A GIS-Based Model to Identify Sensitive Water Resource Properties in Need of Protection 2009 Watershed Science and Technical Conference September 14 & 15, West Point, NY Jen Zhang Watershed Protection Specialist New Jersey Water Supply Authority (NJWSA)

NJWSA Water Supply System Independent State Authority – 1981 Operates state owned water supply facilities Round Valley Spruce Run Delaware & Raritan Canal Raritan System Manasquan

Location of NJWSA Water Supply Systems

Source Water Protection Program in NJWSA Source Water Protection (SWP) has long been recognized as one of the most effective means for ensuring long-term viability of water supply and maintenance of water quality. The Authority created and instituted a comprehensive SWP program including the creation of a Watershed Protection Unit in 1999 and a Land and Resource Preservation Program in The Watershed Protection Unit (WPU) was created to improve the protection of water resources and to develop and implement projects that improve protection of water supply for the Authority and its customers. The Land and Resource Preservation Program was designed to identify, acquire, and manage critical watershed parcels toward protection of water supply. GIS has been heavily involved since the start of the program to help identify critical properties for protection.

Acquisition Approach Focus – preservation of contiguous lands Strategy – link land acquisition and zoning benefits NJWSA customers support through water supply rates Partner with State & local governments, land trusts

Target Areas 6,900 acres (240 parcels) in 6 project areas targeted for preservation back in 2002 only in five municipalities Strategy now extends outside of original target areas

The acquisition target area extends from its original five to forty municipalities The target area extends from original 6,900 acres to a total of 185,500 acres Focus on: Sensitive Water Resource Area Location of Target Area

 2,700 acres preserved to date (2009) 1,119 acres in active negotiations

The GIS Model Project Background Dramatic land use changes over the past few years in the North and South Branch Raritan River Watershed and the Lockatong and Wichecheoke Creek Watershed Area – our target acquisition project area. Importance of protection - It is time to identify and protect the most sensitive water resources before they will be lost forever Project Committee was formed in 2002 to create a GIS database to help open space acquisition. Database was revisited and upgraded in Dec for “water resource” specific criteria The GIS procedures involves remote sensing, aerial photography and available geographic information system (GIS) data.

The GIS Model Constrains This project focused on water resource protection, it does not address all land conservation goals. The GIS model focused on remaining lands instead of the existing preserved (open space and farmland) or developed lands. Use readily available GIS data, was limited by data availability and how current the data is (eg LU/LC)

Acquire Sensitive Water Resources Stream corridors Headwaters Wetlands Flood hazard areas Critical habitats Riparian forests Prime ground water recharge and aquifer recharge areas Highly erodible soils ……

The Database Model and Layers Class ValuesWeight K-Factor (low) (medium) (high)30 Land UseWater0 Wetlands0 Forest10 Urban20 Agriculture30 Barren Land30 Slopes0 -- 5% % % % % %40 >50%50 Class ValuesErosion Susceptibility Erosion Susceptibility Theme 0Not erodible land Low - medium low Medium - medium high >20001High - extremely high

The Composite Map of Water Resource Area The Composite Map

The Individual Water Resource Area – Riparian Area

The Individual Water Resource Area – Highly Erodible Soils

Property Analysis The property analysis can show - The % of water resource area on each property (all the water resource areas were weighted equally and grouped into a composite critical area) The type and the location of water resource area on each property.

Property Boundary Overlay with Sensitive Water Resource Area % of Properties in Sensitive Water Resource Area

Application of this GIS Model Rank properties by their % included in water resource area Rank properties by property size Check what water resource environmental features located in each property and where Assess and evaluate potential properties for future acquisition Avoid isolated open space – consider proximity to existing preserved open space Use the findings from this project to assist in soliciting state funds Can lead to improvements to municipal ordinances, master plans, environmental resource inventories, zoning density, open space preservation plans, etc

All potential properties will be first evaluated through this database to determine the number of criteria present If a property ranks highly enough, a second level of evaluation will be applied. This second tier will be a case- by-case critical review. All the criteria are weighted equally in this database. Further scoring might be added based on project requirement. Application of the GIS Model - Continued

A comprehensive approach that relies on strong partnerships at all levels Tel: Open Space Acquisition in the Raritan Basin