construction services

Existing drainage systems in the area were limited and not adequate to drain stormwater runoff. Streets were flooding regularly. Groundwater was approximately two feet below grade which limited the function of the on-site sanitary system for the homes. All parcels were within the zero to two year groundwater travel time to the Great South Bay. Several studies have documented the impacts of excessive nitrogen from sanitary systems in reducing dissolved oxygen levels to the detriment of aquatic life and in supporting harmful algal blooms. In conjunction with this study to provide sanitary sewers, we investigated the feasibility of making storm drainage-related improvements to help address existing flooding conditions related to the proposed sanitary sewer improvements. The report identified potential drainage improvements that could be implemented while the roadways were disturbed during the construction of the sanitary sewers. The drainage improvements included the installation of approximately 4,750 linear feet of porous concrete gutter, along with drainage pipe and underground stone storage space along the shoulders of each of the roadways. In addition, a shallow vegetated stormwater management basin was proposed to temporarily store excess runoff during storm events. This system was incorporated to help alleviate flooding during storm events and improve drainage in this flat, low-lying section of Patchogue. During design, we conducted a utility coordination meeting with representatives of National Grid, the Village DPW and the Suffolk County Water Authority. Our personnel also met with homeowners to review the proposed installation location of the on-site pump station and low pressure sewer connection. Plans were submitted to and approved by the Suffolk County Department of Health Services. We worked with the Dormitory Authority of the State of New York (DASNY), Suffolk County and the Village of Patchogue in order to receive funding through two DASNY grants, an Infrastructure Program Grant provided by Suffolk County, and the Village of Patchogue Sewer Fund. Remaining funds were bonded by the Village. We provided a resident engineer during construction. Construction phase services included full time construction inspection, shop drawing review, review of contractor payment requests and periodic meetings. During construction the project scope was expanded to include the abandonment of the existing on site sanitary system at each home.

H2M’s GIS specialists compiled field documentation and tabular data of storm water assets collected through field survey services to satisfy the NYS SPDES MS4 program. Once all storm water assets were compiled, the GIS data and the associated field documents were packaged for submission to the NYSDEC compliance with the SPDES MS4 program. H2M’s GIS specialists converted tabular data to GIS and a KMZ file to store map details for simplified viewing in Google Earth. The KMZ file allows the Village to view the storm water infrastructure as an overlay on Google Earth imagery. This allows the Village to efficiently locate the infrastructure to its surrounding area and view a summary of the data collected for each structure. The data summary in the GIS map includes a link to individual field sheets and photos.

H2M was retained as Program Manager supporting a FEMA funded Hazard Mitigation Program (FHMP) for a major New York electric utility. Administered by FEMA under Section 406 of the Stafford Act, H2M’s role is to provide overall Program Management. The project includes multiple engineering consultants and construction contractors to be coordinated and integrated. Program management includes project controls and scheduling for the design and construction of 1,025 miles of storm hardened mainline distribution circuits and the installation of Automated Sectionalizing Units (ASUs). The H2M Program team also acts as the lead Construction Manager to document and review all construction activity. This includes safety program implementation, incident review, construction tracking, field review and documentation, materials and design reconciliation, and RFI and change request reviews. H2M’s scope includes tracking and ensuring that all required permits are filed and obtained prior to construction. This activity includes coordination with many stakeholders including the design professionals, contractors, municipalities and many other third parties.

At the Water Authority of Western Nassau County’s (WAWNC) Plants 28 and 30, 7.0 MGD of potable drinking water is supplied to consumers through a series of four groundwater wells. Iron concentrations at both plants had exceeded the established standard and rendered the existing treatment ineffective. The presence of iron in the groundwater had also severely impacted the well itself, leading to a considerable reduction in capacity. WAWNC made the decision to install an iron treatment system to remove the iron from the groundwater—making sure to keep in mind that the site in question was located in the middle of a residential neighborhood. Sand filtration technology is a proven, cost-effective approach for the removal of iron from drinking water. WAWNC elected to install a pressurized sand filtration system that would be fully automated, which simplifies operations and requires only routine maintenance from plant personnel. To situate this plant in the residential neighborhood, all aspects of the plant, including filters, the control room, chemical storage, piping and equipment, were designed to blend in, utilizing features consistent with surrounding properties. Sustainable design elements such as LED lighting and cementitious siding were included to lessen the project’s impact on the environment. Since inception, the result has been iron-free water, reducing rusty water complaints and ensuring a clean, reliable source of drinking water to WAWNC’s customers for years to come. The completed design met and exceeded the client’s desire for a sustainable-oriented facility that blends in with the existing neighborhood. The automated controls of the facility will continue to add to the cost efficiency of this plant.

