Newsletter Sign-up Email a Friend Printer Friendly Format Translate This Page Text Size Small Medium Large


Mapping & Modeling Technology

DEP uses a series of linked computer models to aid in short-term operational decisions about the water supply and long-term planning and assessment of the City’s water supply system and watershed management programs. DEP’s models can simulate the transport of water and contaminants within the watershed and reservoirs, as well as the generation and transport of pollution from the land surface to the reservoirs. In this capacity, DEP’s comprehensive computer modeling system is used to explore alternative future scenarios and examine how the water supply system and its components may behave in response to changes in land use, population, climate, watershed or reservoir management, and system operations.

Geographic Information System (GIS)

DEP manages a comprehensive GIS that allows watershed staff to analyze and evaluate information and programs in a unique spatial and temporal context (space and time). DEP regularly acquires, updates, and develops new GIS data layers, creates watershed program databases, performs GIS analyses and research, and produces maps and statistical reports. On average, DEP staff generate over 500 GIS watershed maps per month and support dozens of watershed data requests from City, State and federal agencies.

DEP’s GIS staff train and support other DEP staff, interns, and local government agents in the use of Global Positioning Systems (GPS) for project-specific data gathering efforts such as field inventories or facilities mapping. GIS staff also provide remote sensing support in the analysis of satellite or aerial imagery for land use mapping.

Of particular importance to watershed protection is DEP’s Watershed Lands Information System (WaLIS) — a custom database application that manages information about watershed lands and resources owned by New York City and its neighbors. WaLIS integrates GIS data analyses, relational database management, document management, and reporting capabilities to specifically support natural resource management and land acquisition projects, as well as other watershed programs, applications, and decisions.

Reservoir Levels

Current: 66.3%

Normal: 76.6%