As a mature suburb, Upper Southampton Township is largely built out. However, many diverse natural resources remain that should be properly managed by ecologically sound approaches for the benefit of future generations. Having an understanding of the natural resources of the township is crucial for making decisions concerning all land use planning and development. Conservation of natural resources helps to maintain the character of a place and enhances the municipality overall. Ultimately, if natural resources are destroyed, they cannot be replaced.
Among the important natural resources that should be protected and regulated in Upper Southampton are steep slopes, woodlands, wetlands, and floodplains. Other related topics of environmental concern for an urbanized municipality such as Upper Southampton would be air quality and water quality.
The natural features of the township help to make it a desirable place to live. The 1968 Comprehensive Plan for Upper Southampton Township addressed the critical natural features. Over the years, the township has adopted zoning ordinance provisions to implement protection of many natural features. The plan's review continues to emphasize a strong protection policy of natural resources. This policy is based on the Constitution of the Commonwealth; in particular, Article 2, Section 27 which states:
The people have a right to clear air, pure water, and to the preservation of the natural, scenic, historic and aesthetic values of the environment. Pennsylvania's public natural resources are the common property of all people including generations yet to come.
The township's natural resource protection policy is also reinforced by Article VI of the Pennsylvania Municipalities Code which authorizes "provisions for the protection and preservation of natural resources and agricultural land and activities." The Municipalities Planning Code has charged local governing bodies with the responsibility of protecting the citizens' health, safety and welfare through comprehensive planning and land use ordinances. The code permits local governing bodies to regulate the use of land, watercourses, and bodies of water not only by area requirements and lot sizes, but also by the determination of densities and the location and amount of open space. In addition, Section 605(2) specifically authorizes local officials to regulate, restrict or protect land uses and structures at or near natural or artificial bodies of water, (iii) places of relatively steep slope or grade,…(vii) flood plain areas and other places having a special character or use affecting or affected by their surroundings." Through comprehensive planning the township has the power to adopt conservation goals and development guidelines which protect environmentally sensitive areas.
A high quality environment is an important goal for the township. Development without concern for the natural limitations and amenities of the land can be costly for people, as individuals and as taxpayers in the community. Development in flood plains, alluvial soils, and filling of lakes, ponds, and watercourses can result in property damage and the loss of life due to increased flooding. The overuse of steep slopes and the stripping of woodland and vegetative cover can cause undue soil erosion and excessive sedimentation in the natural drainage systems.
Through the use of various sources, the natural features have been mapped on a work map in order to analyze and determine the extent of their influence on land use planning. An analysis on a tract-by-tract basis is not appropriate for a township-wide comprehensive plan. That level of detail is required for all subdivision or land development applications. Therefore, the purpose is not to identify the extent of natural features on a tract-by-tract basis, but rather, to identify natural feature protection areas.
Upper Southampton is located mostly within the Triassic Lowland section of the Piedmont Province, an uplifted plain formed on relatively soft, red sandstone and shale. Higher ridges mark the locations of sheets of hard, dense rock or lenses of quartz conglomerate. The general level of this rolling plain is less than 400 feet above sea level. The southeastern corner of the township is located within the Piedmont Upland section of the Piedmont Province. This section contains metamorphosed igneous rock of the pre-Cambrian geologic era.
Two major subsurface geologic formations underlie the township. These are the Stockton Lithofacies of the Triassic Lowland section of the Gneiss of the Piedmont Upland section. The Stockton formation, one of the best groundwater sources in the country, covers more than three quarters of Upper Southampton. However, today, most of the township is dependent upon public water supply, rather than upon private well water.
A unique underlying dike of metadiabase borders on the lower eastern edge of the township. This dike is about 300 feet thick and extends 1.4 miles in Bucks County. Southward, it continues approximately an equal distance into Montgomery County; to the northeast it is overlain by the Stockton lithofacies. The metadiabase dike was injected into a fracture in the gneiss along the Cream Valley-Huntingdon Valley fault and was subsequently metamorphosed.
