. After the first phase was completed, the data was summarily analyzed to identify which five areas should be resampled at a higher frequency focusing on oyster frequency, capture density, age-class distribution, and sediment/habitat suitability. Once identified the five selected areas were resampled; with fifteen ponar dredge grabs then collected in each area. [gallery link="none" columns="2" ids="11545,11546"] In addition to live processing of the oysters (counts and shell dimensions) in the field, a number of oysters were retained and transferred to the New York Harbor School faculty at Cornell University to initiate an overall Hudson River/Tappan Zee Bridge Crossing oyster propagation study. Our results showed that higher quality oysters could successfully be relocated prior to the installation of the bridge abutments. [post_title] => Oyster Sampling, Classification & Relocation Project [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => oyster-sampling-classification-relocation-project [to_ping] => [pinged] => [post_modified] => 2024-07-11 13:56:43 [post_modified_gmt] => 2024-07-11 13:56:43 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?post_type=project&p=11544 [menu_order] => 37 [post_type] => project [post_mime_type] => [comment_count] => 0 [filter] => raw ) ) [post_count] => 9 [current_post] => -1 [before_loop] => 1 [in_the_loop] => [post] => WP_Post Object ( [ID] => 19292 [post_author] => 1 [post_date] => 2026-03-06 13:46:46 [post_date_gmt] => 2026-03-06 13:46:46 [post_content] => The Goethals Bridge Replacement Project resulted in unavoidable impacts to 4.929 acres of wetlands and open water associated with the Arthur Kill, requiring the creation of 15.39 acres of mudflat, low marsh, high marsh, and scrub/shrub habitat; and preservation of 3.91 acres of existing low marsh/high marsh and open water habitat. Princeton Hydro worked with the United States Army Corps of Engineers (USACE) – New York District and the New York State Department of Environmental Conservation (NYSDEC) on the development of an acceptable monitoring program that was implemented in 2019. As stipulated in the NYSDEC-issued permit, the monitoring program had to follow the New York State Salt Marsh Restoration and Monitoring Guidelines (Guidelines) established in 2000. Working closely with USACE and NYSDEC and following the program specified within the Guidelines, Princeton Hydro established five transects and eighteen associated 1m2 quadrat locations along the five transects. Each transect represented a cross section of the various ecological communities present between Old Place Creek and the upper extent of the mitigation site. The ecological communities monitored across each transect included low marsh, high marsh, transitional zones between low marsh and high marsh, and scrub/shrub, respectively. [gallery link="none" columns="2" ids="19307,19305"] The following metrics were calculated within each 1m2 quadrat: overall percent cover and species composition comprising the observed percent cover. Within each 1m2 quadrat, a 0.25m2 portion of the quadrat was analyzed for stem density and plant height as outlined within the Guidelines. Additionally, the entire mitigation site was investigated for the presence of invasive species with subsequent mapping developed and incorporated into an adaptive management plan. This was then implemented to address the presence of common reed (Phragmites australis). Annual monitoring reports were prepared and submitted to both USACE and NYSDEC detailing the results of the monitoring effort with a focus on the established transects and 1m2 quadrats along each transect. A section of the reports was dedicated to the development of an adaptive management plan to ensure the mitigation site satisfied the requisite 85% vegetative cover comprised of desirable, native species. 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The Goethals Bridge Replacement Project resulted in unavoidable impacts to 4.929 acres of wetlands and open water associated with the Arthur Kill, requiring the creation of 15.39 acres of mudflat, low marsh, high marsh, and scrub/shrub habitat; and preservation of 3.91 acres of existing low marsh/high marsh and open water habitat. Princeton Hydro worked with the United States Army Corps of Engineers (USACE) – New York District and the New York State Department of Environmental Conservation (NYSDEC) on the development of an acceptable monitoring program that was implemented in 2019. As stipulated in the NYSDEC-issued permit, the monitoring program had to follow the New York State Salt Marsh Restoration and Monitoring Guidelines (Guidelines) established in 2000. Working closely with USACE and NYSDEC and following the program specified within the Guidelines, Princeton Hydro established five transects and eighteen associated 1m2 quadrat locations along the five transects. Each transect represented a cross section of the various ecological communities present between Old Place Creek and the upper extent of the mitigation site. The ecological communities monitored across each transect included low marsh, high marsh, transitional zones between low marsh and high marsh, and scrub/shrub, respectively.
The following metrics were calculated within each 1m2 quadrat: overall percent cover and species composition comprising the observed percent cover. Within each 1m2 quadrat, a 0.25m2 portion of the quadrat was analyzed for stem density and plant height as outlined within the Guidelines. Additionally, the entire mitigation site was investigated for the presence of invasive species with subsequent mapping developed and incorporated into an adaptive management plan. This was then implemented to address the presence of common reed (Phragmites australis). Annual monitoring reports were prepared and submitted to both USACE and NYSDEC detailing the results of the monitoring effort with a focus on the established transects and 1m2 quadrats along each transect. A section of the reports was dedicated to the development of an adaptive management plan to ensure the mitigation site satisfied the requisite 85% vegetative cover comprised of desirable, native species.
