ENVIRONMENTAL ASSESSMENT FORM. Part 1 Resource Identification. Enclosure C Description of Aquatic Habitat

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1 ENVIRONMENTAL ASSESSMENT FORM Part 1 Resource Identification Enclosure C Description of Aquatic Habitat SECTION 8 A. AQUATIC HABITATS: (1) Food chain production: Tumble Brook drains a watershed containing predominantly open space, agriculture and residential land uses. There are several tracts of large woodlands located in the watershed. Tumble Brook also meanders through a golf course appropriately named Tumble Brook Golf Course. The land use within the project area is residential, downstream of the existing bridge and open space upstream of the existing bridge. The residential properties have maintained lawns that buffer the stream and the owners have left a small width of natural streambank vegetation growing on either side. Forested and herbaceous wetlands occupy the majority of the upstream project area. The upstream project area has excellent riparian cover comprised of relatively mature woodlands. Tumble Brook is tributary to the South Branch of the Saucon Creek located some 300 feet downstream of the existing bridge. The South Branch of the Saucon Creek is listed in the Pennsylvania Fish and Boat Commission s 2003 list of Approved Trout Waters. This listing indicates that the watercourse meets specific water quality criteria deemed adequate for the stream to be stocked with trout. However, this listing also indicates that the stream does not contain a sufficient quantity of naturally reproducing trout capable of sustaining its population without the assistance of regular stocking. Pennsylvania Code Title 25, Chapter 93 sets forth water quality standards for surface waters of this commonwealth, including wetlands. Those standards are based upon water uses which are to be protected and are considered by PADEP in its regulation of discharges. Under Chapter 93, Tumble Brook is not specifically listed but falls under the listing of Saucon Creek Basin. The entire Saucon Creek basin is classified as Cold Water Fishes (CWF). The CWF classification indicates that the water quality will be protected for the maintenance and propagation, or both, of fish species including the family salmonidae and additional flora and fauna which are indigenous to a cold water habitat. There has been no quantitative study performed on this section of Tumble Brook as part of this study. Rather, quantitative water quality classifications and studies provided by the Pennsylvania Fish and Boat Commission and the Pennsylvania Department of Environmental Protection are sufficient for the scope of this report. However, based on qualitative observations and the criteria that promote productivity within streams, it is a fair assumption that Tumble Brook has good food chain production and supports a diverse and productive population of macroinvertebrates, aquatic vegetation, fish,

