Stormwater Management: Passaic River Watershed - Term Paper Example

Passaic River Watershed Management Project Schools Number and of November 30, Table of Contents Watershed and Stormwater Management 3 Environmental Concerns 4 Possible Solutions 5 Importance of Watershed Management 5 Passaic River Basin (New Jersey, NJ) – 6 Watershed Management Project (PRBWMP) 6 The Need for Watershed Management in New Jersey 7 Watershed Management Areas in the New Jersey Passaic River Basin 7 Phase I 8 Aims and Purpose of the PRBWMP 8 Major Tasks of the Project 9 Results of Phase 1 of the Project 9 Phase II 10 Watershed Management Practices and Strategies 10 Appendix 15 References 22 Passaic River Watershed Management Project Water is an indispensable requirement for the sustenance of life, and yet, water is the most highly exploited and polluted natural resource. Concerns over the availability of potable and safe drinking water have led to the mushrooming of environmental protection programs and approaches all over the world. Using a combination of principles from hydrology, ecology, geology, and chemistry among many others, environmental engineers and policy makers have geared up to meet the needs of the hour. Stormwater and watershed management systems have been devised to protect the world’s natural water resources and to restore them to their original state. This paper discusses the Passaic River Basin (New Jersey, NJ) Watershed Management Project (PRBWMP) in detail, along with identifying and defining its goals and achievements. The paper also introduces the concept of watershed management from an environmental perspective, beginning with the basic definitions to the importance of stormwater and watershed management. The results of the assessments and characterization studies of the three watershed management areas encompassed by the PRBWMP are also discussed in detail. This paper concludes with a brief description of the Watershed Management practices and strategies suggested by the project. This paper aims to educate the importance of watershed and stormwater management, along with a detailed description of how it can be approached, using the Passaic River Basin Watershed Management Project as a case in point. Watershed and Stormwater Management A watershed is a land area that drains all its streams and rainfall into a common water body such as a lake, river, reservoir, bay or stream (NJDEP, 2010; Watt, 2000). A watershed is separated from other land entities by high areas such as hills, slopes and ridges, called as drainage divides. A watershed comprises of surface water that includes streams, lakes, wetlands, reservoirs, etc, along with the entire ground water of the region (McCann, 1992 cited in Watt, 2000). A watershed not only refers to the waterways of a region but also the complete land area draining into a water body (NJDEP, 2010). Stormwater is the water that results from precipitation events such as rainfall (Wanielista & Yousef, 1993). Some of the stormwater may soak into the ground while the remaining becomes surface runoff and drains into waterways or into storm sewers that eventually end up in surface waters. Environmental Concerns Watershed and stormwater have become great environmental concerns to such an extent that countries around the world have been forced to develop watershed and stormwater management systems. The actual concern is not the watershed or the stormwater itself but the environmental pollution resulting from human activities that is causing pollution of watersheds. Stormwater runoff from a watershed area carries with it pollutants and chemicals that ultimately reach the water body the watershed drains into. Therefore, stormwater runoff is the most widespread means through which nonpoint source pollution of a watershed area reaches streams, reservoirs, rivers and lakes (NJDEP, 2010). One way through which humans have influenced watersheds is through manipulation of stormwater flow by changing land contours. In addition, pollutants that are picked up by stormwater runoff on its way to the main water body results in contamination of watersheds. For instance, stormwater runoff from a farm or a suburban lawn picks up fertilizers and pesticides, carrying them into a lake or a pond (NJDEP, 2010). Studies have shown that rivers and lakes have accumulated so many pollutants and contaminants over the years that they are not only harmful for fishes and other living organisms in the water bodies, but also to humans who consume processed water taken from polluted water bodies. Studies by Skinner (2011) have shown that toxic chemical contaminants such as polychlorinated and polybrominated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs and PBDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) accrued in the Hudson River have now accumulated up to toxic concentrations in the resident fishes. Finley et al. (1997) have shown that the total PCBs in fishes and other aquatic biota in the lower Passaic River exceeded the benchmark levels set by the National Oceanic and Atmospheric Administration (NOAA). Pollution is not the only cause of concern for watersheds and water bodies. Another major threat is increasing urbanization. Urbanization results in large-scale