Desarrollo de los distintos programas

The Central Delaware Tributaries run in a narrow band along the Delaware River from northern Hunterdon County, Holland Township to southwestern Monmouth County in Millstone Township. This WMA encompasses 24 municipalities and 272 square miles of land.

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Water Bodies

Highlands Region subwatersheds are located in the most northern area of Hunterdon County in Holland and Alexandria Townships. These include the Hakihokake, Harihokake and Nishiskawick Creek subwatersheds, which drain approximately 63 square miles. There are three additional subwatersheds in WMA 11, all located outside the Highlands Region that include Lockatong/Wickecheoke Creek, Alexauken/Moore/Jacobs Creek, and Assunpink Creek.

Topography and Geology

Land elevations in the south begin near sea level in Trenton and develop into rolling hills of 300 to 400 feet in the center of this WMA. Elevations rise to over 800 feet in the Musconetcong Mountains, along the watershed’s northern boundary within the Hakihokake, Harihokake, and Nishiskawick watersheds.

Highlands portions of the watersheds in the Musconetcong Mountains contain the oldest Precambrian rocks in New Jersey, formed 1.1 billion to 750 million years ago. Geology of the Highlands Region is generally characterized by granite and gneiss. The Precambrian rocks are considered to be unproductive aquifers. Slopes in the Highland Region watersheds of this WMA can be greater than 15% in grade.

Soils

Lakehurst-Lakewood-Atsion soils are found in the upper reaches of the watershed; Penn-Reaville- Kinesville from the red shale rocks in the middle reaches and Rowland-Pope-Birdsville in the lower reaches.

Wildlife Resources

There are seven natural resource priority habitat areas in Hunterdon County. They include Hunterdon Milford Bluffs, an important red shale community; the Jarves Road site; Devil’s Tea Table; Byram; Treasure Island; Raven Rock; and Holocombe Island. The Sourland Mountain forest and Assunpink Wildlife Management Area are also within this WMA.

Water Supply

The Delaware River supplies water supply for most of the population in the entire WMA. With respect to the Highlands Region specifically, Holland and Alexandria Townships are totally reliant on ground water for their potable supplies.

Land Use

Land use around the Central Delaware Tributaries is largely evenly split evenly between agriculture, forest, and urban land. Hunterdon County has reportedly lost 71% of its wetlands to agriculture between the years 1940 to 1970. Urban lands in the Central Delaware Tributaries had increased by approximately 15% between 1986 and 1995.

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This section provides a detailed description of current surface water quality conditions in the Highlands Region based upon assessments generated for the New Jersey 2006 Integrated Report, as compiled by the NJDEP.

Section 303(d) of the Federal Water Pollution Control Act (33 U.S.C. 1313(c)), commonly known as the Clean Water Act, requires states to identify “Impaired Waters” where specific designated uses are not fully supported. Known as the 303(d) list, this list identifies the name of the water body and the pollutant or pollutants causing the water body to be listed as impaired. Section 305(b) of the Clean Water Act also requires states to periodically assess and report on the overall quality of their waters. With guidance from USEPA, in 2002 the NJDEP integrated the 303(d) report with the 305(b) report into one report titled the New Jersey Water Quality Monitoring and Assessment Report (Integrated Report) (NJDEP, 2006af).

Based on information included in the 2006 Integrated Report, surface water quality overall was found to be moderately higher in the Highlands compared to conditions statewide. However, bacterial impairment was more extensive in the Highlands than elsewhere in the State. A full 91% of assessed water body units in the Highlands are not supporting primary contact recreation due to unacceptable sanitary quality and 65% are not supporting aquatic life support use. The most common water quality parameters in violation of surface water quality standards were bacteria, temperature and phosphorus, in that order. Water quality is presented both in overall terms and in detail at the water body level.

Nine sites located within the Highlands Region were reviewed for water quality trends covering the period from 1984 to 2004. Of the constituents assessed, dissolved oxygen (DO), DO saturation, and nitrate (NO3) levels indicated stable conditions over time. Total dissolved solids (TDS) and specific conductance (an indirect measure of chloride) displayed upward trends, indicating decreasing water quality. Ammonia and total phosphorus showed declining trends, or improving water quality. Total nitrogen displayed mixed results, with four sites indicating no measurable trend and four sites indicating improving conditions.

INTRODUCTION 

This report provides a recent snapshot of the surface water quality within or directly bordering the Highlands Region. The information is taken from the December 2006 New Jersey Integrated Water

Quality Monitoring and Assessment Report. Water quality information contained here is divided into two

parts. The first is a Highlands-wide summary of the degree to which designated uses of the state’s waters are supported or not, based on an assessment of the water quality for HUC14 subwatersheds contained either wholly or partially within the Highlands Region. It summarizes the overall use support status, if a water body does or does not support a designated use in the Highlands, and compares this to the use support status of New Jersey. The second part provides a detailed assessment of parameter-specific water quality, on a stream-based scale, using monitoring results from individual locations. This provides detailed water quality condition data which underlie the overall use attainment assessments, determining whether a use is supported or not.

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Water quality assessments are completed based upon procedures outlined in the 2006 Integrated Water Quality Monitoring and Assessment Methods (Methods Document) that can be downloaded at http://www.state.nj.us/dep/wmm/sgwqt/wat/integratedlist/06MethodsDoc.pdf. In general, assessments of HUC14 subwatersheds are based upon water quality data taken from monitoring sites within the HUC14 in question. If data from within a HUC14 was insufficient or absent, data from neighboring HUC14 subwatersheds were extrapolated along contiguous waterways into HUC14s where the water quality assessments might apply. This was performed only in situations where land uses were consistent and no major tributaries or pollution sources appeared between neighboring HUC14 subwatersheds. In some cases, monitoring sites from one HUC14 formed the basis of assessments in two, three and in a few cases as many as four neighboring HUC14s. Monitoring stations that formed the basis of multiple HUC14 assessments are listed in Appendix A. The assessment of aquatic life use support in New Jersey is based on a direct evaluation of instream biological communities, specifically fin-fish and benthic macroinvertebrate (insects, worms, clams etc.) communities, whenever possible. Such biological monitoring is based on the premise that biological communities are shaped by the long-term conditions of their environment and best reflect the health of an ecosystem. Benthic macroinvertebrate assemblages are generally reflective of short- term and localized impairment. Currently, the NJDEP monitors benthic macroinvertebrate assemblages at numerous stream stations in the Highlands Region. In order to assess environmental conditions on a larger spatial and temporal scale, in 2000 the NJDEP began to supplement benthic macroinvertebrate monitoring with an index of biotic integrity (IBI). IBI measures the health of a stream based on multiple attributes of the resident fish assemblage.

The assessment methodology applied to these data is explained in the NJDEP Methods Document cited previously. All fin-fish assessments in the Highlands Region were assessed in the 2006 Integrated Report as being Excellent, Good, or Fair, all categories representing full support of the Aquatic Life Use from a regulatory perspective. One exception was an IBI site in the Musconetcong River (site FIBI061) where the community was assessed as “poor.” This result reflected sampling error and more recent sampling, using improved methods, has resulted in assessing the site as acceptable. Fish IBI monitoring and benthic macroinvertebrate sites located in the Highlands Region are illustrated in the NJDEP map for Fish IBI Stations in the New Jersey Highlands, and in the

Fish IBI Stations in the