V. Environment Subregion 5 contains environmental assets of county and state importance, especially the Mattawoman Creek Watershed. The primary environmental issues that are addressed in this chapter are: protection of the Mattawoman Creek watershed, connectivity of the green infrastructure network, and water quality. The purpose of this chapter is to describe the current state of the environment in the subregion and to develop goals, policies, and strategies to protect the subregion’s environmental integrity. This chapter covers green infrastructure, water quality, the Mattawoman Creek watershed, the Chesapeake Bay Critical Area, air quality, green building, and noise intrusion. Policies and strategies are provided throughout this chapter in order to reach the following goals: Goals • The natural environment and its associated ecological functions are preserved, enhanced, and restored as a fundamental component of sustainable development. • A development pattern that complements the natural systems, incorporating open space and green infrastructure connectivity into growth strategies. A. Green Infrastructure The 2005 Approved Countywide Green Infrastructure Plan is a comprehensive vision for conserving significant environmental ecosystems in Prince George’s County. Green infrastructure is an interconnected system of public and private lands that contain significant areas of woodlands, wetlands, wildlife habitat, and other sensitive areas that provide valuable ecological functions and incur minimal intrusions from land development, light, and noise pollution. The network is divided into three categories: countywide and locally significant regulated areas, evaluation areas, and network gaps1. (Map II-6, Green Infrastructure, page 17). The Green Infrastructure Plan states that the network boundaries should be refined during the master plan process to reflect areas of local significance and that additional opportunities for connectivity and resource protection should be considered. This master plan identifies three primary and three secondary corridors that are within the green infrastructure network (Map V-1, Environmental Corridors and Special Conservation Areasm, page 70). Primary corridors are Mattawoman Creek, Tinkers Creek, and Piscataway Creek. Secondary corridors are larger tributaries to the primary corridors: Burch Branch, Butler Branch and Timothy Branch. 1 Regulated areas are environmentally sensitive features (streams, wetlands, 100-year floodplains, severe slopes, and buffers) protected during the development review process. Evaluation areas contain environmentally sensitive features (interior forests, colonial waterbird nesting sites, and unique habitat) not currently protected. Network gaps are areas critical to the connection of the regulated and evaluation areas. Preliminary Subregion 5 Master Plan and Proposed Sectional Map Amendment 69 The primary environmental corridors support stream systems that flow generally east to west through the subregion towards the Potomac River. The corridors include the mainstems of the major waterways within the study area and receive most of the depositional runoff from surrounding land uses. The secondary environmental corridors are areas where connectivity is critical to the long‑term viability and preservation of the green infrastructure network, and they are critical to preserving the subregion’s water quality. Conservation and preservation of these corridors, particularly the headwater areas, will preserve and improve downstream water quality, including that of the Potomac River. Table V-1 provides water quality details for the primary corridors. rlb Ma o r o ay P ltw i Be k al e Capit et re B St ra in n a c vania Avenue M h Penn syl Map V-1: Environmental Corridors andA Special Conservation Areas v e n u e Andrews AFB ) Rd d ar dy oo 3 (W R 22 o D s M a r y v il le R o a d M D 5 12 ( k B r e a e n r ) d c C h R s A r y e a v w e k a h t ) n a c i c Tk s n e i a re (P r C 3 B 8 s 2 r r 2 e e l k D t n u k i M e T B re ataway C Pisc Subregion 6 ) y w H in ra C rt FAIRFAX COUNTY e b o (R 1 0 3 S Henson Creek/ U Flo South Potomac ral P Flora a l Pa B r rk u k R oad Ro rc ad h Legend E R B V d ranch I k a o D (Br R ee M 381 andyw R in C r e R C taway n d ca h ) Environmental Corridors is o A P t c s n M g a r O y) in w iv B T L y Primary Corridors H ) h d y t O a e ) w o P d H m 9 H R i n k n T a ee i i k a d o r n cc Secondary Corridors (I A C ( ( 0 3 1 37 1 2 D 0 D M 3 M S Special Conservation Areas U / 5 D 9 - Piscataway Park M M D an Cr 2 tawom ee 2 Mat k 10 8 ( B er ek 10 - Mattawoman Creek Stream Valley ry Rd re ) n C ma wo tta Ma 12 - Potomac River Shoreline Moyaone Reserve Local Conservation Area Countywide and Local Regulated Area 2 1 0 2 CHARLES COUNTY Countywide Evaluation Area Scale in Miles Countywide Network Gap Major Roads