constructions of concrete buildings, impervious surfaces like roads, parking lots, rooftops, etc that prevent stormwater from entering/soaking into the ground. This leads to a depression in ground water levels that further lead to stress in downstream environments (NJDEP, 2010). This also results in an increase in the rate of stormwater runoff that reaches the waterway faster than usual. This erodes stream banks and scours channels, ultimately degrading aquatic life that thrives in clear waters (NJDEP, 2010). Stormwater runoff from urban lands also affects surface sediments in rivers and lakes. Possible Solutions To reduce stormwater pollution and watershed degradation, it is essential to apply concepts and knowledge related to hydrologic, biological, chemical, hydraulic and environmental principles to devise ways in which these can be prevented (Wanielista & Yousef, 1993). Environmental engineering thus combines all these principles including those of human-environment interactions to design and operate possible solutions to environmental problems. With the help of environmental engineering concepts, watershed and stormwater management systems have been created and implemented worldwide. Watershed management involves the restoration of a watershed to a desired level (Randhir, 2007). Watershed management aims at restoring the structural and functional aspects of a watershed as close as possible to its historic conditions (Randhir). It involves programs and strategies that influence activities and the land characteristics of a watershed, by integrating land and water resources, and restoring links between upstream and downstream land and water use (CGER, 2000; Darghouth et al., 2008). Darghouth et al. (2008) describe watershed management as the integrated use of water, land and vegetation in a “geographically discrete drainage area” with the motive of protection and conservation of the hydrologic services provided by the watershed and for reducing negative influences on groundwater (p. XI). Watershed management can be achieved by reducing the amount of impervious surfaces, by reducing nonpoint pollution sources, by managing stormwater flow and through appropriate landscaping strategies (NJDEP, 2010). Importance of Watershed Management Watershed management is important for the maintenance of the chemical, biological and physical integrity of a nation’s waters, and to ensure the safety of drinking water (CGER, 2000). For the protection of source water, i.e. drinking water supply of an area, watershed management is an indispensable requirement. Moreover, watershed management ensures a steady maintenance of groundwater apart from ensuring the cleanliness and safety of a water body for its aquatic biota. Passaic River Basin (New Jersey, NJ) – Watershed Management Project (PRBWMP) The Passaic River in the US is ninety-nine miles long and the Passaic River watershed provides drinking water to over 800,000 people (Lurie & Mappen, 2004). The Passaic River Basin (NJ) Watershed Management Project (PRBWMP) was launched on 30th October, 2000, by the New Jersey Department of Environmental Protection in contract with the North Jersey District Water Supply Commission (NJDWSC, 2010). This project was initiated to enable watershed management, characterization and assessment studies in the Passaic River Basin comprising of Watershed Management Areas WMA 3, WMA 4 and WMA 6 (NJDWSC, 2010). These three WMAs are among the 20 different WMAs recognized by the NJDEP for watershed management. WMA 3, 4 and 6 are located in the non-tidal Passaic River Watershed and are collectively called the Passaic River Basin (Obropta, n.d.; NJDWSC). The Passaic River Basin is located in northern NJ and supplies drinking water to over 3 million people in the area. Moreover, it provides wildlife habitat and recreational opportunities. The basin extents across 8 counties (Bergen, Hudson, Passaic, Essex, Somerset, Morris, Union and Sussex) and 120 communities, and covers an area of over 900 square miles, terminating at the Newark Bay (NJDWSC). The major waterways comprising the Watershed Management Area WMA 3 include Wanaque River, Ramapo River, Pompton River and Pequannock River. The WMA 4 includes the Saddle River and the Lower Passaic River while the WMA 6 includes Whippany River, Rockaway River and Upper Passaic River. The areas comprising the three WMAs are illustrated in Figure 1. The aim of the Passaic River Basin Watershed Management Project (PRBWMP) was to assess and characterize the three WMAs in the region. The findings of these assessments revealed that the quality standards of the surface water regarding the dissolved oxygen, pH, nutrients, temperature, pesticides, pathogens and metals exceed allowable limits (Obropta, n.d.). Therefore, the water resources of these watersheds are impaired. According to these assessments, nineteen point sources of wastewater treatment in the region discharge more than 1.0 million gallons of treated effluent per day in these WMAs, resulting in a very high phosphorous load. The Passaic River Basin Watershed Management Project (PRBWMP) and the findings of its assessments have been summarized in the following sections. The Need for Watershed Management in New Jersey NJ is the most highly