Water Quality Monitoring and Assessment in Northern New Jersey Watershed
Lindsey K. Mirrer1 and Norman F. Pelak2
- Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, USA
- Department of Civil Engineering, University of Alabama, Tuscaloosa, AL 35486, USA
Over a century of rapid urbanization and industrialization in New Jersey brought visible ever-increasing stress on the resource and environmental capacities of the watershed. Environmental quality is a major concern in this region with the urbanization and economic development. As a 8-week long National Science Foundation (NSF)-supported Research Experience for Undergraduate Students (REU) program, this study compares the stream water quality in four Northern New Jersey watersheds with different land use types (i.e., urban, agricultural, and forested). A total of eight sites were chosen for this study with two sites for each watershed to investigate if the land use type has an effect on the water quality, and if so, what that effect is. Physical and chemical parameters, such as temperature, pH, conductivity, solids content, nitrate, and phosphate, were measured during this study as indicators of the water quality. A number of correlations between these parameters were found during the data analysis. Our preliminary results indicate that the land use change has a significant impact on the water quality, causing impaired rivers, streams, lakes and reservoirs in New Jersey watershed. The results from this study are important and useful for developing future environmental management strategies for environmental restoration and urban coastal development.
This study examines the effects of land use on the water chemistry in northern New Jersey watersheds across Sussex, Morris, Essex and Passaic Counties. All the study sites are associated with urban or agricultural land use. In this study, we found that increasing phosphorus levels in shallow stream waters were linked to the increase in farm lands use of phosphorus based fertilizers to help increase grass growth for cows (Withers et al. 2007). Runoff from impervious surfaces are the main causes in the change of river quality, and the effects of urbanization on streams are not limited to increases in temperature alone (Paul & Meyer 2001). Variations in temperature, pH, nitrate, phosphate, specific conductivity, and solids in the watersheds were observed. This information obtained from this study can be used to quantitatively assess whether or not the streams under investigation have been affected by their respective land uses (urban, urbanizing, agricultural, or forest), and if so, how they have been affected.
The filed work was carried at eight sites distributed in four different types of watershed in northwest New Jersey in summer 2012 (Fig. 1; Table 1). YSI 556 MPS was used to test for pH, temperature, and specific conductivity. Done by dipping the probe into the middle of the stream and leaving suspended in the water until readings are stable for 30 seconds. Specific conductivity was calibrated during the first day of research by making a conductivity standard of 0.01 M KCl, 1412 mS/cm, the probe was submerged into the solution and 10 minutes were needed for the readings on the YSI meter to stabilize. Dissolve oxygen meter was calibrated regularly on a weekly basis if there is no complications occurred. pH meter was calibrated during every use in the field. By using a pH buffers of 4 and 7, the YSI 556 MPS probe was placed into the specified buffer, stabilization occurred after 10 minutes, and that buffer was recorded into the YSI 556 MPS. Total and suspended solids for each site were collected in 1000 mL bottles and brought back to the lab. An aliquot of 100 mL of water sample was filtered through a fiberglass paper using a vacuum, then dried at 105°C for 24 hours. Total dissolved solids, total suspended solids and total solids were calculated by weight difference before and after drying.
Figure 1. GIS map showing the sampling stations in Northern New Jersey watersheds.
Results: Physical and chemical parameters from the field work measurement and database acquisition are graphically shown in Figs. 2 to 12. Total dissolved solid concentration in the stream water as shown in Figs. 2. Fig. 3 and 4 show spatial and temporal variations of temperature and pH at the sampling sites. Figs. 5 and 6 show comparison of specific conductivity and pH in our study area with that in Passaic River.
The amount of impervious surface in a watershed plays a major role in determining the quality of the water in its streams, and in urban or urbanizing areas. It can pose a major threat to stream health. Water quality can change with as little as 10% of a watershed being covered by an impervious surface. When 30% of land is covered by some type of impervious surface, the water quality can suffer so much that certain types of aquatic life can no longer live in a given stream (Arnold and Gibbons, 1996).
Change in rainfall between June 26th and July 3rd could have contributed to the variance in stream temperature. June 26th temperatures had a high of 73 F, with a low of 53.1 F at night, according to Weather Source. Between these two time frames the weather was between the 81.0 F and 91.9 F at it’s peak points, on July 3rd however the temperatures rose to a high of 89.1 F.
Variation between the two Rockaway sites is that site R4 had more typical urban land use immediately surrounding it than that of the R6 site, which was located in a heavily forested section of the watershed. This could contribute to the site showing less “typical” urban water chemistry attributes in all fields of interest.
Site (P5) had a TSS concentration 3 times higher than that of the next highest site. Jordan et al (1997) found a correlation between cropland and TSS in Maryland watersheds, and so it is likely that site P5 had higher TSS concentrations because of the heavy agricultural activity at that site.
- Arnold CL, Gibbons CJ. (1996) Impervious Surface Coverage: the Emergence of a Key Environmental Indicator. Journal of the American Planning Association, 62 (2): 243–258.
- Jordan T.E., Correll D.L., and Weller D.E. 1997. “Relating Nutrient Discharges from Watersheds to Land Use and Streamflow Variability.” Water Resources Research, 33(11): 2579-2590
- Paul MJ, Meyer JL. 2001. Streams in the Urban Landscape. Annu. Rev. Ecol. Syst. 32:333-65.
- Withers P, Hodgkinson R, Adamson H, Green G. (2007) The Impact Of Pasture Improvement On Phosphorus Concentrations In Soils And Streams In An Upland Catchment In Northern England. Agriculture, Ecosystems & Environment 122 (2): 220-232.