Surface characteristics in Upper Southampton range from a topography that is nearly level to gently sloping in valleys, and to sloping on ridges. The areas of steep slopes are those areas where the average slope is greater than 8 percent. Slopes of 8 to 15 percent grades are moderate slopes and construction activity will produce moderate rates of erosion and sediment loading if not controlled. For slopes in the 8 to 15 percent range, construction employing proper engineering methods is safely possible. However, those areas of steeper slopes should be considered as sites more suitable for development which would disturb less soil and leave more land open and undisturbed.
Slopes of 15 to 25 percent grades are considered steep and disturbed areas will yield heavy sediment loads, while very steep slopes over 25 percent grade produce heavy erosion and sediment loading areas to be kept in at least 80 percent undisturbed open space. Loss of woodlands could impact other environmentally sensitive areas. For Upper Southampton, this would be of importance particularly, along, the township's stream valleys, where some of the land is steeply sloped, or else is flood prone.
According to the Bucks County Natural Resources Plan, for development sites not located on environmentally sensitive or other designated preservation areas, woodland protection standards may be more flexible. On those sites, 50 percent open space protection may be implemented Bucks County Natural Resources Plan, 1986, p. 19).
Street trees are another element related to woodland resources in urbanized areas. Trees planted along streets and in parks are valued for aesthetic and recreational purposes. Furthermore, they screen out noise and aid in pollution abatement. The township has acknowledged the importance of street trees with a subdivision and land development ordinance requirement for street tree planting within any land development or subdivision where suitable trees do not exist. The township also has formed a shade tree commission that reviews plans of proposed street tree planting. In addition, the historic tracts of land that compose Tamanend Park, where a nursery once stood, contain many rare specimen trees that are prized by both residents of the community and visitors to the township.
A number of spring fed ponds with cold water support a variety of fish including bass and trout. In addition, other natural and manmade ponds provide environments for resident and migrating water birds. Allowing these ponds to exist with occasional maintenance is desirable.
The National Wetlands Inventory Map shows that individual wetland areas which are larger than two acres in size exist throughout Upper Southampton Township, except in the northwestern quadrant. Where it is deemed necessary by the board of supervisors, wetlands are delineated through field surveys by professionals such as hydrologists and soil scientists, who determine their existence by analyzing vegetation, soils, and hydrology. The township requires wetland delineations to be validated by the Pennsylvania Department of Environmental Resources and the U.S. Army Corps of Engineers.
Typically, wetlands occur as marshes, swamps, and bogs. Often, they are saturated lands or areas that display a seasonal high water table. Some of the wetland areas in Upper Southampton Township are along creeks or coincide with streams, creeks, and ponds. Even in built out and urbanized areas, wetlands are important. They help to improve water quality by filtering toxins. In addition wetlands assist with groundwater recharge. Wetland areas act as natural retention basins for stormwater. After a storm, the slow release of the water helps to reduce the amount of flooding for the surrounding areas.
The township's zoning ordinance requires 100 percent protection of wetlands. Furthermore, any encroachment for approved dedicated roadways must have permits from the Pennsylvania Department of Environmental Resources and the U.S. Army Corps of Engineers. The township zoning ordinance also requires a wetland margin as a transitional area extending from the delineated wetland boundary. Only limited intrusion into wetland margins is permissible.
Both Southampton Creek and Mill Creek flow through the township. Southampton Creek has a total drainage area of 5.8 square miles at its confluence with Pennypack Creek outside of the township. Mill Creek has a total drainage area of 17.4 square miles at its confluence with Neshaminy Creek, also outside the township. These two waterways drain the entire 6.7 square mile area of the township. Southampton Creek, which is within the Pennypack watershed, drains about a third of the township. Mill Creek, which is within the Neshaminy Watershed, drains the remaining part of Upper Southampton Township.
Floodplain and Alluvial Soils
Floodplains are areas adjoining streams that accommodate floodwater. The floodplain is defined by the 100-year or base flood which has a 1 percent chance of being equaled or exceeded in a given year. The floodplain includes floodways and flood fringes.