populated state in the US and the population is expected to increase by a million by 2020 (NJDWSC, 2010). Surface water supplies are limited and the current reservoirs for drinking water are at risk of depletion. Therefore, there is an urgent need for protection and quality restoration of the state’s waters (NJDWSC). Thus, the development of an efficient and successful watershed management plan is an essential step in that direction. The New Jersey Department of Environmental Protection identified three priority areas for management concerns for which mere regulatory programs are not enough. These three key concerns include non-point source pollution, land use and water withdrawal. These issues can be addressed through carefully planned and strategized watershed management approaches. Such an approach entails a “coordinating framework” that not only protects and restores the aquatic ecosystems but also eliminates any ensuing dangers to human health. Most of the pollution and quality issues of a water body are best examined through watershed evaluation rather than evaluation of the water body alone. Watershed management is necessary to ensure that the waterways meet the requirements of the Clean Water Act (CWA) and the Safe Drinking Water Act (SDWA) to ensure clean and potable drinking water (CGER, 2000). Watershed Management Areas in the New Jersey Passaic River Basin Watershed management area 3 (WMA 3). This watershed region covers 238 square miles of New Jersey along with an additional 140 square miles of New York. It has nine surface water reservoirs and includes the watershed lands of Newark. Furthermore, it comprises the Wanaque and Monksville Reservoirs that are main sources of drinking water. A map of the area is provided in Figure 2. Watershed management area 4 (WMA 4). This watershed area covers 188 square miles of New Jersey along with an additional 8 square miles of New York. It also includes the Great falls of Paterson, and covers five counties with 66 municipalities. A map of the area is provided in Figure 3. Watershed management area 6 (WMA 6). This watershed area covers 361 miles in New Jersey and has seven reservoirs and three NJ American Water Company reservoirs. It covers five counties with 52 municipalities. A map of the area is provided in Figure 4. Interrelationships between the three WMAs – need for a coordinated approach. The three watershed areas of the Passaic River Basin are highly interrelated from the perspective of natural river flow and also from the perspective of water supply infrastructure. The natural flow of the rivers is from WMA 3 to the lower reaches of WMA 6 from where it flows into WMA 4. Therefore, the quality of water in the WMA 4 is affected by that in WMA 6, which is itself affected by WMA 3. Because of the interrelationship between these three watersheds, an integrated and well-coordinated approach is required for successful watershed management in these three areas (NJDWSC, 2010). Phase I The following sections summarize information provided by the assessments and characterization studies conducted in phase 1 of the Passaic River Basin Watershed Management Project, as provided by the North Jersey District Water Supply Commission (NJDWSC, 2010). Aims and Purpose of the PRBWMP The aim of this watershed management project is to assess and characterize the three watershed areas and identify issues and concerns, followed by appropriate watershed management strategies and planning for restoring and maintaining the water quality and quantity, apart from maintaining the health of the aquatic ecosystems in these watersheds and the accompanying waterways. It aims to provide plentiful water for the present and ensure plentiful water for the future for drinking, fishing and swimming purposes. The project aims at educating people about the importance of watershed management, remediating nonpoint source pollution, preserving open land areas, restoring the recreational value of the Passaic, involving stakeholders, improving quality and availability of water, collaborating with all parties including NGOs, Governments and citizens, managing storm water, raising groundwater levels, increasing access to the river, wastewater effluent recycling, and watershed maintenance and improvement. Major Tasks of the Project The technical aspects of the project include four technical tasks described below: To identify watershed stressors in WMAs 3, 4 & 6. This task included the detailed assessment of natural resources such as surface and groundwater of the three WMAs along with a detailed description of water availability, demographics and recreational applications. Land use and land cover were also assessed. Potential sources of contamination were identified and water quality was characterized. To acquire GIS maps of WMAs 3, 4 & 6. This task included the creation of Geographical Information System (GIS) maps of the three WMAs showing detailed characteristics of the natural resources, watershed limits, land use, transportation networks, surface and groundwater locations, contamination source locations, demographic information, surface water impairments, and monitoring stations. Limnological Consulting. This task involved discussions on endpoints and water quality