The Gloucester County Solid Waste Complex (GCSWC) was required to implement a grassland bird habitat and hibernacula mitigation and maintenance plan, totaling 71.34-acres, within an undeveloped southern portion of GCSWC land (Site). This mitigation and maintenance plan was required to offset an expansion of the existing landfill into an area which presently provides suitable grassland bird habitat. In addition to the creation of grassland bird habitat, the Permit Modification also required the implementation of periodic grassland bird surveys to document the development of the grassland and to ensure that suitable grassland habitat has been created which supports breeding grassland bird species.
Princeton Hydro assessed the existing ecological communities within a portion of the undeveloped land within the GCSWC, which was being targeted for the creation of grassland bird habitat and a hibernacula mitigation and maintenance plan. This effort identified the existing ecological communities, documented plant species, provided recommendations for grassland habitat enhancement within the existing ecological communities where warranted, provided guidelines for hibernaculum creation, and provided seed mix recommendations to create quality grassland bird habitat. This report, the “Grassland Habitat Ecological Communities Analysis”, served as the basis for the habitat creation efforts on-Site.
Concomitant to the implementation of the recommended restoration measures outlined in the Grassland Habitat Ecological Communities Analysis document, Princeton Hydro developed a systematic monitoring plan for the avian species on-Site, titled “The Grassland Bird Species and Hibernacula Monitoring Plan”. In 2023, the recommended management measures were implemented, including the application of the recommended upland and wet meadow seed mixes installed within a 70-acre portion of the Site. The seed mixes were selected to include native, desirable grassland flora which are preferred by grassland nesting avifauna. In addition to the creation of grassland bird habitat, approximately 1.34-acres of wildlife hibernacula, designed by Princeton Hydro, were installed. Subsequent to habitat implementation measures, it was determined in early 2024 that the grassland seed mix had germinated successfully, and in response, the grassland bird species monitoring was initiated for the 2024 breeding season.
Results of the first monitoring of the grassland indicate that it has developed quality habitat in its initial growing season. Additionally, the created habitat was supporting a number of grassland obligate and grassland edge breeding bird species. Point count and incidental avian surveys of the Site documented the presence of grassland and grassland edge breeding birds throughout the breeding season. These species included New Jersey State Threatened Breeding Species Grasshopper Sparrow, Horned Lark, and American Kestrel, and Special Concern Breeding Species Field Sparrow, Bank Swallow, and Brown Thrasher. In addition to these species which possess a New Jersey State listing designation, a number of additional grassland obligate, open country, and grassland edge species were documented, including a rare New Jersey breeding species in Dickcissel, along with Blue Grosbeak, Indigo Bunting, Song Sparrow, Red-winged Blackbird, Orchard Oriole, and Eastern Kingbird. Confirmations of successful breeding (i.e. nests, fledged young, feeding young, etc.) were observed in many of these species, indicating that the Site is already productive for the targeted grassland avifauna.
Princeton Hydro was part of a two-firm team tasked with the completion of Phase II detail scour analyses for the New Jersey Turnpike Authority (NJTA), a major state-wide transportation authority. Princeton Hydro was specifically tasked with the completion of scour analyses for 13 individual major highway bridges. These bridges were distributed throughout the state and included structures in both the coastal plain and piedmont physiographic provinces. The road crossings at the focus of the study range from single lane exit ramps to five-lane single direction major highways. The average daily traffic load of combined 13 road crossings which were studied is 1.3 million vehicles per day.
The detailed Phase II studies were conducted on structures which were previously identified during separate Phase I scour investigations and Biennial Bridge Inspection Reports. Inspections and investigations ultimately either confirmed the existing Federal Highway Authority Structure Inventory and Appraisal of the Nation’s Bridges (SI&A) codes including Items 61 (Channel and Channel Protection), Item 71 (Waterway Adequacy) and Item 113 (Scour Critical Bridges).
Princeton Hydro provided a wide range of services as it related to the scour assessments. These services included field inspection service planning and logistics as well and watercraft access to bridge structures. In-field engineering inspections of bridge structures with a focus on scour were also completed for the 13 structures. These inspections included the collection of photographs of the bridge and surrounding channel conditions as well as the collection of representative soil samples.
The soil samples were then delivered to our in-house soil laboratory, which is accredited under the American Association of State Highway and Transportation Officials (AASHTO) Accreditation Program (AAP), for analysis with the results of the soil analyses being applied in the scour analysis hydraulic calculations.
