Riverbank Geology

Authors Roman G. Kyshakevych, Ph.D. Henry Prellwitz, Ph.D.

3 Rivers 2nd Nature STUDIO for Creative Inquiry Carnegie Mellon University Riverbank Geology Table of Contents

I. Abstract...7

II. Geological Setting...7 A. Geological Time B. Geological Time and a Geological History of the Allegheny River

III. Data Aquisition and Analysis...10 A. Field Methods B. Access Descriptions C. Bank and Berm Materials : Man-made D. Bank and Berm Materials : Natural

IV. Results and Discussion...14 A. Data Analysis B. Access C. Preservation D. Restoration E. Riverbank Grain Size and Material Type Trends F. Comparison: Allegheny and Monongahela Rivers

V. References...18

VI. Appendices Appendix A. Figures...19 Appendix B. Maps...37 3R2N Riverbank Geology, Phase 3 - 2002

I. Abstract II. Geological Setting

The intent of the 3R2N terrestrial study is A. Geological Time to describe and document conditions of riverbank In order to present a geological history of geology, accessibility, preservation, and restoration the Allegheny River, the rocks through which it flows, potential along the Allegheny River in Pools 1, 2, and the ages of the materials transported by the 3, and 4, Allegheny County, Pennsylvania. Data river, a discussion of the amount of time is presented, collected during the 2002 field season includes bank using the geological time scale used today (fig. 1). and berm slopes, heights, material types and grain This time scale is divided into Eras and Periods. The sizes, material conditions, accessibility potential, bedrock layers exposed in the Allegheny River valley and floodplain identification. Data was collected from Freeport, Pennsylvania (Pool 4) to downtown along 1/10th mile sections of each bank, which Pittsburgh (Pool 1) are from the Pennsylvanian were identified in the field with a Global Positioning Period, in Paleozoic Era (meaning “old life”) dating Receiver (GPS). This data was entered into a database from about 300 million (ma) years ago. If one were for later GIS and ARCINFO analysis. Riverbank access to drill a hole in Pittsburgh, down through 16,000 was graded into three categories, and mapped with feet of sedimentary layers, much older rocks will ARCVUE computer software. Preservation data was be found, from the Precambrian Era, about 1,200 also graded into three categories, and mapped. The ma (million years ago). These ancient crystalline data from the access and preservation maps was rocks (non-sedimentary) are exposed on the surface filtered through a Boolean truth chart, and riverbank about 150 miles north of Toronto, Ontario, Canada, sections worthy of restoration were identified, and in the Philadelphia area in Pennsylvania. The graded, and mapped. Riverbank grain sizes and simplified geological time scale (fig. 1) illustrates materials distribution were plotted for each pool, and the Eras and Periods. The sedimentary beds exposed the resulting trends discussed. in the Allegheny River valley are shown in the local stratigraphic rock column, which shows an expanded portion of the Pennsylvanian Period (fig. 2), and range from the middle Conemaugh Group (all of the Glenshaw Formation, and most of the Casselman Formation) and the upper portion of the Allegheny Group.

B. Geological Time and a Geological History of the Allegheny River The present-day Allegheny River flows southward from New York and Pennsylvania, to its confluence with the Ohio and Monongahela Rivers at Pittsburgh, Pennsylvania. It is slowly eroding and downcutting through the bedrock of the Pittsburgh region, which consists of flat-lying sedimentary beds of shale, sandstone, limestone, clay stone, and coal that were originally deposited during the Pennsylvanian Period of geological time (about 300 million years ago). These bedrock layers can be seen from certain points along the Allegheny River today (fig. 3). During this time of rock formation, the river drainage system and topography were

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totally different from that seen today; the ancestral erosion. The erosional style during the early Cenozoic rivers flowed west into a shallow sea that covered Era was one of sidecutting, with large river meander Western Pennsylvania and Eastern Ohio. The climate loops. As the Allegheny flowed faster due to uplifted was tropical, as the equator was very close to the land, and a greater downslope river gradient (with Pittsburgh area due to continental drift. Figure 4 is a a larger resulting erosive capability), the river’s paleogeographic map of Pennsylvania, as of about course straightened out somewhat and sideways 300 million years ago. The climatic environment at erosion was abandoned to greater downward erosion. this time in Pennsylvania’s history was similar to Deep valleys were then cut, about 400 feet below that of the Amazon River delta in Brazil; the climate the elevation of the plain formed during the early was very hot and steamy, with high amounts of Cenozoic Era. If one looks out at the Pittsburgh rainfall. This type of climate in the ancestral Western landscape from a high point (such as the USX Tower Pennsylvania area was due to its proximity to the downtown) one can see that all the hilltops are level, earth’s equator; processes of continental drift have and represent the remnants of this old plain (fig. 5). moved the North American continent northward about The downcutting action of the Allegheny continued 45° latitude. Plants grew quickly in this environment; until the river’s water level was about 200 above that and then decayed, and formed thick layers of organic seen today. matter that was later was compressed and changed There was a temporary hiatus of the to coal. Huge insects lived in this environment, with downward erosion of the Allegheny, and this was some dragonfly species having a wingspan of over affected by the advance of the great ice sheets that thirty inches. The rivers that drained this ancestral covered Northwestern Pennsylvania during the “ice landscape flowed from east to west, into the shallow ages.” There were four ice sheet advances during sea that covered much of Western Pennsylvania and this time period, but the next to the last ice advance Ohio at that time; the beds and channels of these old radically changed the courses of some of our rivers. rivers have no relationship to those of the rivers now The Allegheny River has not always flowed seen in the region. The sources for these ancestral south, emptying into the Ohio River, with the rivers were in the mountains to the east, which Monongahela. Before the third ice advance, the Ohio predated the Appalachians. River originally flowed north into Lake Erie, in the The history of the Allegheny River as we know valley of the present-day Beaver River. The ice sheet it today probably began back at the beginning of the advance dammed the north-flowing Ohio River, and Cenozoic Era, about sixty million years ago (Wagner, water impounded behind it forming a large valley-fill 1970). During this time, Western Pennsylvania was lake. This lake, called “Lake Monongahela,” probably a broad, flat plain similar to those now seen in the formed between 750,000 and 970,000 years ago mid-western United States. There was probably very (Marine and Donahue, 2000). Thick deposits of sand, little topographic relief, and there was little elevation mud, gravel, and cobbles can be seen in certain difference between the tops of any hills and the water places within Pittsburgh, at about 920 feet above levels of the Allegheny. The topog+raphic relief in sea level; this deposit is known as the “Carmichaels Pittsburgh is now nearly 700 feet, as the level of the Formation,” or the “Parker Strath” (Wagner, 1970). water in the Allegheny at the Point is 710 feet above These unconsolidated sediments represent material sea level, and the tops of the highest hills are almost deposited by the Allegheny and Monongahela Rivers 1400 feet above sea level. when they were impounded by glacial ice to the During the late Cenozoic era (about five north. Figure 6 represents these terrace deposits and million years ago) geological processes slowly abandoned loops in the Pittsburgh area, and figure uplifted the Pittsburgh area, increasing the slope of 7 shows these deposits in Allegheny County. Marine the Allegheny River, allowing it to start downcutting and Donahue (2000) have found evidence for this