goals apart from a detailed study of the waterways. Project Oversight. This task comprised of general consulting and co-ordination of the teams for the preparation of progress reports. Results of Phase 1 of the Project Topography and physical geography of WMA 3, WMA 4 and WMA 6. The topography of all the three regions is varied. The elevations in WMA 3 extend from the Passaic and Pompton river confluence at 160 feet above sea level to the ridges and plateaus in the Highlands at 1350 feet above sea level. The portion in the Newark Basin is low lying and occasionally exceeds 680 feet elevation above sea level along the crests of the ridges. The majority of the land is 200-400 feet above sea level. The relief and major landforms of WMA 3 are shown in Figure 5. The elevations in WMA 4 extend from sea level to over 850 feet at some places along the Watchung Mountains. The majority of the land is 50-300 feet above sea level. The relief and major landforms of WMA 4 are shown in Figure 6. The majority of land in WMA 6 ranges between 150-250 feet above sea level. The majority of the land is 50-300 feet above sea level. The relief and major landforms of WMA 6 are shown in Figure 7. Land use and contamination sources. The modern land use as of 1995 in WMA 3, 4, and 6 is shown in Tables 1, 2, and 3, respectively. As is evident from the tables, forested areas are the largest land use category in WMA 3, while urban use is the largest land use category in WMA 4 and WMA 6. Urban land use includes industrial, commercial and residential uses. The forestlands are estimated to decrease at a steady rate by 2020. The projected figures for forest areas in the upcoming years for all three WMAs are shown in Tables 4, 5 and 6. Potential sources of contamination in all these areas include both point and non-point sources. These include surface runoff, erosion and sediment, landfills, commercial sources such as golf courses, industrial, residential and agricultural sources. Phase II The following sections summarize the Watershed Management planning strategies that comprise phase 2 of the Passaic River Basin Watershed Management Project, as provided by the North Jersey District Water Supply Commission (NJDWSC, 2010). Watershed Management Practices and Strategies Apart from determining the major issues and concerns of the three watershed areas as phase I of the Passaic River Basin Watershed Management Project, the second phase aimed at recommending and identifying watershed management strategies. These are discussed as follows: The watershed characterization phase of the project involved the development of a web-based GIS system for use in future tasks for integrating data and information that would be helpful in generating a watershed management plan. As part of this phase, Killam Associates retained Ecosystem Consulting Service, Inc. (ECS) for providing a limnological review and consultation for the identification of endpoints and alternative management strategies. The limnological review recommendations were based on the aquatic ecosystem existing in the WMAs. The limnological perspectives were included to help in the identification of the needs of the various aquatic ecosystems so as to restore or preserve these ecosystems. Water conservation. The demand for water has increased significantly in NJ as a result of increased needs, both residentially and commercially. The natural reservoirs have not been able to meet the increasing demands. If river waters have to be diverted to storage reservoirs, huge amounts of energy are expended and it also results in an alteration of stream flow, apart from resulting in a reduction of the stream flow’s dilution/assimilative capacity. As part of a watershed management strategy, water conservation is a high priority concern. Plumbing code changes, low water demand landscaping, low volume fixture, and leak detection and repair are some of the water conservation techniques developed in the US. Treatment of wastewater from point source discharges. Another effective watershed management strategy would involve remediation of wastewater. Discharges from wastewater treatment plants are major loading sources of nitrates, ammonia, TP, oxygen demand, organics, etc in streams. These loadings from discharge are a major concern especially during droughts or under low flow conditions as the natural runoff during these times is low, and so the dilution rate is low. The main problem arises when these pollutants accumulate in reservoirs. The loading rates of ammonia to streams have to be controlled so that potential toxicity can be avoided. Increased ammonia results in oxygen depletions as ammonia is nitrified to nitrates. Aeration and nitrification done during wastewater treatment can help in the prevention of ammonia loading in streams and reservoirs. Aerobic nitrification when coupled with anaerobic denitrification is useful in removal of nitrogen from discharge. Another potentially useful strategy for management of wastewater discharge is the optimization and upgrading of wastewater treatment plants. These plants should be optimized for removal of phosphorous and nitrogen before discharging effluent. Many plants have applied enhanced coagulation techniques to remove organic