Floodway is defined as the watercourse channel and adjacent lands reserved to carry the base flood without cumulatively increasing the base flood elevation more than a designated height. The maximum increase allowed by the National Flood Insurance Program is one foot.
The flood fringe is part of the base floodplain outside of the floodway. Under the National Flood Insurance Program (NFIP) obstructions causing any rise in the base flood elevations are prohibited. The flood fringe, on the other hand, may be developed under federal guidelines. However, structures must be elevated or flood proofed up to the base flood elevation.
Floodplain soils or alluvial soils indicate where flooding has occurred in the past. Sometimes, these soils appear in areas that have not been mapped under the National Flood Insurance Program. However, areas where alluvial soils now exist, or had existed in the past, must be considered as part of the floodplain. An enforceable buffer needs to be established for all floodplain areas as a development management device.
The current Upper Southampton Zoning Ordinance does not permit encroachment coverage in streams, rivers, watercourses, ponds, flood hazard areas, or floodplain soils. The township's Flood Hazard Area Map is based on land delineated by the Flood Insurance Study for the township of Upper Southampton as performed by the Federal Emergency Management Agency/Federal Insurance Administration (FEMA/FIA) dated 1978, and by the Interim Soil Survey Report, Volume II, prepared by the Soil Conservation Service, 1970. The flood hazard area has also been designated by the U.S. Army Corps of Engineers Study (Upper Southampton Township Zoning Ordinance, Section 1409 (2)(A). However, some older areas of the township have flooding problems because they were built in flood prone areas prior to any local regulations.
As an urban/suburban area, Upper Southampton Township's streams may exhibit unacceptable types of water quality problems that are generally associated with automobile dependent, residentially developed communities. Nonpoint source pollutants stem from urban runoff such as gasoline and motor oil on parking lots. Sidewalks, driveways, and other residential yard surfaces produce pollutants from the use of herbicides, pesticides and fertilizers. These materials flow into storm drains which in turn may affect the entire stream.
Furthermore, construction sites contribute to stream pollution by erosion and sedimentation carried in runoff and washing into storm drains. The runoff transports suspended solids and other toxins that may harm organic and aquatic life in streams. Therefore, Upper Southampton Township, like any urbanized community, must plan for water quality and remediation to address stream maintenance and stormwater collection systems. Also, there is a small portion of the municipality where residential dwellings use on-lot sewage disposal facilities. Regular maintenance of these types of facilities, (i.e. septic tank inspection and pumping) is essential to avoid contamination of streams and water tables. It is also helpful for urbanized communities to perform an environmental inventory to include mapping of significant natural features and wetlands, and institute public education programs about these areas with regard to damage from nonpoint pollutants.
Upper Southampton Township lies within the Philadelphia Consolidated Metropolitan Statistical Area (CMSA) which has been characterized as a severe non-attainment area for air quality because of unacceptable levels of ozone, carbon monoxide, and particulate matter. The region must attain an acceptable standard by 2005. Typical pollution that is experienced in the area may be attributed to regional industrial activity and motor vehicle emissions.
Subsequently, the township should address how air pollution affects public health, plant, and animal life. Although Upper Southampton Township is an automobile dependent suburb, it will be important to plan future development to reduce pollution and to improve air quality. For the future, federal legislation will require reduction in the number of commuter car trips in order to improve air quality.
The Federal Clean Air Act Amendments of 1990 (CAAA) requires states to establish Employer Trip Reduction (ETR) programs for severe non-attainment areas. Businesses that employ 100 employees or more, which are located in the Philadelphia Consolidated Metropolitan Statistical Area (CMSA), must plan an ETR program that is designated to increase Average Passenger Occupancy (APO). Employers must submit a compliance plan to Pennsylvania Department of Environmental Resources.
Upper Southampton Township contains several critical areas or tracts that may be considered environmentally sensitive to some extent, due to various ecological factors. These areas include tracts that contain one or more of the following elements: alluvial soils, wet soils, steep slopes, woodlands, and floodplains. Other related topics of environmental concern for an urbanized municipality such as Upper Southampton, are air quality and water quality.