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lake as far south as present-day West Virginia. The Figure 9 is a map of the present drainage patterns Cathedral of Learning (University of Pittsburgh) and in Western Pennsylvania, showing also the furthest the Carnegie Museum of Natural History both rest advance of glacial ice. on the Carmichaels Formation deposits. Sometime during this high water event, the southern portion of the Ohio River eroded through its divide, and started to flow southward. Before the advance of the glacial ice, there were three ancestral rivers that combined to form the Allegheny River as we know it today. Figure 8, showing the pre-glacial river drainage of Western Pennsylvania, has the “Upper Allegheny” River flowing northwestward from northern Pennsylvania into New York, and into the ancestral Lake Erie basin. The “Middle Allegheny” River flowed southwestward from Tidioute, PA., and then turning northwest into the Lake Erie basin. Much of this “Middle Allegheny” river moved in the bed of present French Creek. The “Lower Allegheny” River followed the present-day bed closely, with a confluence at the site of Pittsburgh, with the Monongahela. The resulting ancestral Ohio River flowed northward into the Lake Erie basin. This river followed the bed of the present-day Beaver River for a short distance. As the glacial ice finally retreated, the old Ohio River divide was eroded through, and all the water from the Allegheny flowed southward to the Mississippi River, as it does presently. Lake Monongahela drained, and the river started again on its downcutting action. There was a fourth ice advance that deposited a blanket of unconsolidated glacial till in the northern portions of the Allegheny River drainage basin and much of this material was deposited in the Allegheny riverbed, due to outwashing from the surrounding hills. One of the major differences between the Allegheny and Monongahela riverbank and bottom materials is the introduction of glacial alluvium, which the Monongahela lacks. Downcutting remains the major erosional style of the Allegheny, even though there is still some meandering and sidecutting. The water level of the Allegheny dropped about 200 feet, since the third ice advance; this may give an idea of how slow erosional processes are on a major waterway.

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III. Data Aquisition and Analysis

A. Field Methods bedrock, boulders, cobbles, gravel, sand, mud, and The field work for Year 3 of the project was “other.” Driftwood piles and other garbage that confined to Pools 1, 2, 3, and 4 of the Allegheny deposited or dumped on the berm were not included River, from Freeport, PA, to the point at Pittsburgh, in any of the geological descriptions. PA. Pool 1 of the Allegheny River starts at Pittsburgh, The descriptions for the riverbanks were and ends at Lock and Dam #2, in Highland Park; Pool described using the same procedure as the berm; the 2 starts at Lock and Dam #2 in Highland Park and bank slope was reported in degrees, the grain size ends at Acmetonia, PA. Pool 3 starts at Lock and Dam distribution of the bank materials was determined, #3 at Acmetonia and ends at Lock and Dam #4 at and the percentages of the natural and manmade Natrona, PA. Pool 4 covers the Allegheny River from materials was recorded for each 1/10th mile bank Natrona, PA to Lock and Dam #5, at Schenley, PA, just section. upriver from Freeport, PA. Schenley, PA is near the The condition of the berm and bank materials confluence of the Allegheny and Kiskiminetas Rivers. was reported as “consolidated” or “unconsolidated.” Both banks of the Allegheny River (and the An example of a consolidated bank would be a steel banks of the islands) were divided into 1/10th mile bulkhead, or a stone block wall. Unconsolidated sections. These section’s start and stop points were natural bank and berm materials include sand, gravel, programmed in to a GPS (Global Positioning System) cobbles, silt, and mud. Manmade materials can also receiver unit as latitude and longitude points. This be unconsolidated, including slag piles, and coal GPS receiver was used aboard the field vessel to mine waste dumps. determine each section’s starting and ending point. Along with the berm and bank slope The geology and geometry of the riverbank steepness number (in degrees), four categories of and/or berm was described for each 1/10th mile steepness were recorded. The first, “vertical,” implies section. If a berm was present in a section, its slope a 90° “slope.” A “steep” bank or berm is one that was reported (in degrees) and the average grain size has a slope greater than 45°, but is not vertical. A distribution data was recorded. A modified version of “moderate” slope is less than 45°, but greater than the Wentworth-Udden scale of grain sizes was used to 22°; and a “slight” bank or berm slope is less than or report data for this study (Boggs, 1987): equal to 22°. The bank and berm slopes were measured Boulder Size > 256 mm. using a wooden Jacob’s Staff, and a geological Cobble Size > 64 mm., < 256 mm. compass that has a built-in clinometer. The Jacob’s Pebble Size > 4 mm., < 64 mm. Staff was placed parallel with the slope to be Coarse Sand Size > 1 mm., < 4 mm. measured, and the compass was placed on the staff, Sand Size > 1/16 mm., < 1 mm. and an angle in degrees was then recorded. Most Silt Size > 1/256 mm., < 1/16 mm. berm slopes were less than 25°, and bank slopes Clay Size < 1/256 mm. usually were greater than 45°. The bank height measurements were determined by line-of-sight from Along with the grain size distribution data, the opposite bank, or the middle of the river, using and the berm slope in degrees, the percentages an object with a known height (such as a building, of natural and manmade materials were recorded or a railroad freight car) for comparison. Bank for each section. Manmade materials include slag, heights were also determined by climbing the bank, cement, steel, wooden bulkheads, gabion, stone noting its slope, and estimating height using simple block, rubble, and “other.” trigonometric relationships. Natural materials (if not moved and Bank and berm accessibility was reported as deposited by human operations) were classified as “easy,” “moderate,” and “no access.” Easy access