matter. Well-designed systems can be implemented in wastewater treatment plants to remove point source pollutants prior to discharge. Another effective management strategy would be to design leaching fields so as to maximize the volume of soil contact prior to the septic plume dumped at an exfiltration site. Stormwater management. This will have to be implemented to prevent or nullify the nonpoint pollution loading from stormwater runoff especially occurring in agricultural areas in high coverage impervious surfaces. The stormwater management applied in a watershed area should mimic the area’s natural hydrograph, which includes peak runoff, time of concentration, duration of runoff and base flow. Ordinarily, runoff is collected by a drainage system and transported to the location of discharge. However, a better proposition is to dispose the runoff as close as possible to its place of origin. For instance, runoff from a place can be directed to low lying areas in its vicinity, especially those areas that are well vegetated or wooded, allowing it to seep into the ground. Retention of natural wooded areas is essential and large lawn areas or ornamental landscaping that simulates closed canopy woodlands can help in the restoration of infiltration rates, reduction of peak runoff, improvement in runoff quality and sustenance of adequate stream baseflow. “Landscaped simulated woodlands” containing loose and permeable soils, partial shrub and tree covers, etc can mimic the hydrologic functions of woodlands. (NJDWSC, 2010, p. 8.2-3). Structures such as infiltration basins, offline detention basins that are designed to accommodate first flush volume and filtration systems that trap particles or absorb pollutants are good strategies for stormwater management, especially in commercial and industrial areas. Another efficient strategy would be to set aside vegetation areas for retaining stormwater, increasing infiltration, and removing pollutants. These vegetation areas can be established as riparian buffers, vegetated swales or filter strips, depressed road center strips, rain gardens, parking lot islands etc. In-stream management. Other approaches for improving water quality include management methods for streams. The restoration of floodplains and riparian areas associated with streams can help in restoring the interconnections between adjacent floodplains, wetlands and streams. Streambeds can be reconfigured by excavating new channels for shallow or extremely braided streams. The natural meandering patterns can also be restored to their original hydrologic conditions. Stabilization of stream banks can be achieved with the help of branch packings and brush mattresses among other things. These can be selected based on the type of soil, slope of the bank and the corresponding hydrologic conditions. Wing walls (channel constrictors and deflectors) can be applied to narrow down or deepen streams for increasing the effective discharge, encouraging meandering, and for protection against erosion of banks. Boulder clusters can be installed for increasing structural complexity and for creating eddies. Low drop structures can also be created for enabling pool formation and stimulating turbulent flow. Using a combination of all these approaches can help in enhancement of the rates of aeration in low gradient and high-order streams that are susceptible to diurnal variability or suffer from low dissolved oxygen. Methods for supply diversion. Managing the diversion of water to a water treatment plant or to a reservoir can influence water quality. It is important to construct water supply intakes upstream of the wastewater treatment plant discharge points. This is however difficult to accomplish in the Passaic River Basin. Some of the supply diversion options include seasonal or flow stage selection, direct use of withdrawn water, use of in-stream structures such as inflatable weirs, etc. In-lake/In-reservoir management systems. These systems aim at avoiding degradation of habitat and for increasing the capacity of a water body to intake nutrient and contaminant loads without affecting its quality. These may include operational methods such as source sequencing, depth selective withdrawal, outflow and seasonal drawdown apart from chemical treatment methods that include using algaecides and herbicides for controlling plankton and aquatic mycrophytes, and through nutrient inactivation. Infrastructural methods. Retrofit attachments can be made in distribution reservoirs that have a narrow depth-selective withdrawal range. Retrofit attachments include telescopic towers, weirs, etc. Discharge control assemblies can be incorporated in lakes and reservoirs to enable water to leave at a certain depth. This does not require additional implements such as siphoning, pumping or deep release gates. In lakes and reservoirs, longitudinal reaches can be isolated with the help of submerged weir curtains or thermal partitions to enable the containment of highly productive zones and to prevent lake-wide impacts. Mechanical methods. Mechanical methods include aeration and stratification management, artificial circulation, depth discrete layer aeration, hypolimnetic aeration, integrated depth discrete aeration, macrophyte