WATER RESOURCES PAGE. Groundwater

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1 WATER RESOURCES PAGE Water Resources Water resources consist of two main sources of water: surface water and groundwater. Surface water is water in a river, lake or fresh water wetland. Surface water is naturally replenished by precipitation and naturally lost through discharge to the oceans, evaporation, and sub-surface seepage. Groundwater is fresh water located in the pore space of soil and rocks in the subsurface. The natural input to groundwater is seepage from surface water. The natural outputs from groundwater are springs and seepage to the rivers and oceans. Surface Water Although the only natural input to any surface water system is precipitation within its watershed, the total quantity of water in that system at any given time is also dependent on many other factors. These factors include storage capacity in lakes, wetlands and artificial reservoirs, the permeability of the soil beneath these storage bodies, the runoff characteristics of the land in the watershed, the timing of the precipitation and local evaporation rates. All of these factors also affect the proportions of water lost. Human activities can have a large impact on these factors. Humans often increase storage capacity by constructing reservoirs and decrease it by draining wetlands. Humans often increase runoff quantities and velocities by paving areas and channelizing stream flow. The total quantity of water available at any given time is an important consideration. Some human water users have an intermittent need for water. For example, many farms require large quantities of water in the spring, and no water at all in the winter. To supply such a farm with water, a surface water system may require a large storage capacity to collect water throughout the year and release it in a short period of time. Other users have a continuous need for water, such as a power plant that requires water for cooling. To supply such a power plant with water, a surface water system only needs enough storage capacity to fill in when average stream flow is below the power plant's need. Nevertheless, over the long term the average rate of precipitation within a watershed is the upper bound for average consumption of natural surface water from that watershed. Natural surface water can be augmented by importing surface water from another watershed through a canal or pipeline. It can also be artificially augmented from any of the other sources listed here, however in practice the quantities are negligible. Humans can also cause surface water to be "lost" (i.e. become unusable) through pollution. Groundwater Groundwater can be thought of in the same terms as surface water: inputs, outputs and storage. The critical difference is that due to its slow rate of turnover, groundwater storage is generally much larger compared to inputs than it is for surface water. This difference makes it easy for humans to use groundwater unsustainably for a long time without severe consequences. Nevertheless, over the long term the average rate of seepage above a groundwater source is the upper bound for average consumption of water from that source. If the surface water source is also subject to substantial evaporation, a groundwater source may become saline. This situation can occur naturally under endorheic bodies of water, or artificially under irrigated farmland. In coastal areas, human use of a groundwater source may cause the direction of seepage to ocean to reverse which can also cause soil salinization. Humans can also cause groundwater to be "lost" (i.e. become unusable) through pollution. Humans can increase the input to a groundwater source by building reservoirs or detention ponds.

2 Water in the ground is in sections called aquifers. Rain rolls down and comes into these. Normally an aquifer is near the equilibrium in its water content. The water content of an aquifer normally depends on the grain sizes. This means that the rate of extraction may be limited by poor permeability. Source: Wikipedia, November 16, Stormwater Management New Britain Township has suggestions for residents to help manage our stormwater. We say our because the rain water that hits your roof, goes down your drain spout, and flows across your lawn into the street eventually enters our creeks. These creeks, and other natural resources, are what make New Britain Township a beautiful and desirable place to live. Stormwater entering the creeks increases turbidity and can raise the level of pollutants such as nitrogen and phosphorous which cause algal blooms, decrease oxygen content, and kill fish. Stormwater management can also increase the cost of New Britain Township maintenance, which is something we all pay for. So what can the average resident do to help manage storm water? Here are some suggestions: GROW A RAIN GARDEN. A rain garden uses native plants and landscaping to soak up rain water that flows from downspouts. Rain gardens allow 30% more water to seep into the ground than a conventional lawn. Rain gardens also filter out the common pollutants in water. Plants such as Black-Eyed Susan, Joe-pye Weed, and Mountain Laurels are some of the recommended plants for rain gardens. INSTALL A RAIN BARREL. A rain barrel collects and stores runoff from rooftops. Empty the rain barrel in-between storm events and use it to your lawn, garden, and window boxes. USE PLANTERS. Planters reduce impervious cover such as concrete sidewalks and parking lots and retain stormwater runoff. Planters offer green space in areas that don t have lawns. These are only a few suggestions. You can find more suggestions by doing some research and speaking with landscaping experts or with New Britain Township s Land Preservation and Environmental Advisory Committee (LPEAC). Source: A Homeowner s Guide to Stormwater Management, Office of Watersheds, Philadelphia Water Departement, Volume 1, January New Britain Township s Drinking Water Sources to learn more about North Penn Water Authority. to learn more about North Wales Water Authority. Riparian Buffers A riparian buffer is a vegetated area near a stream, usually forested, which helps shade and partially protect a stream from the impact of adjacent land uses. It plays a key role in increasing water quality in associated streams, river, and lakes, thus providing environmental benefits. With the decline of many aquatic ecosystems due to agricultural production, riparian buffers have become a very common conservation practice aimed at