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(from the water side of the bank and/or berm) usually Figures 13, 14, 15, and 16 are areas that had a berm with a slope of less than 22°, and a have difficult, but possible access. There is a lack material grain size distribution that allowed easy of berm in these examples, the grain sizes of the landing from a boat. Large boulders inhibit access, as bank materials are very coarse (boulder sizes), and does thick, soft deposits of mud and silt. The berms the bank slope is steep, prohibiting easy landing that had the easiest access had a large amount of from the water. Figure 13 is a portion of bank where sand, coarse sand, and pebble sized material, and large boulders of natural bedrock have slid down the a small amount of cobble sized grains. Steep banks bank, and lie at the water’s edge making access very with no berms (and bank slopes greater than 45°) difficult. Figure 14 depicts a similar situation as in generally had more difficult access, and a vertical wall figure 13, but the boulders were placed by man, as or bulkhead was classified “no access.” a bank stabilization tool. Figure 15 is a portion of the Grain size distributions for the bank and left bank of the Allegheny River just below Lock and berm materials were measured by picking one Dam #4, at Natrona, Pa.; the bank has been stabilized spot of the bank or berm (about 1 meter square) with boulder to cobble sized stones, set in an orderly if the rest of the 1/10th mile section had similar fashion. The dam highwalls upriver are vertical, or material characteristics. If the grain size of the bank “no access” areas. Figure 16 is a steep bank built and/or berm material changed significantly in one up using industrial waste, including slag and coal section, then an overall size distribution average mine refuse. The bank is steep, there is no berm, and was reported. Banks that were covered by dense boat landing is difficult here, classifying this as a vegetation were sampled with a shovel to determine “moderate” to “difficult” access area. materials and grain size ranges. Berm and bank areas Figures 17, 18, 19, 20, 21, 22, and 23 all that appeared to be in a natural state were sampled, show bank and berm conditions along the Allegheny and the material was sieved to determine grain size River that have “easy” access conditions. Figure 17 is distribution ranges. a photograph of a wide berm, with a slight low bank in the background. This is “easy” access, but not B. Access Descriptions ideal access, as the berm has a high concentration Figures 10, 11, and 12 show riverbanks that of silt and mud, making a boat landing slightly are vertical, and have consolidated materials that are unpleasant, due to soft conditions. Figure 18 has manmade. These banks are classified under the “no ideal accessibility; the berm slope is slight, and access” category. Figure 10 is a high cement dock, the materials consist of sand and course sand, now inactive, that was once used by PPG Industries, making boat landing easy and pleasant. The low near Glassmere, PA. This wall is over twenty-five feet bank (about twelve feet high) is also very sandy, high. Figure 11 is a steel bulkhead used as a dock and this is a typical low floodplain deposit, usually for Allegheny Ludlum Steel Co. in Natrona, PA. These seen on the inside of river bends. This is also known walls are over twenty feet high. The third photograph as a “point bar” deposit. The berm shown in figure (fig. 12) is an example of a vertical high wall built 19 is of coarser material than in the previous two from large interlocking cement blocks, used as a photographs; most of the material is pebble size, barge loading dock. Many industrial sites along the with about 20% of the berm as cobble size grains. Allegheny River utilized an unsaleable waste product This berm has easy access, as landing here was not as a building aggregate, increasing the amount of difficult or unpleasant, due to lack of soft mud and level land above high flood stage. silt. Figures 20 and 21 also show easy access, which Other areas of “no access” include the are both in more natural settings; in both cases, the riverfront adjacent to lock and dam structures, and bank heights are low, and the berm is wide with a portions of the bank blocked by shipping activity. slight slope. Figures 22 and 23 are examples of easy

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access, but these areas are less aesthically pleasing, amount of coal. The local bedrock in the Allegheny as the berm and bank materials consist of industrial River basin is similar to that of the Monongahela River waste products. The ease of landing a small boat at watershed, except for a lesser amount of coal. Figure these sites is not hampered, however. 27 shows large natural boulders of local sandstone C. Bank and Berm Materials: Man-made that have slid down to the water’s edge. Man-made bank and berm conditions Figures 28 and 29 are photographs of a were observed during the 2002 field season on the large gravel bank on the north side of Jack’s Island. Allegheny River. Unconsolidated man-made bank This bank is about 10 feet high, and consists mostly and berm materials include steel mill slag, coal mine of cobble sized material, with a lesser amount of refuse piles, cement plant waste material, boulders pebble and sand sized grains. Much of this material dumped along the bank to stabilize erosion, and has been introduced to the area, from transport by material dumped as fill for railroad and highway glacial ice. Much of the exotic material is from the rights-of-way. Consolidated man-made materials Canadian Shield, which is made up of pre-Cambrian include cement docks and bulkheads, stone and brick rock, ranging in age from 1.2 to 2.6 billion years old. walls, structures at water level (fig. 24), steel and A one meter square was imposed on a flat portion of wood retaining walls, dumped cement, and solidified this gravel bank, and a cobble count performed; the slag. Other man-made materials that do not fall into results are as follows: the above categories include odd trash dumped along the riverbank, and occasional wrecks (fig. 25). Local sedimentary material Examples of consolidated man-made bank materials (sandstone, shale, etc.) 67% are cement walls, steel piling walls, and cement block walls (fig. 10, 11, and 12). Figure 26 shows a mixture Exotic sedimentary material of man-made materials: the railroad line is built on (sandstone, limestone, etc.) 14% introduced fill, including slag and natural material. The berm, along the water’s edge, has been covered Exotic metamorphic material with introduced boulder sized natural material (gneiss, quartzite, etc.) 17% (sandstone) to control erosion. D. Bank and Berm Materials: Natural Exotic igneous material The majority of the banks and berms along (granite, gabbro, etc.) 2% the Allegheny River consist of natural materials. These materials are all unconsolidated, except for The exotic sedimentary cobbles were one exposure of natural bedrock near Lock and Dam identified by fossil content and species; this #4. Natural materials include boulders, cobbles, percentage could be higher, if ambiguities in field pebbles, sand. silt, and mud. The boulders, cobbles, identification were eliminated. Most fossils collected and pebbles are from local sources, as a product of from introduced sedimentary rocks were of Silurian normal weathering, or introduced, from the outwash age (fig. 1, Geological Time Scale) and these rocks of glacial materials transported by ice. Some of the are exposed on the surface in the Buffalo, New York introduced materials have been brought in from area, but deeply buried in the Pittsburgh region. sources over 1000 kilometers to the north, from Since there are no surface exposures of metamorphic Canada. or igneous rocks within the Allegheny River drainage Local natural bank and berm materials are basin, these cobbles are definitely of exotic origin, similar to those found in the Monongahela River; even though they were transported and deposited by the parent rocks which they have weathered from natural processes. Metamorphic rocks occur about consist of sandstone, shale, limestone, and a small 16,000 feet down in the Pittsburgh area.