Our engineering services included a detailed review of previous documentation for each bridge including original as-built drawing, previous inspection reports, and other National Bridge Inspection Standards (NBIS) reporting. The Phase II detailed scour analysis also included a hydrologic analysis for each road crossing with consequent hydraulic modeling of the bridge structure and stream channel being performed in HEC-RAS. Results from HEC-RAS were then used to conduct additional scour analysis in the Federal Highway Administration Hydraulic Toolbox.
Princeton Hydro and BRS, Inc. were contracted by the Cities of Trenton and Salem to perform climate change-related hazard vulnerability assessments to inform municipal resilience action plans.
The work was completed as part of the Resilient NJ Program, an assistance program run by the NJDEP Bureau of Climate Resilience Planning. The program supports local and regional climate resilience planning by bringing together planners, engineers, designers, and other experts to address flood- and climate-related hazards. The Cities of Trenton and Salem, like many across the region, already experience climate related hazards such as extreme heat and flooding which disrupts traffic patterns, impacts infrastructure, damages property, and puts lives at risk. These climate-related hazards are expected to worsen over the next century and beyond due to climate change.
In order to prepare for and adapt to climate-related hazards, our team worked to map extreme heat and flooding hazards across these cities under both current climate conditions and future projections. We then assessed the geographic distribution of these hazards to identify at-risk populations and city resources, such as critical infrastructure, community assets, cultural and historic resources, and land developments. These assessments will be used to develop resilience action plans, which will guide future climate hazard policies, planning, and projects in Trenton and Salem.
A key component of our climate hazard vulnerability assessments was to not only provide information needed for planning and decision-making, but to also provide information to the general public. Princeton Hydro and BRS facilitated several public information sessions. The Princeton Hydro-BRS Team provided a primer on climate hazards and presented the vulnerability assessment findings along with a Q&A session. This process invited public feedback and maximized public participation.
The Lower Raritan Center Mitigation Site is comprised of over 120 acres with approximately 110 acres of proposed planting, situated along the Raritan River waterfront. The project site is located on a portion of the U.S. Department of Defense’s former Raritan Arsenal.
As part of a Master Plan developed by GreenVest LLC, the goals for the site include the creation of mitigation value and ecological uplift in concert with creating opportunities for future responsible redevelopment of other portions of the larger site for commercial and transportation resources. The primary project objectives include restoration, enhancement, and preservation of freshwater wetlands, open water, and upland maritime forest; riparian enhancement and creation; and invasive species management.
During the late-summer months of 2023, approximately 120 acres of Phragmites (also called common reed) were sprayed with Habitat®, an EPA-registered systemic herbicide, which contains the active ingredient imazapyr. The herbicide application was conducted using an amphibious Marsh Master MM1 machine equipped with a custom sprayer system. The Marsh Master herbicide application took approximately 20 days to complete and was expected to achieve approximately 90% control of the common reed growing within the site.
To ensure the continued mitigation of this highly aggressive and invasive species, additional herbicide applications took place in 2024 and another is expected to be completed in 2025.
During the winter of 2024, Princeton Hydro used the new Marsh Master 2MX-KC-FH amphibious machine to mow, roll, and plow the dead common reed stalks. The operation started with the Marsh Master and rear mounted hydraulic mower attachment; the entire site was mowed using this attachment. Designated areas of the project site containing high amounts of phragmites were cleared a second time, this time with the Marsh Master’s rear mounted roller/chopper attachment and front mounted hydraulic vegetation blade. The roller/chopper attachment “mulched” the common reed stalks further to expose more of the substrate. The front mounted vegetation blade was then used to push or “plow” the common reed stalks to expose even more of the substrate. Exposing the substrate allows for easier planting efforts for native species and provides a suitable environment for native seed bank establishment.
Upon completion of the second herbicide application, the site will be ready for construction and planting of desirable, native and biodiverse vegetation. Future herbicide applications will be conducted using handheld equipment to avoid any damage to the new plantings.
Evergreen Environmental, LLC retained Princeton Hydro, LLC to provide scientific, engineering, permitting, herbicide treatment, and construction oversight support to deliver compensatory wetland mitigation credits required for the expansion of the Garden State Parkway in southern New Jersey.
Princeton Hydro was responsible for completing hydrologic assessments, conducting wetland delineations and habitat surveys, coordinating regulatory agency involvement for sensitive species occurrence, developing wetland mitigation concept designs, obtaining permits for final design plans, issuing contractor bid specifications, and overseeing project implementation. The project also required regular interactions with members of the New Jersey Wetland Mitigation Unit of the NJDEP.
To compensate for wetland disturbances associated with widening of the Garden State Parkway, Princeton Hydro developed a mitigation plan for an 8.4-acre former Christmas tree farm. The mitigation design included a hydrologic study, a water budget, wetland delineation, a swamp pink survey, and a flood hazard permit. The mitigation design included elements of wetland preservation, enhancement, creation, and restoration. After the first growing season, the mitigation site possessed 92% cover and 97% survivorship of woody plant material. The site also possessed a vernal habitat component that supported several frog species.