3 increasing water quality and lessening pollution in America s water sources. New Britain Township has a riparian buffer program to help protect the streams in our area. Water quality benefits Intercepting sediments/nutrients - Key to counteract eutrophication in downstream lakes and ponds which can be detrimental to aquatic habitats because of large fish kills that occur upon large-scale eutrophication. Intercepting pesticides - Riparian buffers keep chemicals that can be harmful to aquatic life out of the water. Some pesticides can be especially harmful if they bioaccumulate in the organism, with the chemicals reaching harmful levels once they are ready for human consumption. Bank stabilization - This is important because erosion can be a major problem in agricultural regions when cut banks can take land out of production. Erosion can also lead to sedimentation and siltation of downstream lakes, ponds, and reservoirs. Siltation can greatly reduce the life span of reservoirs and the dams that create the reservoirs. Habitat benefits Provide habitat - Riparian buffers can act as crucial habitat for a large number of species, especially those who have lost habitat due to agricultural land being put into production. Increase biodiversity - By adding this vegetated area of land near a water source it becomes a prime location for species that may have left the area due to non-conservation land use to reestablish. With this re-establishment the number of native species and biodiversity in general can be increased. Buffers acting as corridors - Buffers also serve a major role in wildlife habitat. The habitat provided by the buffers also double as corridors for species that have had their habitat fragmented by various land uses. Shading water - The large trees in the first zone of the riparian buffer provide shade and therefore cooling for the water, increasing productivity and increasing habitat quality for aquatic species. Economic benefits Increase land value - Often people who purchase land for recreational use are willing to pay more if there is more wooded area located on the land. Produce profitable alternative crops - Vegetation such as Black Walnut and Hazelnut, which can be profitably harvested, can be incorporated into the riparian buffer. Increase lease fees for hunting - The increased habitat means that the land will be more soughtafter for hunting purposes. Buffer design A riparian buffer is usually split into three different zones, each having its own specific purpose for filtering runoff and interacting with the adjacent aquatic system. Buffer design is a key element in the effectiveness of the buffer. It is generally recommended that native species be chosen to plant in these three zones, with the general length of the buffer being 50 feet on each side of the stream. Zone 1 - This zone should function mainly to shade the water source and act as a bank stabilizer. The zone should include large native tree species that grow fast and can quickly act to perform these tasks. Although this is usually the smallest of the three zones and absorbs the fewest contaminants, most of the contaminants have been eliminated by Zone 2 and Zone 3. Zone 2 - Usually made up of native shrubs, this zone provides wonderful habitat for wildlife, including nesting areas for bird species. This zone also acts to slow and absorb contaminants that Zone 3 has missed. The zone is an important transition between grassland and forest. Zone 3 - This zone is important as the first line of defense against contaminants. It consists mostly of native grasses and serves primarily to slow water runoff and begin to absorb contaminants before they reach the