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Figures 30 and 31 show a berm and bank, amount of mud) along with a bank that is mostly mud. respectively, that have a slightly finer grain size This is a good example of a low floodplain that is distribution that at Jack’s Island. Most of the gravel about ten feet high above water level, and is probably here is pebble size, with some larger cobbles underwater once every five years. The berm is mostly included, and a greater amount of sand. The berm has sand, with some pebble sized grains, mixed with a shallow slope (allowing good access) and the bank mud. Access is good here, as boat landing is easy. is not too steep to easily walk up, allowing fine access Figure 17 is a berm that is about 50% sand and 50% to the road above. The materials here are mostly of mud; access is also easy here, if one steps from their local origin; about 15% of the pebbles and cobbles boat onto the sandy areas, and avoids the mud. In are exotic. A few fragments of man-made introduced this specific locality, mud has been deposited on top material can be seen in figure 30, in the form of coal, of the sand layer, from a flooding event. Figure 33 is a bricks, and cement blocks. The natural grains (pebble berm that is 100% mud; access is unpleasant here, as and cobble sizes) are well rounded, implying a certain one will sink quickly in the mud when stepping from a amount of transportation (by water and ice) from the boat. original source. By contrast, most larger sized grains A small stream delta into the Allegheny in the Monongahela River are more angular in shape, River is shown in figure 34. This particular stream inferring shorter movement distance from their is Chartier’s Run, on the southeast bank of the source. Allegheny, in Pool 4. The Allegheny is flowing from Figure 19 is a shallow angled berm, with left to right in this photo. In this case, the coarser a large sand percentage. This bimodal grain size material is on the upstream side of the delta, and distribution is common along the Allegheny River, the finer material is downstream. This is due to the with berm areas that consist of cobbles and sand slowing action of the delta deposits during flooding only. The cobbles here are very well rounded, and events, where finer grained material drops out of appear to have been transported a long distance. a moving river when slowed. The initial impact of This berm is composed of over 50% exotic (natural) moving floodwater on the delta (just before it slows cobbles, with over 30% of the cobbles igneous and down) is to remove fine grained sediments on the metamorphic rocks. Access is clearly easy here, as upstream side. This is also true for many of the the berm slope is slight, and the shore is sandy, Allegheny River islands, where the upstream end is permitting easy small boat landing. being eroded, and the downstream end is a site for A berm that grades downstream from cobble sediment deposition. The islands very slowly migrate to pebble to sand sized grains is shown in figure 32. downstream from these erosion and deposition This berm is on the southeast bank of Jack’s Island, processes. just above Lock and Dam #4. The photo is facing downstream, with the dam top on the horizon. As the grain size fines downstream, the angle of repose changes; the cobbles can support a steeper angle, and the sandier berm a lesser slope. Access is easy on the downstream portion of the island, and is a little more difficult upstream; many islands in the Allegheny River are coarser grained on the upstream end, and fine downstream. The lithological makeup of the cobbles and pebbles is similar to that in figures 28 and 29. Figure 20 shows a sandy berm (with a small

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IV. Results and Discussion

A. Data Analysis C. Preservation The data from each 1/10th mile section Three different grades of riverbank of Pools 1, 2, 3, and 4 of the Allegheny River was preservation were created, with the idea of entered into a computer database, to be used in determining which sections were best preserved in conjunction with the GIS and ARCINFO mapping their natural state. There are no high banks which programs. The three major areas of inquiry using are still in their natural condition, (as perhaps would the geological dataset and the computer mapping have been seen before European settlement in programs are: the Pittsburgh area). All the high banks have been extensively modified, especially by railroad building 1) Describing which sections of the riverbank have activity over the past 150 years. Much material easy, moderate, and no access was imported as fill, to raise track beds above the 2) Determining which riverbank sections are the floodplain level. The Allegheny River had railroads best preserved, or which are closest to “pristine” along its banks and still does, although to a lesser condition, with minimum anthropogenic influence extent than when Pittsburgh was an industrial center. 3) Using datasets generated from sections one and The riverbank areas that are in their natural two to find riverbank sections that are worthy of state are those that have their materials reworked by restoration and/or other improvements flooding action. The low lying banks and berms are affected by periodic floods to a greater extent than B. Access the higher ones; since there is constant dynamic Three different grades of river access were change from erosion and deposition of material, generated : easy, moderate, and difficult/vertical these low sections represent the most “natural” access. Each of these grades was determined in the portions of the riverbank. field by estimating the difficulty one would have To determine which areas qualify as best landing a boat from the water onto the shoreline preserved, the height and frequency of flooding along in question, using a sixteen foot powerboat as the the Allegheny River has to be taken into account. The standard. In many areas, a smaller boat, such as a typical one-year (annual) flooding event has a water canoe, would be able to access a particular shoreline level height range of zero to 6 feet (US Army Corps of more easily than a larger powerboat. Conversely, Engineers, 1987). The two-year floods have average many of the shorelines that have an “easy” or water levels up to 9 feet above normal pool elevation, “moderate” access label could not be used by larger and the five-year flood has an average crest of 13 commercial craft. Some of the “vertical” or “no feet above pool. Any banks or berms below these access” cases are unusable by pleasure craft, but are elevations will have their materials and geometries suited more for large commercial freight carriers. reworked and changed due to the erosive and Several variables were used to determine depositional action of the water. Hence, these low- these access categories; examples include water lying portions of the banks can be interpreted as the depth as the shoreline is approached (for a sixteen closest to natural state. foot boat with a half foot loaded draft, and a jet type Another criteria used to determine outboard motor), the amount of restrictive vegetation, preservation is the amount of manmade material bank height and steepness, the width of the berm, present. If there is a smaller manmade material if present, and the competence of the berm or bank percentage in the bank or berm makeup, this can be material where one actually steps from the boat onto interpreted as existing closer to a natural state. the shore. Plate 1 is a map of Pools 1 through 4 on the Allegheny River that illustrates the three grades of The three grades of riverbank/berm general access. preservation and their criteria for selection are:

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Preservation Value Physical Condition Material Condition contiguous existing habitat would come into play Best - 0 - 6’ above pool, 100% natural when making a decision to restore. Moderate - 0 - 6’ above pool, 5 0 - 100% natural Figures 35 is a map of the Year 3 study area, Poor - 6 - 15’ above pool, 50 - 100% natural showing the riverbank sections that have the different grades of access. Figure 36 is the same area as figure These data operators were entered into the ARCINFO 35, with the riverbank sections that are candidates computer mapping program, and a map of the for preservation. Figure 37 shows the riverbank riverbank section’s preservation potentials were restoration potential for the same area and figure plotted (plate 5). 38 shows the floodplains that are effected by the one year flood, with a maximun height of six feet above D. Restoration pool level. All of the above maps were generated The restoration potential is contingent on from field data, and filtered using GIS and ARCINFO bank height (and potential floodplain affect) as well computer programs. Additional information gathered as soil composition. As depicted in the table below, this way can be applied to any portion of the study restoration values have been identified by physical area, at many scales. condition in relationship to the material condition of the banks. A third element, access to the site E. Riverbank Grain Size and Material Type Trends from both land-based communities and water-use Grain size attributes are important communities has not been considered in the current descriptive properties of riverbanks. Riverbank study. morphology can be predicted based on grain size measurements and material makeup. Grain size can Restoration Value Physical Condition Material Condition also predict river hydrological dynamics; erosional Best - 0 - 6’ above pool, 50-100% manmade cutbanks versus depositional sand bar banks. Moderate - 6 - 15’ above pool, 0-50% manmade This prediction holds true for natural or man-made Poor - 15 - 30’ above pool, 0-50% manmade materials. Grain size distribution trends in a riverbank also reflect watershed drainage, which depends on For example, a physical condition of 0 - 6’ land use, geology, and climatic factors. above pool places the bank in relationship to the Figures 41 - 44 are pie charts that show one-year flood pattern. Combined with a natural/ natural materials and grain sizes for Pools 1, 2, 3, manmade soil mix of 50% or greater manmade and 4 of the Allegheny River. Grain size trends for soils the restoration potential is high. Meaning man-made materials are not relevant, as they were that restoring the riverbanks to natural state is very not deposited through long-term natural geological possible as the physical and material conditions processes. In general, there is a trend of coarser are in place to support native plant materials. This grains along the upstream direction. This is true for is the condition for our best restoration scenario. most rivers and streams, especially if material was The moderate scenario, assumes the same bank added to the system, as seen in the Allegheny River, heights of 6 - 15’ above pool with 0 - 50% man-made resulting from glacial outwash deposit erosion and bank materials. The physical condition is in place transportation. Pool 1 has 78% mud, Pool 2, 48%, for a natural system restoration. The relatively good Pool 3, 47%, and Pool 4 at only 24%. The amount material condition of the banks can be amended. of sand increases upstream, and the cobble/gravel The lowest restoration value represents a physical amounts increase upstream, except for Pool 3. This condition of 15 - 30’ above pool with 0 - 50% is due to a smaller number of islands, as most of manmade material. Although there is still potential the cobble and gravel sized material is exposed for restoration, proximity to public access, use or along island shores. Figure 45 is a chart showing the

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average percentages of natural materials for all of the the Allegheny and Monongahela Rivers can be Allegheny River, Pools 1, 2, 3, and 4. illustrated. There is a greater concentration of man- Figures 45, 47, 48, and 49 are charts made materials (73% man-made and 27% natural) showing percentages of man-made riverbank in the Monongahela’s banks compared with the material in Pools 1, 2, 3, and 4 of the Allegheny Allegheny River (55% man-made, 45% natural). River. In general, there is an increase of historical Reasons for these differences will be discussed heavy industry (particularly steelmaking) along an below. The average grain size of natural materials upstream direction. The only major steelmakers in in the Monongahela River decreases upstream, in Pool 2 were Edgewater Steel, and Woodings-Verona contrast with the Allegheny River, where the grain Toolworks, both now defunct. Allegheny Ludlum Steel sizes of natural materials increases upstream. The is still active in pool 4. These riverbank industries can reason for these differences can be explained by the be correlated to the amount of slag found as bank extra glacial outwash material introduced in to the material; Pool 1 has only 3% slag, where Pools 2, 3, Allegheny River watershed at the end of the Ice Age. and 4 have 19%, 24%, and 45% respectively. Two major comparisons between the The amount of rubble and fill is fairly Allegheny and Monongahela Rivers will be presented: consistent over the study area, except in Pool 1, 1) using natural materials and morphology as a basis, where there was a greater amount of fill dumped and 2) the amount of industrial impact on both rivers. over time to increase land area in and near the City As stated earlier in this report, the materials of Pittsburgh. Pools 2, 3, and 4 have about the same seen in the riverbanks and bottoms differ greatly amount of rubble and fill, due to railroad construction between the Allegheny and Monongahela Rivers. along both riverbanks. The amount of concrete (used The materials found in the Monongahela river valleys for retaining walls and freight docks) is about the are all derived from the Monongahela drainage same for Pools 1, 2, and 3; there is a lesser amount basin, while the Allegheny has a large influx of exotic in Pool 4, as there is only one major dock (at the material, due to the last two glacial ice advances Allegheny Ludlum Steel Company). during the Pleistocene epoch. The lithological A general decrease of man-made bank differences in the natural materials in both rivers has materials can be traced along the upstream direction been discussed; igneous and metamorphic rocks (fig. 50 - 53). Pool 4 reverses the trend somewhat, that do not occur in the Allegheny River watershed again due to steelmaking activity there. Even though are present in the banks and berms, and these grains there is a slight increase of industrial activity in the show evidence of long transportation by water and upstream portions of the study area, the impact of ice, as they are well-rounded in shape. These exotic the City of Pittsburgh and other historical building cobbles and pebbles usually have a greater trend to activities downstream result in the trends seen in a more spherical shape (sphericity), as the nature the chart figures. Figure 54 is a chart with the total of these harder rocks does not allow easy breakage average amount of natural vs. man-made material along bedding planes. Large well-rounded cobbles percentages for the whole study area, with 45% of sandstone are sometimes (but rarely) seen in the natural bank materials and 55% man-made material. Monongahela River, but these sporadic clasts were The techniques used for grain size and material data probably transported by water from West Virginia. analysis can be applied down to the 1/10th mile bank There are only one or two layers of competent, section scale, if more detail is needed. massive sandstone that would act as a source rock for these grains, which explains their rarity in the F. Comparison: Allegheny and Monongahela Rivers Monongahela. Also, the distance of transportation is Using the material and grain size charts shorter than that of the Allegheny; longer transport from the previous year’s study, differences between distances result in more well-rounded grains. Most of