Upon completion, the mitigation site was conveyed to U. S. Fish and Wildlife Service to become part of the Edwin B. Forsythe National Wildlife Refuge.
Princeton Hydro worked collaboratively with GreenVest to design the 25-acre Lawrence Brook wetland mitigation site. The site is situated at the confluence of the Lawrence Brook and the Raritan River and is an important urban/estuarine mixing zone providing habitat for wading birds, waterfowl, fish, and invertebrates. Its tidally influenced wetlands were extensively ditched for mosquito control and completely dominated by the invasive Common Reed (Phragmites australis).
This mitigation project provided compensatory mitigation for the former National Lead site redevelopment project. The primary objective was to eliminate Common Reed and replace the site with a more desirable and species-rich plant community. The project also included a wetland creation component. Princeton Hydro prepared the engineering plans in a collaborative effort with GreenVest. The design included clearing and grubbing of invasive species, excavation of accreted sediments within the wetland restoration areas to achieve optimal marsh elevations, placement of excavated material within proposed upload forested areas, re-vegetation of restoration areas with native plant species, and installation of wildlife exclusion systems and fencing to prevent herbivory. Although the plan emphasized the restoration of estuarine wetland, the project also included forested/scrub-shrub freshwater wetlands, maritime upland forest, and riparian buffers.
Princeton Hydro was also retained to manage the invasive species control program for the project site, which targeted the elimination of Common Reed, and allowed a number of desirable tidal wetland species to colonize the site. Subsequent to completion of several treatments, the dead stalks and thatch were removed from the marsh plain to facilitate the establishment of planted material as well as allow for plant species present in the marsh’s seed bank to emerge. The wetland responded extremely well to this restoration project and the site is dominated by a species-rich intertidal plant community that includes several rare species.
The Turtle Creek Mitigation site is one of several sites identified to offset impacts to freshwater wetlands, coastal wetlands, and threatened and endangered species habitat resulting from the widening of the Garden State Parkway Milepost 30-80.
The 259-acre Turtle Creek Mitigation Site was identified to offset impacts to threatened and endangered species including Northern Pine Snake (Pituophis melanoleucus), Pine Barrens Treefrog (Hyla andersonii), Barred Owl (Strix varia), Timber Rattlesnake (Crotalus horridus), and Red-headed Woodpecker (Melanerpes erythrocephalus), among others. Princeton Hydro was contracted to conduct a two-phase survey to first identify, map, and assess the habitat on the site and second to conduct directed surveys in the field to verify the species’ presence.
The identification, mapping, and screening-level assessment of on-site habitats used aerial photographs and ESRI ArcMap®. Once habitats were mapped, they were ground-verified as well as evaluated for the potential for each habitat to support the target listed species.
The second phase of the project involved conducting directed surveys to determine the presence of target species. The surveys were conducted from spring through autumn of 2007. Surveys were scheduled and conducted on the site during the time of year that the species would be most readily observed, such as during breeding, nesting, or flowering times. Additionally, survey methods were specific to each species such as conspecific vocalization playback for amphibian and bird species, time constrained searches in habitat identified as suitable for that species during their most active time, and random incidental encounter using transect searches through their suitable habitat. These methods are accepted survey techniques and increase the likelihood of detecting the target species.
The surveys and subsequent report summarized the results and facilitated the approval of the site as an offset to suitable habitat impact that will result from the Garden State Parkway Widening project.
Princeton Hydro was contracted by AKRF to conduct Tier 1 and Tier 2 Oyster Sampling & Classification at the Tappan Zee Bridge Hudson River Crossing Project. Nine sites were selected during Tier 1 for subsequent investigation based on sediment quality data and other relevant factors. Two of the sites were located north of the Tappan Zee Bridge along the eastern bank of the Hudson River. The remaining sites were south of the bridge; five of these extended from immediately adjacent to the bridge south to the Piermont pier on the western shipping channel margin while the remaining two sites were on the eastern shipping channel margin.
The study was conducted in two phases. The first phase included sampling all nine sites, with ten ponar dredge grabs conducted within each area. After the first phase was completed, the data was summarily analyzed to identify which five areas should be resampled at a higher frequency focusing on oyster frequency, capture density, age-class distribution, and sediment/habitat suitability. Once identified the five selected areas were resampled; with fifteen ponar dredge grabs then collected in each area.
In addition to live processing of the oysters (counts and shell dimensions) in the field, a number of oysters were retained and transferred to the New York Harbor School faculty at Cornell University to initiate an overall Hudson River/Tappan Zee Bridge Crossing oyster propagation study. Our results showed that higher quality oysters could successfully be relocated prior to the installation of the bridge abutments.
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