4 other zones. Although these grass strips should be one of the widest zones, they are also the easiest to install. Streambed zone - The streambed zone of the riparian area is linked closely to Zone 1. Zone 1 provides fallen limbs, trees, and tree roots that in turn slow water flow, reducing erosional processes associated with increased water flow and flooding. This also increases habitat and cover for various aquatic species Surface Water Pollution Point sources of surface water pollution include: industrial facilities (including manufacturing, mining, oil and gas extraction, and service industries) municipal governments and other government facilities (such as military bases), and some agricultural facilities, such as animal feedlots. The 1972 Federal Clean Water Act (CWA) introduced a permit system for regulating point sources of pollution. Point sources may not discharge pollutants to surface waters without a permit from the National Pollutant Discharge Elimination System (NPDES). This system is managed by the United States Environmental Protection Agency (EPA) in partnership with state environmental agencies. EPA has authorized 45 states to issue permits directly to the discharging facilities. In the remaining states and territories, the permits are issued by an EPA regional office. In previous legislation, Congress had authorized states to develop water quality standards, which would limit discharges from facilities based on the characteristics of individual water bodies. However, these standards were only to be developed for interstate waters, and the science to support this process (i.e. data, methodology) was in the early stages of development. This system was not effective and there was no permit system in place to enforce the requirements. In the 1972 CWA Congress added the permit system and a requirement for technology-based effluent limitations. Congress exempted some water pollution sources from the point source definition in the 1972 CWA, and was unclear on the status of some other sources. These sources were therefore considered to be nonpoint sources that were not subject to the permit program. Agricultural stormwater discharges and irrigation return flows were specifically exempted from permit requirements. Congress, however, provided support for research programs at the U.S. Department of Agriculture to improve runoff management practices on farms. Stormwater runoff from industrial sources, municipal storm drains, and other sources were not specifically addressed in the 1972 law. EPA declined to include urban and industrial stormwater discharges in the NPDES program and consequently was sued by an environmental group. The courts ruled that stormwater discharges must be covered by the permit program. A growing body of research during the late 1970s and 1980's indicated that stormwater runoff was a significant cause of water quality impairment in many parts of the U.S. In the early 1980s EPA conducted the Nationwide Urban Runoff Program (NURP) to document the extent of the urban stormwater problem. The agency began to develop regulations for stormwater permit coverage, but encountered resistance from industry and municipalities, and there were additional rounds of litigation. In the Water Quality Act of 1987 (1987 WQA) Congress responded to the stormwater problem by requiring that industrial stormwater dischargers and municipal separate storm sewer systems (often called "MS4") obtain NPDES permits, by specific deadlines. The permit exemption for agricultural discharges continued,

5 but Congress created a nonpoint source pollution demonstration grant program at EPA to expand the research and development of nonpoint controls and management practices. Water quality standards (WQS) are risk-based (also called hazard-based) requirements which set sitespecific allowable pollutant levels for individual water bodies, such as rivers, lakes, streams and wetlands. States set WQS by designating uses for the water body (e.g., recreation, water supply, aquatic life, agriculture) and applying water quality criteria (numeric pollutant concentrations and narrative requirements) to protect the designated uses. An antidegradation policy is also issued by each state to maintain and protect existing uses and high quality waters. Water bodies that are repeatedly out of compliance with the applicable water quality standards are subject to a Total Maximum Daily Load. A Total Maximum Daily Load (TMDL), is a calculation of the maximum amount of a pollutant that a water body can receive and still meet WQS. The TMDL is determined after study of the specific properties of the water body and the pollutant sources that contribute to the noncompliant status. Once the TMDL assessment is completed and the maximum pollutant loading capacity defined, an implementation plan is developed that outlines the measures needed to reduce pollutant loading to the non-compliant water body, and bring it into compliance. Over 60,000 TMDLs are proposed or in development for U.S. waters in the next decade and a half. Following the issuance of a water quality standard or TMDL for a water body, implementation of the requirements involves modification to NPDES permits for facilities discharging to the water body (see Title IV). While the effluent guidelines have been largely successful, because they apply to specific sources and are enforceable, the WQS have been much less so. As of 2007, approximately half of the rivers, lakes, and bays under EPA oversight were not safe enough for fishing and swimming. Helpful Links: Pennsylvania Department of Environmental Protection website Drinking water standards Click on Water Topics Water Conservation Tips Click on Water Topics