16 17 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

the natural bedrock in the Monongahela watershed is Allegheny and Monongahela Rivers is the amount and too incompetent to stand up to long river transport. type if industrial impact each river experienced. Most of the cobble and pebble sized clasts in the The main factor influencing industrial site Monongahela have poor sphericity, as the local rocks placement in the Pittsburgh area is the proximity break easily along their bedding planes, resulting in to coal resources, especially those mined from the flatter grains, that are “pancake” shaped. ten-foot thick Pittsburgh Seam. The Pittsburgh Seam Another major difference in natural materials is present in the Monongahela valley, but mostly between the Allegheny and Monongahela absent from the Allegheny valley. Since the amount Rivers, apart from lithology, is the amount of of coal needed for the steelmaking industry is large, material in each river valley, usually referred to as and transportation costs are high for such a great the sediment load. There is a limit to how much amount of bulk, most of the steelmaking activity was sediment a river can carry; when that limit is reached, built in the Monongahela valley. Figure 56 is a map the morphology of the river changes greatly. A river of Allegheny County, showing where the Pittsburgh that has a small sediment load has one channel in Seam occurs. Northward, in the Allegheny valley, its valley; as the sediment load is increased, islands this seam has been eroded away. Except for the start to form, dividing the channel somewhat. If Upper Freeport Coal, (which is much thinner than there is even more sediment load, the river changes the Pittsburgh Coal) there are comparatively fewer its shape to a braided stream, with amastomizing coal resources available in the Allegheny valley, channels, separated by many small islands. Many compared with the Monongahela valley. Hence, river deltas have this shape. Generally, for a given the impact of industry is less in the Allegheny than amount of sedimentary load, rivers with smaller the Monongahela. Present day evidence for this gradients will tend to have a braided shape, due are fewer slag piles, abandoned barge docks, etc. to the sediment load dropping out of the water, During the height of industrial activity in Pittsburgh, from lower water velocity. The upper reaches of the there was a much greater amount of coal shipped on Allegheny (outside of the study area) tend more to the Monongahela. Figure 57, which is an old chart a true braided morphology, as there is less water to showing river transportation tonnage broken down remove the sediments present. A good example of by each commodity (in 1925) clearly indicate where this can be seen in Port Allegany, PA. the greater amount of coal was shipped. Conversely, The Allegheny River has a slightly steeper the Allegheny moved a larger tonnage of gravel, for gradient than the Monongahela, but the sediment reasons already explained. load is much greater, from the influx of glacial alluvium. The load is greater than the river can easily carry, and island formation results. Lithology and the amount of natural materials are different between the Allegheny and Monongahela Rivers; this is why one sees no large islands or gravel banks in the Monongahela River. Figure 38 shows four cross-sections of the Allegheny River; note the large amount of glacially derived alluvium in each case. Figure 55 is a map of the gravel resources in Pennsylvania, showing the glaciated areas, along with major streams that carry glacial outwash. A second major comparison between the

16 17 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

V. References

Adamson, J.H., Graham, J.B., and Klein, N.H., 1949, Geologists, J.A. Harper, ed., p. 28-37. Ground Water Resources of the Valley Fill Deposits of Allegheny County, Pennsylvania. Pennsylvania Wagner, W.R., 1970, Geology of the Pittsburgh Area, Geological Survey (4thSeries) Bulletin W8. Pennsylvania Geological Survey General Geology Report G-59, 145 pp. Bayley, P. B. (1995). Understanding large river- floodplain ecosystems. BioScience, 45: 15 158.

Bloom, A.L. (1978). Geomorphology. Prentice-Hall, Inc.: Englewood Cliffs, New Jersey.

Boggs, S, Jr.(1987). Principles of Sedimentology and Stratigraphy. Merrill Publishing Company: Columbus.

Craft, J.L., 1979, Quality of Gravel Resources in Northwestern Pennsylvania. Pennsylvania Geological Survey (4th Series) Information Circular 86.

Johnson, M.E., 1929, Geology of the Pittsburgh Quadrangle, Pennsylvania Geological Survey, 4th Series, Atlas A-27.

Junk, W.J., Bayley, P.B., Sparks, R.E. (1989). The flood pulse in river-floodplain systems. Canadian Special Publication Fish. Aquat. Sci. 106: 110-127.

Leighton, H., 1926, The Geology of Pittsburgh and its Environs: A Popular Account of the General Geological Features of the Region, Annals of the Carnegie Museum, v.XVII, Part I, p. 91-166.

Leighton, H., 1946, Guidebook to the Geology of Pittsburgh, Pennsylvania Geological Survey, 4th Series, Bulletin G-17.

Leopold, L.B., Wolman M.G., Miller, J.P. (1964). Fluvial Processes in Geomorphology. W.H. Freeman, San Francisco.

Marine, J.T., and Donahue, J., 2000, Terrace Deposits Associated with Lake Monongahela, in Guidebook, 65th Annual Field Conference of Pennsylvania

18 19 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

VI. Appendix A Figures

18 19 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

������������� ��� ������� ���� ���� ������� ���� ������ ���� �������� �� ���������� �� ���� �������� �������� ���� ���� ��������� ��� ���� ���� ���������� ���� ���� ����� ���� ���� �������� ����� ����� ���� ���� �������� ���� ����� ���� ���� ������� ����������� ���� ���� �� � ����� ������������� � � � � �

� ���� �

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�� ���� ����� � � �������� �� ���� ������ ���� ����� �������� ���� ���� ���������� ���� ����� ���� ����� ���� �������� ����� ���� ����

Fig. 1. Simplified geological time scale, showing the relationships between eras, periods, and epochs. The rocks of the Pittsburgh area were deposited mainly during the Late Pennsylvanian. Time is shown in millions of years.

20 21 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 2. Expanded portion of the Pennsylvanian Period

20 21 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 3. Bedrock layers as currently seen from the Allegheny River

Fig. 4. Paleogeographic map of Pennsylvania, 300 millions years ago

22 23 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 5. Downtown Pittsburgh

Fig. 6. Terrace deposits and abandoned loops in the Pittsburgh area

22 23 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 7. Deposits in Allegheny County

Fig. 8. Pre-glacial river drainage of Western Pennsyl- Fig. 9. Present drainage patterns in Western Pennsyl- vania vania

24 25 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 10. Vertical riverbank, consolidated manmade Fig. 13. Natural bedrock materials

Fig. 11. Vertical riverbank, consolidated manmade Fig. 14. Edge access difficult materials

Fig. 12. Vertical riverbank, consolidated manmade Fig. 15. Stablized bank materials

24 25 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 16. Moderate to difficult access Fig. 19. Coarse material, shallow angled berm

Fig. 17. Wide berm Fig. 20. Easy access, natural setting, sandy berm

Fig. 18. Ideal accessibility Fig. 21. Easy access, nautral setting

26 27 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 22. Easy acces, non-aesthetically pleasing Fig. 25. Wreck

Fig. 23. Easy access, non-aesthetically pleasing Fig. 26. Mix of man-made materials

Fig. 24. Water level structure Fig. 27. Large boulder

26 27 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 28. Large gravel bank

Fig. 29. Large gravel bank Fig. 31. Introduced material, bank

Fig. 30. Introduced material, berm Fig. 32. Berm gradation

28 29 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 33. 100% mud, poor access Fig. 34. Small stream delta