The United States Postal Service’s (USPS) Morgan Processing and Distribution Center (P&DC) is one of the largest mail processing facilities in the U.S. Built in 1933, it was designated an historic landmark in 1986. With 1,600 windows and 2.2 million interior square feet, it also boasts the largest green roof in New York City (2.5 acres) and one of the largest in the country. Seasonal fluctuations in mail volume were creating overloads on the building electrical system. H2M was brought in to assess the problem, develop alternative solutions and assist the USPS in implementation. The USPS was facing stiff penalties from the electrical utility for the seasonal loads. Conducting an intensive electrical building survey, H2M developed an alternative solution that involved a reduction in electricity used for air conditioning chilled water. Diverting that additional power to other transformers and switchgear alleviated loads from the overloaded switchboards. The outcome was a leveling of loads which avoided the seasonal fluctuations, allowing the postal service to stay on schedule processing and delivering the mail.

West Harbor Drive was a four-lane roadway through a primarily residential area of the Village of Bayville. A large percentage of vehicular traffic used the road to bypass the adjacent business district, and limited traffic control devices encouraged speeding. The roadway offered no sidewalk or shoulders; therefore, pedestrians walked on the grass and bicyclists rode in the vehicle travel lanes. The Village sought to increase the safety of its residents by decreasing incidences of speeding and providing a safe location for bicyclists and pedestrians to enjoy the roadway. After completing a preliminary assessment and design, H2M designed the project to include: the installation of bike lanes in each direction; reduction from four lanes to two lanes; installation of a striped center median; dedicated left turn lanes; a sidewalk on the south side of West Harbor Drive, and installation of ADA-accessible ramps and crosswalks. This project was a Locally Administered Federal Aid Project (LAFAP) and was designed in accordance with the associated guidelines.

H2M recently provided land surveying, engineering, architectural design services, and site planning for a new major upgrade to the Town of North Hempstead’s Manhasset Valley Park. The nearly 18-acre park consisted of mostly passive parkland, including woodlands, a natural grass baseball field, playground, surface parking, with walking trails spread throughout the park. Important environmental features of the park included mature trees, a stream, a pond, and wetlands, which required our engineers to perform wetland mapping, tree identification, and a detailed topographic survey of the site. Constraint and opportunity maps identified potential locations for the new park facilities to minimize impacts to environmentally-sensitive areas. Concept site plan alternatives led to the placement of the new illuminated, multi-purpose synthetic field for soccer, lacrosse, field hockey and football; a new fully handicap accessible children’s playground; new ADA compliant bathrooms; and 69-stall parking field. The existing baseball field was reconstructed to make it compliant with Williamsport Little League specifications. Along with design and engineering, H2M provided construction administration services for the new field, a batting cage, site development, lighting and irrigation. Permit support included permits for freshwater wetlands through NYSDEC, a sewer connection permit through the Great Neck Water Pollution Control District, and a backflow prevention permit through the Manhasset Lakeville Water District. The new park was re-dedicated in Spring 2013 with a field at the park named after Jim Brown, NFL Hall of Famer and Manhasset High School Alumnus.

With Wells 7-1 and 7-2 impacted by contamination, H2M was retained by the South Huntington Water District (SHWD) to evaluate and determine the most viable and cost-effective VOC-removal treatment technology. H2M prepared an engineering study for SHWD to evaluate available VOC removal alternatives, which concluded that granular-activated carbon (GAC) pressure filters would be the best treatment solution for the client. H2M later went on to design and prepare construction documents for a new GAC treatment facility and would be able to treat a total of 4.0 MGD through four carbon pressure filters. The scope of the project included rehabilitation of two 2.0 MGD ground water wells, modifications to existing site piping, and the demolition of the existing pump houses. A 2,780-square-foot masonry building was constructed to house Well 7-2, four 12-foot diameter GAC pressure filters, a 4,000 gallon horizontal caustic storage tank, calcium hypochlorite tablet chlorinators and chemical metering pumps for pH adjustment and disinfection. A 245-square-foot masonry building was built on site to house Well 7-1. There is also a 500 kW standby generator to feed power to both wells in the event of a power outage.