FreshkillsPark will be the largest park developed in New York City in over a century

The transformation of what was once the world’s largest landfill into a sustainable park makes the project a symbol of renewal and an expression of how we can re-imagine reclaimed landscapes

Freshkills Park - The Freshkills Park Alliance

The Park Plan
Freshkills Park will be the largest park developed in New York City in over a century. The transformation of what was once the world’s largest landfill into a sustainable park makes the project a symbol of renewal and an expression of how we can re-imagine reclaimed landscapes. Landfill infrastructure is essential to the Park’s design, and it adds to the project’s complexity. The park’s design, engineering, and ecological restoration emphasize environmental sustainability and public concern for human impact.

The Fresh Kills Landfill stopped accepting household garbage in 2001. By then, DSNY had already installed systems for containing and collecting landfill byproducts and started closing sections of the landfill. With the decision to shut down Fresh Kills, the Municipal Art Society (MAS) collaborated with the City of New York to sponsor an international design competition, run by the Department of City Planning. The process resulted in an illustrative park plan, known as the Draft Master Plan, designed by landscape architecture firm Field Operations.  The basic framework of the plan integrates 2,200 acres of open grasslands, waterways and engineered structures into one cohesive and dynamic unit.

Freshkills Park will host a variety of public spaces and facilities for social, cultural and physical activity, learning and play. The site is large enough to support many activities and programs, including nature hikes, kayaking, and large scale public art, among many others. As the park is built in phases, a calendar of free tours and events provides early access for learning and exploration opportunities. Primary program streams include  research, art, education, and recreation such as hiking, birdwatching, bicycling, running, and kayak tours.
Ecological Resurgence

Freshkills Park is home to a variety of habitats with a diverse array of wildlife. As a reclaimed landscape in a densely urban region, the site holds great potential for providing habitat needs to vulnerable species. Since landfill closure, a variety of plants and animals have been thriving. Native grasses were planted on the capped landfill mounds, and rare grassland birds now make their home in what has become one of the largest grassland habitats in the region. Freshkills Park presents unique opportunities to study the processes of developing ecosystems in an urban setting, and to adaptively manage the reclaimed landscape to encourage species productivity.
Engineered Systems

The Freshkills Park landscape has many natural features, but it is highly engineered. The landfill is maintained by the Department of Sanitation (DSNY) and overseen by the New York State Department of Environmental Conservation (DEC). The landfill mounds are sealed with a cap, which includes layers of soil and geotextiles. A system of wells, trenches, and pipes collects landfill byproducts underground and sends them to nearby treatment plants. Air, surface water and groundwater monitoring are conducted on a regular basis. To learn more, visit the Landfill Engineering page.

Freshkills is defined by four landfill mounds, with tidal creeks running through the center of the landscape. An expansive network of paths, recreational waterways, and enhanced access through a system of park drives will help create an animated, interconnected park. Future plans include a publicly accessible road system that will create a connection between the West Shore Expressway (Route 440) and Richmond Avenue and provide access to the different areas of the park.

In 2006, NYC Parks assumed responsibility for implementing the project, using the Draft Master Plan as a conceptual guide. Visit NYC Parks’ Planning and Building Parks page to learn more about the agency’s overall planning and building process.
One Project at a Time

Freshkills Park is being built out in phases, and most of the site remains closed to the public. The park’s edges are opening first so that people can enjoy new parkland as soon as possible. Projects that provide direct connection to the communities surrounding the park have been given the highest priority, and some have already opened:

    Schmul Park in the Travis neighborhood was redesigned in 2012.
    Owl Hollow Soccer Fields in Arden Heights opened in 2013.
    The New Springville Greenway near the Staten Island Mall opened in 2015.

Construction is currently underway for phase one of North Park. The South Park Anchor Park project is currently in design, with plans for multipurpose fields and trails adjacent to Owl Hollow. As more sections of the park open, the unusual combination of natural and engineered beauty – including creeks, wetlands, expansive meadows and spectacular vistas of the New York City region – will be accessible. See Design and Construction Updates for more information.

Landfill Engineering

Covering, Stabilizing, Maintaining

The Fresh Kills Landfill is covered with different layers of soil, geotextiles, and a geomembrane. These layers stabilize landfilled waste, separate the waste from the environment and park visitors and prevent the release of landfill gas to the atmosphere. Along with the landfill cap, a collection of swales, down chutes, and retention ponds collect and manage stormwater to prevent erosion to the cap caused by rain water. The New York State Department of Environmental Conservation (NYSDEC) requires a landfill cap be installed on all closed landfills.

At Freshkills Park, the landfill cap is 3 – 12 feet deep and contains the following layers:

    Municipal solid waste was landfilled at Freshkills for 53 years. Naturally occurring clay-like soil at the very bottom of the waste layer helps prevent vertical migration of leachate and waste. The waste itself was covered with layers of soil, on a regular basis, a technique used to create stability within the mounds and to minimize odors.