28 29 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

NATURAL MATERIALS: ALLEGHENY POOL 1

SOIL GRAVEL SAND 0% 14% 8%

GRAVEL MUD SAND SOIL

MUD 78%

Fig. 41

NATURAL MATERIALS: ALLEGHENY POOL 2

BEDROCK 1% BOULDERS 14%

BEDROCK COBBLES 13% BOULDERS MUD COBBLES 48% GRAVEL

GRAVEL SAND 9% MUD

SAND 15%

Fig. 42

NATURAL MATERIALS: ALLEGHENY POOL 3

BED ROCK BOULDERS 1% 8% COBBLES 5% SAND GRAVEL BED ROCK 36% 3% BOULDERS COBBLES GRAVEL MUD SAND MUD 47%

Fig. 43

30 31 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

NATURAL MATERIALS: ALLEGHENY POOL 4

BEDROCK 3% BOLDERS 6% COBBLES 7% BEDROCK GRAVEL BOLDERS 12% SAND COBBLES 48% GRAVEL MUD SAND

MUD 24%

Fig. 44

NATURAL MATERIALS: TOTAL ALLEGHENY RIVER

SAND SAND MUD 37% BEDROCK 43% BOULDERS COBBLES GRAVEL BEDROCK MUD 1%

GRAVEL BOULDERS 7% 6% COBBLES 6%

Fig. 45

STONE BLOCK STONE 2% 0% STEEL 1% WOOD SLAG 4% 3%

CONCRETE 24% WOOD CONCRETE RUBBLE/FILL SLAG STEEL RUBBLE/FILL 66% STONE STONE MAN-MADE MATERIALS: ALLEGHENYBLOCK POOL 1

Fig. 46

30 31 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

MAN-MADE MATERIALS: ALLEGHENY POOL 2

WOOD STONE BLOCK 3% 12% STEEL 5% CONCRETE 26% WOOD CONCRETE GABION SLAG RUBBLE/FILL 19% GABION SLAG 0% STEEL STONE BLOCK

RUBBLE/FILL 35%

Fig. 47

MAN-MADE MATERIALS: ALLEGHENY POOL 3

WOOD 1% STONE BLOCK STEEL 9% 5%

OTHER STONE BLOCK SLAG 1% 24% OTHER RUBBLE/FILL CONCRETE RUBBLE/FILL SLAG 39% STEEL WOOD

CONCRETE 21%

Fig. 48

MAN-MADE MATERIALS: ALLEGHENY POOL 4

WOOD 7% CONCRETE STONE BLOCK OTHER 6% 2% 2% STEEL 5% CONCRETE OTHER RUBBLE/FILL RUBBLE/FILL 33% SLAG STEEL STONE BLOCK WOOD SLAG 45%

Fig. 49

32 33 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

NATURAL AND MAN-MADE: ALLEGHENY POOL 1

NATURAL 24%

NATURAL MAN-MADE

MAN-MADE 76%

Fig. 50

NATURAL AND MAN-MADE MATERIALS: ALLEGHENY POOL 2

NATURAL 43% NATURAL MAN-MADE MAN-MADE 57%

Fig. 51

MAN-MADE AND NATURAL MATERIALS: ALLEGHENY POOL 3

NATURAL 32%

MAN-MADE NATURAL

MAN-MADE 68%

Fig. 52

32 33 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

NATURAL AND MAN-MADE MATERIALS: ALLEGHENY POOL 4

MAN-MADE NATURAL 48% NATURAL 52% MAN-MADE

Fig. 53

NATURAL AND MAN-MADE MATERIALS: TOTAL ALLEGHENY RIVER

NATURAL 45% MAN-MADE MAN-MADE 55% NATURAL

Fig. 54

34 35 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 55. Map of the gravel resources in Pennsylvania, showing glaciated areas, along with major streams that carry glacial outwash

Fig. 56. Map of Allegheny County, showing where the Pittsburgh Seam occurs

34 35 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

Fig. 57. Chart showing river transportation tonnage broken down by each commodity

36 37 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002

VI. Appendix B

Figure 35. River Access Map Figure 36. River Preservation Potential Map Figure 37. River Restoration Potential Map Figure 38. Floodplain Map