2 amphibians, birds and mammals. The flow of water within the project area cascades over various size gravels and cobbles creating turbulence that increases contact with the atmosphere, enabling a higher degree of dissolved oxygen. Tumble Brook also has a significant amount of organic material deposited within the stream corridor that is consumed by first-order detritus processing organisms, which in turn, provides food for secondary consumers. Production in a stream corridor is also influenced in part by the material on the stream bottom. The substrate is composed of various size gravels and cobbles, providing macroinvertebrates adequate surface area and protection. The majority of the stream inhabitants live in riffles, on the underside of rocks and gravels. A major reason for the richer aquatic life in the riffles is the current. Stream animals depend on flowing water to aid in their respiration and bring them food. Water temperature also plays a significant role in the growth and development of aquatic species, particularly the distribution of fish species. Salmonids typically dominate the coldwater streams. Stream temperature is ultimately influenced by the surrounding land use and hydrogeologic conditions of the watershed. (2) General habitat: Residential properties are located immediately downstream of the subject bridge on either side of the stream with maintained lawns buffering the streambanks. Mature vacant woodlands are located immediately upstream of the bridge on both banks. Overall, there is generally good vegetative cover within the riparian corridor. A petroleum pipeline is located adjacent and directly south of the stream corridor. Tumble Brook is considered part of the Saucon Creek Watershed, which drains an area of approximately 57.9 square miles. Tumble Brook is tributary to the South Branch of Saucon Creek, which in turn drains to the Lehigh River. The South Branch of the Saucon Creek is located approximately 300 feet downstream of the existing bridge. Two unnamed tributaries join the main stem of Tumble Brook approximately 275 feet upstream of the existing bridge. Tumble Brook is identified as a perennial stream on the USGS 7.5 minute series topographic quadrangle, flowing in a general east to west trend. Tumble Brook is not listed and has not been nominated as part of either the National or State Wild and Scenic Rivers system. Overall, Tumble Brook provides excellent habitat for cold-water aquatic species. Additionally, the riparian corridor provides adequate habitat for nesting, spawning, rearing, resting, migration, feeding and escape cover. (3) Habitat for Threatened and Endangered plant and animal species: Correspondence with various natural resource agencies including the Pennsylvania Natural Diversity Inventory (PNDI), United States Fish and Wildlife Service, Pennsylvania Fish and Boat Commission and the Pennsylvania Game Commission are included with this submission. The project is located within the known range of the State Endangered and Federally Threatened Bog Turtle (Clemmys muhlenbergii). A Phase I Bog Turtle Habitat Evaluation Survey was conducted in accordance with the United States Fish and Wildlife Service "Guidelines For Bog Turtle Surveys". The U.S. Fish and Wildlife Service concurred with the findings of that report that indeed Bog Turtle habitat may be present along the corridor of Tumble Brook, especially in the southeast quadrant (within the pipeline easement). Only the proposed upstream bridge wingwalls and rip-rap apron will encroach on this potential habitat area. Avoidance measures will ensure that no impacts to bog turtles will occur as a result of construction activities. This

3 determination is documented in the minutes of a field view conducted September 12, 2002 with the U.S. Fish and Wildlife Service, and letters received from the U.S. Fish and Wildlife Service and the Pennsylvania Fish and Boat Commission. (4) Environmental study areas: There are no environmental sanctuaries or refuges within close proximity to the project area. (5) Stream relocation, stream enclosure or dredging: It is likely that the existing stream channel was either straightened or relocated at some point in the past to accommodate the construction of the existing roadway and or the remnant trolley tracks that are located immediately upstream of the bridge. Farther upstream, it is apparent that an unnamed tributary leading to Tumble Brook was straightened to accommodate the construction of a paved parking area for a commercial property near S.R The existing bridge is not considered a stream enclosure. No evidence of past dredging is present at the site. B. WATER QUANTITY AND STREAM FLOW: (1) Natural drainage patterns: The project study area is situated within the Gettysburg-Newark Lowland Section of the Ridge and Valley Physiographic Province of Pennsylvania. The Gettysburg-Newark Lowland Section is characterized by rolling lowlands, shallow valleys and isolated hills. Surface drainage patterns are dendritic and trellis. Tumble Brook drains from its source in Bucks County, located approximately 1.7 miles southeast of the project site. The source elevation is approximately 580 feet above mean sea-level and the elevation of the streambed at the existing structure is approximately 440 feet above mean sea-level. The contributing watershed upstream of the structure is approximately 2.9 square miles, as delineated from the Allentown East and Hellertown topographic quadrangle maps. There are no FEMA Flood records available for the project area to compare flow analysis. Stream flows were determined by the procedure outlined in PSU-IV for estimating design flood peaks on ungaged watersheds. Table 1 in the accompanying Hydrology and Hydraulic Report summarizes the design flood discharges. Stream gradient through the project area averages less than a half of a percent. The pool to riffle ratio is close to and the spacing between pool and riffle sections averages approximately 20 feet. Downstream of the bridge, the main channel averages between 10 to 15 feet and between 20 to 30 feet from top of bank to top of bank. The stream channel is more defined on the downstream side. With minor exceptions the stream banks appear stable and the streambed appears to be in good condition. The stream banks are vegetated with shallow rooted grasses and deep-rooted trees and shrubs. There is an adequately sized pool approximately 4 foot in depth located on the immediate upstream side of the bridge. The existing structure is a single span, however the flow through the structure has been bisected by one of the remnant trolley piers. The main flow of the