    Soil Barrier Layer
    Directly on top of landfilled waste is at least two feet of soil known as the soil barrier layer. This layer covers the garbage and ensures the hills are stable. It has varying degrees of thickness so the mounded waste could be shaped into the rolling hills seen at Freshkills Park today. Each hill has been graded to be between 4% and 33% to facilitate storm water drainage.

    Gas Venting Layer
    The gas venting layer is a thick geotextile made to promote collection and absorption of gas in soil. This specific type of geotextile consists of two synthetic fabrics heat-bonded to either side of a hard plastic netting. By laying this geotextile over the soil barrier layer, any stray gases moving up through the lower layers will be absorbed by the geotextile. The empty space created by the hard plastic netting allows the particles to move laterally, eventually ending up in the landfill gas collection system.

    Impermeable Plastic Liner
    The impermeable plastic liner is a different type of geotextile made from a thin, durable plastic material. Neither water nor gas can move through this layer. It provides separation between the waste layer below and clean soil above as well as preventing the escape of gases upwards into the atmosphere and the migration of rain water downwards into the waste. Tiny micro-spikes along the surface of the impermeable liner help keep the liner from slipping.

    Drainage Layer
    A geotextile similar to the gas venting layer is used as a drainage layer. It functions the same as the gas venting layer, but in reverse. The drainage layer prevents water from traveling downward through the top layers of the landfill cap.  Water then moves laterally through the geotextile to the stormwater down chutes and away from mounded waste.

    Barrier Protection Material
    The barrier protection material is made of at least two feet of sandy soil placed on top of the drainage layer. This soil protects the geotextiles underneath.

    Planting Soil
    Lastly, at least six inches of clean planting soil is spread over the barrier protection material. The soil is seeded with a native plant mix, whose roots help stabilize the mounds and absorb water.

Over time, the landfill subsides as materials break down and gas and leachate are removed from the mounds. Because of this landfill settlement, the height of the mounds decreases by 10 to 15 percent over time. Approximately half of this settlement will occur in the first five to ten years after the final waste is placed, with further settlement continuing at a decreasing rate for at least another 20 years.

Storm Water Management
A collection of swales, downchutes, and detention basins move storm water away from the soil layers on the landfill cap. If not managed, storm water could gather in puddles on the hills, eroding the upper layers of the cap. The mounds themselves have slopes graded to facilitate drainage. Swales direct water to down chutes that flow into storm water control basins. Storm water is held in the basins until any sediment settles to the bottom of the pond. The water is then discharged into surrounding waterways.
Collection and Processing
Landfills produce two byproducts: leachate and landfill gas. Freshkills Park has collection systems designed to capture and treat these byproducts. The collection systems are maintained by the Department of Sanitation (DSNY) and overseen by the New York State Department of Environmental Conservation (DEC). The systems will be decommissioned once monitoring data collected by DSNY and reviewed by DEC shows that they are no longer needed.

Landfill Gas Collection System
Landfill gas is created as anaerobic bacteria feed on decomposing waste. The gas is a mixture of methane, carbon dioxide, and small amounts of non-methane organic compounds (NMOCs). The landfill cap prevents landfill gas from migrating into the atmosphere. Below the cap, a network of wells, pipes and blowers collect landfill gas from the capped landfill mounds and send it to an onsite purification plant.


    Prior to 1982, the landfill gas at Fresh Kills was burned before being released into the atmosphere. Combustion transforms the methane in landfill gas into carbon dioxide, which is less harmful to the atmosphere. Since 1982, the landfill gas has been treated and recycled instead of burned.
    Landfill gas wells extend down into the waste layer. These vertical wells have holes that allow particles of landfill gas inside. The wells are connected to a network of lateral pipes, which are connected to nearby flare stations.
    The three flare stations at Freshkills Park can be easily identified by their large white stacks. The flare station blowers create a vacuum that pulls landfill gas into the vertical wells and through the network of lateral pipes to a purification plant.


    At the landfill gas purification plant, the gas is refined into pipeline-grade natural gas through a series of physical and chemical reactions.
    When the landfill gas first arrives at the plant, it is compressed and cooled until any water vapor condenses. The condensate is collected and sent to the nearby leachate treatment plant.
    The compressed gas goes through a pre-treatment process that removes hydrogen sulfide, followed by a treatment process to remove carbon dioxide.
    The City of New York sells the purified natural gas to National Grid, which distributes the gas to Staten Island residents for cooking and heating fuel.
    As of 2018, the system collects about 3 million cubic feet of landfill gas per day, purified to produce about 1.5 million cubic feet of methane.