Source: Countywide Green Infrastructure Plan, 2005 70 Preliminary Subregion 5 Master Plan and Proposed Sectional Map Amendment Table V-1 Primary Corridors Corridor Subwatershed Index of Benthic Aquatic Habi- 303 (d) list categories2 Integrity Rating1 tat Quality1 Tinkers Creek Tinkers Creek Poor Very Poor Bacterial, Biological, Nutrients, Sediments Piscataway Creek Piscataway Creek Fair Poor Bacterial, Biological, Nutrients, Sediments Lower Potomac Poor Fair Bacterial, Biological, River Nutrients, Sediments, Metals, Toxics Mattawoman Creek Mattawoman Poor Fair Biological, Nutrients, Creek Sediments 1 Countywide Green Infrastructure Plan, 2005. Scale: Good, Fair, Poor, Very Poor. 2 Maryland Department of the Environment, 2006. The 303(d) list is Maryland’s list of impaired surface waters submitted in compliance with section 303(d) of the 1972 Federal Clean Water Act. Special Conservation Areas The Green Infrastructure Plan places special emphasis on special conservation areas (SCAs), which are areas of countywide significance. Three of the ten SCAs in the county are in Subregion 5 (Map V-1, previous page). The largest is the Mattawoman Creek Stream Valley which extends along the southern portion of the study area bordering on Charles County. The other SCAs in Subregion 5 are the Potomac River Shoreline and Piscataway Park. Mattawoman Creek is discussed in more detail below in Section B. Local Conservation Areas Adjacent to the Piscataway National Park in Accokeek, the Moyaone Reserve is identified in this plan as a local conservation area due to its significance as an area with low impact development, two working farms, and Potomac River frontage entirely within the Mount Vernon viewshed across the river in Virginia. Individual lots are five acres or larger and all have scenic easements to protect the view of the Maryland shoreline from Mount Vernon across the Potomac. The easements were acquired by the Accokeek Foundation in the 1960s and 1970s and eventually deeded to the federal government. Many of residents of the Moyaone Reserve have a strong conservation ethic and are involved in the environmental education activities of the Hard Bargain Farm at the Alice Ferguson Foundation. Since this plan recommends rezoning all remaining rural tier properties to the O‑S Zone, the Moyaone Reserve can effectively act as an example and model for how the aims of protecting both landowner value and the environment can coexist. Special conservation area designation ensures that development within an area of influence to the Moyaone Reserve will be evaluated for its impacts to the environmental, scenic, and community character of the area. Preliminary Subregion 5 Master Plan and Proposed Sectional Map Amendment 71 Woodlands, Wildlife and Habitat Subregion 5 is home to diverse terrestrial habitats, including large tracts of woodlands, grasslands, and wetlands that support a rich diversity of wildlife. Forested areas cover approximately 26,000 acres and comprise over half (55 percent) of the subregion’s total area. Woodland characteristics vary within the subregion with dominant deciduous forests in the southern part of the subregion and areas of mixed deciduous or coniferous forests towards the northwest near Hyde Field and Friendly High School. Small pockets of coniferous forests are also interspersed across the master plan area. Urban and rural forests and woodlands have been damaged and continue to be threatened by human and natural forces, such as sprawling development, insufficient care or maintenance, poor harvesting practices, wildfire, and insects and disease putting ecosystem viability at risk. When trees and forests are damaged, ecological services such as air and water quality, wildlife and fish habitat, are degraded and nearby communities suffer, sometimes showing signs of economic and social decline. Woodlands reduce runoff, erosion, and air pollution and provide habitats for wildlife. The largest contiguous forest tracts are located along Piscataway Creek and the Mattawoman Creek Stream Valley, in the south central portion of the subregion. Much of the subregion’s woodlands are included in the green infrastructure network. Smaller pockets of woodland are scattered throughout the subregion outside the green infrastructure network. Open grasslands, which provide unique habitat for a variety of species such as ground‑ nesting birds, are quickly disappearing due to development on open lands. Grasslands are not prevalent in the subregion; only approximately four percent of the total land area is classified as open land or pasture that might support grassland, but many of these areas are undeveloped parcels in urban settings or managed areas (golf course and athletic fields). Some grasslands can be found in portions of Piscataway Creek Stream Valley Park in the eastern portion of the study area.