36 37 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002 pihsnwoTnosirraH egdi r hguoroBmulP p h n i gu e h kc s o r n a r o w B B oTn m h u w g t a u n F o e r r o a T B pihsn r e la p e i w h e h o d g p s i D T g u n h t n i o e s s w l r r n a o a p o d E T w S B gni oTrezarF k rp c h i g w S u s o e r h o slliHnne C B h P gu f o p i o r pihsnwoTree h y t o s il h B n a g t w p u i n h o o c a g o r i T n u o n m r o or u B r k a l e o a li M p m V B i r O h h a c Dtse s r H n u 1 h w p i x C h o h o g W T a s n r u n o a a w e ro h n a w l H g talP a o B B i u O T d o r n I h o g B uo g r r o u b B s l ni e p k li a h W p C ih l a l r s x a a h n H o g w w o u O General Access n F i T o r p s o 2002 River Access A B hgr g u p r i b u h s h a b t s r t s g pihsn i n a p u r P w o H r a f o h o o p T O ih S B ytiC w o s T n w d a h o n n g t a T u lh pi E o n r h ci o s o tpmaH n yradnuoBlapicinuM R B woTrelahS maDdnakcoL h el g u a o v l r ygolordyH lMi oB p ih e vr s n e s w e o R T pihs s n s pi e w h ld h o g s r T na n u en b w C s i o tt c P T i Mfon w P s ei s f h o o g V u gnidnaL/sseccAetaredoM R y t ti o s sseccer A sseccer w ro e o C T W B gnidnaL/sseccAysaE e h u g sseccAoN/lacitreV v s u k e o l c l r o e o p i R B B hs h s h h n g e n n g g o h n u e h s o v u u g w t o o t g l K r f o u o A h o m u r c r a o d o a g h a T i o v o n r r r o r B M r g s e A B e o o g e C B o u f d B H B n h I B d o w o p r g i a o o g t u r o h r n o S h h s B W B u n r o sseccAknaB g b g n e v o u n u B A B w r p o i o h r o o t r h p p r h o h T i i o s o g T B h h B n o u w s i s o s w k h n n ro ra o m w w O T E B o o P k T T p i c n l i l y h l u s e a d k l Fig. 35. Riv b l n l h i e n i v s w n a K r e r o n aM F N T e K Hills Borough Sewickley Glenfield Borough 38 39 Aleppo Township Haysville Borough Robinson Township Sewickley Heights Borough Coraopolis Borough Bell Acres Borough 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002 seliM yradnuoBlapicinuM 3215.00 3noitavreserP 2noitavreserP 1noitavreserP maDdnakcoL pihsnwoTnosirraH Preservation Potential egdir h p h n i g g e h u u kc s o o r n r a r o o w B B B o T m n m u h l u w g t P a u n F o e r r o a T B pihs n e r la p e i w h e h o d g pi s D T g u n h n t i o e s l s w r r n a a o p o d E T w S B g o ni T k r r c h i p e g w S z u s o a e r rF h o slliHnne C B h P gu f p o i o r p h y i t o s il h h n B s g a t w n u p i n h o o w c a g o r i T o n u o n r m T o o u B r r k a r l e o a lih M e m p V B i r O e h a c D s r H t n u se h w p i x o h C h o g W T a s n u r n o a a w ro h n a w lB H g ai o B u O T d o r n I h o g B uo g r r u o bs B le ni p k li a h W p C i l a l h r s x a a h nw H g o w u o O n F i T o r p s o A B hgr u g pi r b u h s a h b t s 2002raeYtcejorP:ygoloeGN2R3 r t s g i p n a i p u P r h w o H a r f s o h o o n O T p i S B y w alentiotvation Psereer Pr Psereer alentiotvation h t i o s T C n w d a h o n g n t a T u l p E i o h n r h c o i o s tp n R B wo m aH TrelahS h el g u a o v l r li o M B p ih e vr s n e s w e o R T pihs s n s p e i w l h h o d g s r T n n u a e b w C n s i o t c ti P T M P w s f e f s h i o o o g V n u R t y ti o s w ro e o C T W B Fig. 36. Riv e h u g sk u ev Bell Boro McKees Roc Borough Avalon Borough Crafton Borough Ben Avon Heights Borough 38 Ingram Borough 39 Stowe Township Bradford Woods Borough Ben Avon Borough Thornburg Borough Emsworth Borough Franklin Park Borough 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002 l s a e y l i i r t a M 6 . n d 3 n e u t m 3 2 1 o a o n n n 7 B . D o o o l P 2 i i i t t t a d a a a p n n i r r r a c o o o o i t t t 8 i . k n s s s t 1 c u e e e a o R R R r M L o 9 . t 0 s 5 4 p . e i h 0 s n R 0 w o T n o s i r r a H e g d i r h p h n i g g e h u u k s o c o r n r a r o o w B B B o T m n m u h l u w g t P a u n F o e r r o a T B p i h s e n r l p e i w a h e h o d g p s i D g T u n h t n i o e s s w r r l n a o p o a d w E T S B g o n T i k r r c h i p e g w S z u s o a e r r h o F C B s l l i H n n e h P g f u p o i o r p h y i t o s i h h l B n s g a t n w u p i h n o o w c a g o r i T o n u o n m r T o o B u r r k a r l e o a l M e i m V B p i r O e h h a c D r s H t u n s h w p e i C x o h h o g W a T s n r u n o a a w r h a n w l o H g a o B B i u O T d o r n I h o g B u g o r r u o b B s l n e i k p l i a h W C p i l a l h r s x a h a n H o g w w u o O F n i T o r p s o A B h g r g u p r i 2 b u h s a h b t s r t s g p i n 0 i a p u r P h w o H a r f s o 0 h o o n O T p S B i w y h t 2 i o s T C n r d w a h n o n g t a T a u l p E i o h n r h c o e i o s t R n B p w m Y o a T H t r e l c a h e S h j e g l u a o v o l r l i o r M B p i P e h v s r n : e s w e y o R T g p i h o s s l n s p e i w h l o h o d g s r T n n u a e e b w n C s i o t c t P T i G M P w s f e f s i h o o o g V n u R y t N t o i s w r e o C o 2 T W B Fig. 37. River Restoration Potential Restoration Fig. 37. River R e h u g 3 v s u k e o l c l r o p e o i R B B h h s s h h n g e n n g g h o n u e h s o u v u g w t o o t l g K f o r o u h A o m r a c u r o a d o g h a T i v o o r r n r o r M B g r s e e o A B o g e C B o f u d B H B n h I B d o w o p r g i a o o g t r o u

40 h 41 r n o S h B W B s h u n r o g b n g e v o u n u B A B w r o h o o r o t r r h o h T o o g T B B o u w i o s k h r r m o O a E B P n i l k n a r F 3R2N Riverbank Geology, Phase 3 - 2002 3R2N Riverbank Geology, Phase 3 - 2002 s y n r i e l i a a d M l n 3 p u m o a d B D n o l i d a a o l n 2 p l i p a c d F i k o n c o u l o F M L 1 5 . p i 0 h s n 0 w o T n o s i r r a H e g d i r h p h i n g g e h u u k s o c o r n r a r o o w B B B o T m n m u h l u w g t P a u n F o e r r o a T B p i h s n e r l p e i w a h e h o d g p s i D T g u n h n t i o e s l s w r r n a a o p o d E T w S B g o n T i k r r c h i p e g w S z u s o a e r r h o F s C B l l i H n n e h P g f u p o i o r p h y i t o s i h h l n B s g a t w n u p i h n o o w c a g o r i T o n u o n r m T o o B u r r k a r l e o a l M e i m p V B i r O e h h a c D s r H t u n s h w p e i x C o h h o g W T a s n u r n o a a w r h n a w l o H g a o B B i u O T d o r n I h o g B u g o r r u o b B s l n e i p k l i a h W p C i l a h l r s x a a h n H g o w w u o O n F i T o r p s o A B h g r g u p r i b u h s a h b t s 2 r t s g i p n a i p u r P h w o 0 H a r f s o h o o n O T p 0 i S B y w h t i o s 2 T C n w d a h r o n g n t a T u l p E i a o h n r h c o i o s t e n R B p w m o Y a T H r t e l a c h S h e e g l j u a o v l r l o i o r M B p i e P h v s r n e : s w e o y R T g p i h o s s l n s p e i w l h h o o d g s r T n n u a e e b w C n s i o t c t P i T G M P w s f e f s h i o o o g V n u R t y N t o s w i r e o C o 2 T W B Fig. 38. Floodplains R e h u g 3 v s u k e o l c l r o p e o i R B B h h s s h h n g e n n g g h o n u e h s o u u v g t w o o t g l K o r f u o h A o m r u c a r o d o a g h a T v o i o n r r r o r M B r g s e A B e o o g C B e o f u d B H B n h I B d o w o r 40 g 41 a o o g t u r o r n o S h h B W B u n r o g b g e v o u n u B A B r o o h r o t r r h o h o o g T B B u w o s k r r m o a E B P n i l k n a r F