    As is typical in landfills, the amount of gas produced by the landfill has decreased over time. Monitoring data indicates that the methane concentrations in the landfill gas are now safely below regulated thresholds. DSNY is making plans to decommission the gas collection and treatment system in the next few years.
    Decommissioning is a multi-step process that involves testing, data collection and reporting to DEC to obtain their agreement. DSNY has proposed an initial pilot test during which the collection and treatment system is turned off and air quality at passive vent locations is tested on a regular basis. DEC will review the monitoring data before making a final decision about shutting down the systems.
    Once decommissioning is approved, both the collection and treatment systems will be permanently shut down and then demolished. The above ground extraction wells and flare stations will be removed from the mounds.
    Once the system is demolished, the remaining gas will be passively vented through an open pipe located at the former flare stations.

Leachate Collection System

Leachate is created when rainwater percolates through decomposing garbage and picks up particles, including potential contaminants, from the garbage along the way. At Freshkills Park, the soil underlying the waste is made of a fine silt clay with low permeability. The clay has prevented the leachate from migrating into deeper layers of soils below the landfill. Around the mounds, trenches, cut-off walls, pipes, and pumps are designed to collect the leachate that migrates laterally through the mounds. The collected leachate is pumped to a treatment plant that separates the water from waste materials.

Collection & Containment

    Perforated pipes are installed in trenches 6-8 feet deep around the periphery of the mounds. Two of the mounds (East and West) also have containment (slurry) walls installed for an additional level of containment. These systems collect leachate and prevent off-site migration.
    The pipes are connected to pumping stations that pump the leachate to the treatment plant.


    The leachate treatment plant was updated in 1994. As of 2018, it treats about 300,000 gallons of leachate per day.
    At the plant, leachate is treated biologically with anaerobic bacteria that break down any remaining organic matter.
    Sodium hydroxide and aluminum sulfate are added to the leachate to transform any soluble metals into their non-soluble (solid) form.
    The mixture of solids and liquid is then sent to a clarifier where the solids settle out and are removed.
    The solids are dewatered and compressed into sludge cakes that can be transported to other facilities in New York City for further treatment.
    The remaining liquid is filtered through sand, which captures any remaining solids, before being discharged into the Arthur Kill.
    Before being discharged to the Arthur Kill, clean water is tested to ensure that it meets the discharge limits set by DEC.


    DSNY is in the process of decommissioning the leachate collection system on all four mounds, one by one.
    DSNY started with North and South Mounds because they have been closed the longest and were expected to have less leachate.
    On the basis of long term monitoring data, DEC approved DSNY’s request to shut off the leachate collection system at North and South mounds and collect groundwater monitoring data to determine whether there was any impact on the quality of the surrounding groundwater.
    No impact was found, so DSNY has shut down the leachate collection system on these two mounds and removed the above-ground equipment.
    Active leachate collection systems remain in operation on East and West Mounds.


Air, surface water and groundwater monitoring are conducted on a regular basis to ensure that the landfill infrastructure functions properly.

Water and Sediment Monitoring

At Freshkills Park, groundwater monitoring wells are installed at intervals of about 500 feet in the shallow groundwater around each landfill mound, every 750 feet in the groundwater zones down-gradient of the mounds, and every 1,500 feet in the groundwater zones up-gradient of the mounds. In total, there are 238 groundwater monitoring wells, 116 of which are shallow well, 61 are intermediate depth wells, and 61 are deep bedrock wells. Groundwater monitoring is performed quarterly at each well.  Data are evaluated for trends and submitted to NYSDEC in an annual monitoring report.

Annual surface water monitoring is conducted in the Fresh Kills, Main, and Richmond Creeks within the landfill boundaries, and sediment quality in the creeks is tested during a biennial monitoring program. Surface water and sediment sampling is performed at a total of 14 sampling stations. Four of these stations are also monitored for benthic ecology (the study of organisms living in and on the sea floor) at both the intertidal and subtidal zones.

Air Quality Monitoring

Air quality monitoring at Freshkills Park is done on a daily, monthly, quarterly, and yearly basis depending on the contaminant being monitored. Among the compounds monitored are methane, carbon monoxide, particulate matter and sulfur dioxide. Approximately 57 possible emissions points associated with landfill infrastructure and operations are monitored.

All of the air quality monitoring done at Freshkills Park is reviewed by NYSDEC, the agency responsible for enforcing standards set out in the federal Clean Air Act. The Clean Air Act requires each state to meet the National Ambient Air Quality Standards (NAAQS), which establishes the maximum amount of six contaminants (Carbon Monoxide, Lead, Ozone, Nitrogen Dioxide, Particulate Matter, and Sulfur Dioxide) allowed in the air.

Research-Based Water Monitoring

The Freshkills Park Water Monitoring Program is a project designed to allow participants to gain direct experience conducting real scientific research by monitoring the water quality within Freshkills Park. The water quality data provides insight into wildlife changes at the site.

Participants measure for a variety of water properties and their findings will then be put to use in ongoing efforts to maintain and support the safety and ecological diversity of the Staten Island watershed.
 Find this and more information here