harvesting, nutrient inactivation and area dredging. These methods enable enhancement of water quality and protection of aquatic habitat. Biological methods. Other methods for improving water quality include ecological and biological methods. These methods aim to balance the food web by improving biological processing of the biomass. The biological methods enable the acceleration of secondary productivity keeping the primary productivity at a constant level. Such methods include biomanipulation of the trophic levels through the maintenance of a “healthy population of herbivorous zooplankton” (p. 8.2-10). Incorporation of macrophyte grazers is another beneficial approach. Biological methods have been successful in efficient lake management to a certain extent. Area specific concerns. Loading assessment results indicate that much of the Pompton, Ramapo, Passaic, Saddle, Whippany and Rockaway rivers are heavily contaminated with effluent, and have a high load of total and dissolved phosphorus and total nitrogen along with nitrates. Point source discharge contributes 71% of TP, 58% of ammonia nitrogen, and 67% nitrate loads in WMA 3, 89% of TP, 59% of the ammonia-N, and 81% nitrate loads in WMA 4 and 91% of TP, 52% of the ammonia-N, and 79% nitrate loads in WMA 6 (NJDWSC, 2010). Improvement of wastewater treatment, stormwater management and improvement in riverine ecosystems apart from controlling nonpoint pollution sources will thus be important concerns in the wastewater management project at WMAs 3, 4 and 6. The Passaic River Basin Watershed Management Project will enable the restoration and maintenance of the three watershed areas – WMAs 3, 4 and 6. It would enable an increase and maintenance of groundwater levels, and will help in the maintenance of stream base flows. The quality of surface and ground water will be restored and maintained up to the best standards with minimal pollution. The existing nitrogen and phosphorus loads of the Passaic River will be lowered and it will become accessible for recreational and potable purposes. Through stormwater management, it will be possible to maintain stormwater volumes and peak flows. It would promote a balance between land use and hydrological restoration. The river’s ecosystem and aquatic biota will also be restored. The project has a variety of stakeholders working together in a coordinated and well-integrated approach towards the efficient management of the three watershed management areas of the Passaic River Basin. Appendix Figure 1 WMA 3, 4, 5(NJDWSC, 2010). Figure 2 WMA 3(NJDWSC, 2010). Figure 3 WMA 4 (NJDWSC, 2010). Figure 4 WMA 6 (NJDWSC, 2010). Figure 5 (NJDWSC, 2010). Figure 6 (NJDWSC, 2010). Figure 7(NJDWSC, 2010). Table 1 (NJDWSC, 2010). Table 2 (NJDWSC, 2010). Table 3 (NJDWSC, 2010). Table 4 (NJDWSC, 2010). Table 5 (NJDWSC, 2010). Table 6 (NJDWSC, 2010). References CGER. (2000). Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, D.C.: National Academy Press. Retrieved 30 November, 2011 from http://www.nap.edu/openbook.php?record_id=9677&page=R1 Darghouth, S., Ward, C., Gambarelli, C., Styger, E., & Roux, J. 2008. Watershed Management Approaches, Policies, and Operations: Lessons for Scaling Up. Washington, D.C.: The World Bank. Retrieved 30 November, 2011 from http://siteresources.worldbank.org/TURKEYEXTN/Resources/361711-1216301653427/5218036-1267432900822/WatershedExperience-en.pdf Finley, B. L., Trowbridge, K. R., Burton, S., Proctor, D. M., Panko, J. M., & Paustenbach, D. J. (1997). Preliminary assessments of PCB risks to human and ecological health in the lower Passaic River. Journal of Toxicology and Environmental Health, 52(2), 95-118. Retrieved 30 November, 2011 from http://www.tandfonline.com/doi/abs/10.1080/00984109708984055 Lurie, M. N., & Mappen, M (eds.). (2004). Encyclopedia of New Jersey. Piscataway, NJ: Rutgers University Press. Retrieved 30 November, 2011 from http://google.books.com NJDEP. (2010). Basic Information. Retrieved 30 November, 2011 from http://www.nj.gov NJDWSC. (2010). Passaic River basin – Watershed Management Program. Retrieved 30 November, 2011 from http://www.njdwsc.com Obropta, C. C. (n.d.). Development, Implementation, and Evaluation of a Water Quality Trading Program for the Non-Tidal Passaic River Watershed. Retrieved 30 November, 2011 from http://www.epa.gov/owow/watershed/initiative/2004/2004proposals/04passaic.pdf Randhir, T. O. (2007). Watershed management: issues and approaches. London, SW: IWA Publishing. Retrieved 30 November, 2011 from http://google.books.com Skinner, L. C. (2011. Distributions of polyhalogenated compounds in Hudson River (New York, USA) fish in relation to human uses along the river. Environmental Pollution, 159(10), 2565-2574. Retrieved 30 November, 2011 from http://www.sciencedirect.com/science/article/pii/S026974911100340X Wanielista, M. P., Yousef, Y. A. (1993). Stormwater management. New York: John Wiley & Sons. Retrieved 30 November, 2011 from http://google.books.com Watt, M. K. (2000). A Hydrologic Primer for New Jersey Watershed Management. U.S. Geological Survey, Water-Resources Investigation Report 00-4140. West Trenton, NJ: U.S. Geological Survey. Retrieved 30 November, 2011 from http://nj.usgs.gov/publications/WRIR/00-4140/wrir00-4140np.pdf Read More