4 channel is directed to the northern half of the bridge because of the location of the trolley pier. A small rivulet flows through the southern half of the bridge. Both flows come together underneath the bridge to form a single uniform channel on the downstream side. The location of the trolley pier has caused deposition immediately upstream of the bridge creating a significantly large gravel island with wetlands. The gravel island is approximately 3,200 square feet. Because of this deposit, the main flow of the stream approaches the bridge at a very acute angle and is actually causing bank erosion near the northeast abutment. Prior to the deposition of the gravel bar, the flow of the stream likely entered the bridge at an angle close to perpendicular. The existing approach angle of the main channel is less than ideal. There are no reservoirs located upstream of the bridge that could artificially alter the flow regime of Tumble Brook. There are two structures located upstream of the existing bridge. One carries a small unnamed tributary to Tumble Brook under S.R, 309 approximately 1,000 feet upstream of the existing bridge. The second structure carries the main stem of Tumble Brook under S.R. 309 approximately 1,700 feet upstream. Both of these structures were designed to convey the 50 year flow event. There is also a small pipe culvert that crosses S.R. 309 between the aforementioned culverts located approximately 1,400 feet upstream, which eventually drains to the unnamed tributary to Tumble Brook. (2) Flushing characteristics: Tumble Brook has historically regularly flooded at the location of the existing bridge. In fact, The Act 167 Stormwater Management Plan for the Saucon Creek Watershed identifies that location as an existing storm drainage problem area. Because of the nature of the existing channel with respect to the alignment of the bridge, there is a good chance for debris to clog near the existing trolley piers. Adjacent floodplains are wooded providing ample material to accumulate in the stream corridor. The location of the existing gravel bar also impedes the flushing efficiency of the bridge. However, during baseflow conditions this does not appear to be a problem. (3) Current Patterns: The hydraulic capacity of the existing structure is such that for the 10, 25, 50 and 100- year storm events, the flood water surface elevation passes below the low chord of the structure. Thus, the existing structure, carrying S.R over Tumble Brook, is not overtopped for any of those storm events. As previously mentioned, there is a possibility of debris accumulating near the structure. Hydraulic calculations for the existing structure prepared with HEC-RAS indicate the mean velocities through the existing bridge range between 6.22 fps for the 25 year storm event and 8.88 fps for the 100 year storm event. (4) Groundwater discharge for baseflow: The project area is underlain by the Brunswick Formation. The Brunswick Formation consists of reddish-brown shale, mudstone and siltstone. Joint, cleavage, and solution openings provide moderate secondary porosity and moderate permeability. Reported groundwater median yield is 60 gallons per minute for wells ranging in depth from 200

5 to 550 feet, with sandstone and conglomerate showing the highest yield. In general, well yields in the Brunswick Formation increase as wells are deepened. The water in this formation is generally of good quality. Surface drainage is relatively good. Groundwater elevations in this formation typically correspond to surface contours. There were no apparent springs or seeps during the site investigation and none were located on Topographic and Geologic Survey Mapping. However, it is probable that a sufficient amount of groundwater discharge is responsible for baseflow. The volume of groundwater discharge within the streambed has not been quantified for this environmental assessment. (5) Natural recharge area for ground and surface waters: It is assumed that natural recharge and groundwater discharge are freely exchanged. This of course is dependent on the season and recent weather patterns. Historically, pumping of groundwater in the Saucon Creek basin from the Friedensville Zinc Mine significantly altered the relationship between groundwater and surface water flows. Between 1953 and up until 1983, large amounts of water were pumped from a mine shaft and discharged in the nearby Saucon Creek. The pumping at the mine created depressed groundwater levels in the Saucon Creek watershed extending from Hellertown to Upper Milford and from South Mountain to Center Valley. Lowered groundwater levels resulted in loss of water from shallow wells and springs for many residents necessitating the extension of public water supplies. However the mine is no longer in operation and the pumping ended in Since that time the hydrology of the basin has reached a new equilibrium, presumably similar to that of pre (6) Storm and floodwater storage and control: A FEMA Flood Insurance Study (FIS) is available for the project area, however, the project area does not fall within a detailed study area. Design flood discharges were calculated using the procedures outlined in PSU-IV for estimating design flood peaks on ungaged watersheds. The existing Bridge is located within the 100-year floodplain of Tumble Brook. According to the Hydrologic and Hydraulic Report, the existing structure is overtopped for the 10, 25, 50 and 100 year storm events. All development within the Tumble Brook watershed must meet the stormwater discharge requirements contained within the Act 167 Stormwater Management Plan for the Saucon Creek Watershed. That report identified the location of the bridge as an existing storm drainage problem area. C. WATER QUALITY: (1) Preventing Pollution: The vegetated riparian corridor along Tumble Brook enhance the natural filtration of runoff from upland areas, helping to prevent pollution from entering the aquatic environment. In addition, the flow characteristics of Tumble Brook provide adequate mixing and aeration of the water column to enable biological decomposition of some organic pollutants, especially nutrients. (2) Sedimentation control and patterns:

6 The vegetation within the floodplain and along the streambanks of Tumble Brook both control erosion and act to filter sediment from upland tributary areas. Sediments have accumulated immediately upstream of the existing bridge and trolley tracks, forming a relatively large gravel bar. The gravel bar will likely continue to accumulate coarse sediments unless a new state of hydraulic equilibrium is reached. (3) Salinity distribution: There has been no chemical analysis to determine the salinity distribution of Tumble Brook. Tumble Brook is a fresh water stream. Some salts may be present in the water if dissolved de-icing salts are washed to the stream from the roadways in the winter. (4) Natural water filtration: Natural water filtration occurs at the project site when upland runoff seeps through the surrounding vegetation before entering Tumble Brook. D. RECREATION: (1) Game Species: Various game species are located within the project area including deer, fox, rabbits, groundhogs, turtles, ducks, muskrat, turkey and fish. The project area is not a wildlife sanctuary, but because of the rural setting, abundant wildlife is present. (2) Non-Game Species: Various non-game species are located within the project area including snakes, skunks, weasels, birds, insects, turtles and owls. (3) Fishing: (4) Hiking: The South Branch of the Saucon Creek is listed in the Pennsylvania Fish and Boat Commission s 2003 list of Approved Trout Waters. This listing indicates that the watercourse meets specific water quality criteria deemed adequate for the stream to be stocked with trout. However, this listing also indicates that the stream does not contain a sufficient quantity of naturally reproducing trout capable of sustaining its population without the assistance of regular stocking. Fishing is limited by the lack of public access at this location. There are no formal pedestrian facilities located along the roadway or along the stream. The existing bridge actually constrains the existing roadway and makes it dangerous for safe passage of both pedestrians and motorists. (5) Observation:

7 Tumble Brook is a small tributary draining to the South Branch of the Saucon Creek located immediately downstream from the existing bridge. The project area suffers from periodic flooding because of the low topography. The gravel bar immediately upstream from the bridge bisects the flow through the existing structure, decreasing the hydraulic efficiency and increasing the potential for bank erosion on the upstream side. The streambanks are relatively stable on the downstream side of the bridge. The existing structure is dangerous for both pedestrians and motor vehicles because of the narrow width of the bridge. E. UPSTREAM AND DOWNSTREAM PROPERTY: The existing structure is located within PennDOT right-of-way. However, narrow frontage strips of additional right-of-way will be required to construct the proposed bridge and roadway improvements. Overall, six parcels will be affected, all privately held. Private property is located both upstream and downstream of the existing structure, adjacent to the stream. Property lines are delineated on the accompanying plans. F. OTHER ENVIRONMENTAL FACTORS DETERMINED BY SITE INVESTIGATION: There are no other significant environmental factors relevant to this project.