S.R. 4031, SECTION FVR OVER BEAVER RUN SEGMENT 0170, OFFSET 6093 EAST NANTMEAL TOWNSHIP, CHESTER CO. ENGINEERING DISTRICT 6-0

Transcription

1 S.R. 4031, SECTION FVR OVER BEAVER RUN SEGMENT 0170, OFFSET 6093 EAST NANTMEAL TOWNSHIP, CHESTER CO. ENGINEERING DISTRICT 6-0 HYDROLOGIC & HYDRAULIC STUDY REPORT OCTOBER 2007 Prepared For: Prepared By: Pennsylvania Department of Transportation Engineering District Geerdes Boulevard King of Prussia, PA WHITNEY, BAILEY, COX & MAGNANI, LLC 355 N. 21 st Street, Suite 100 Camp Hill, PA Voice: Fax:

2 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6093 FAIRVIEW ROAD OVER BEAVER RUN EAST NANTMEAL TOWNSHIP, CHESTER CO. TABLE OF CONTENTS

3 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County TABLE OF CONTENTS I. Scope of Study... 1 II. Site Data... 1 III. Hydrologic Analysis... 2 IV. Hydraulic Analysis... 4 V. Scour Analysis... 8 VI. Conclusions and Recommendations... 8 VII. Summary Data Sheet... 9 VIII. Hydrologic and Hydraulic Report Checklist LIST OF FIGURES Figure No. 1: FEMA Model vs. Existing Conditions HEC-RAS Model... 7 LIST OF TABLES Table No. 1: S.R FVR Basin Data... 3 Table No. 2: S.R FVR Hydrology Data... 3 Table No. 3: Existing and Proposed Water Surface Elevations Upstream of Bridge (HEC-RAS SECTION 8)... 6 Table No. 4: FEMA Existing and Proposed Water Surface Elevations Upstream of Bridge (HEC-RAS SECTION 8)... 7 WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 TOC-1

4 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County LIST OF APPENDICES Appendix A : Photographic Documentation Appendix B : Hydrologic Computations Appendix C : Water-Surface Profiles and Summary Tables Appendix D : Cross-Section Plots Appendix E : HEC-RAS Models Appendix "F": Graphs Appendix C-1 : Existing Conditions Appendix C-2 : Proposed Conditions Appendix D-1 : Existing Conditions Appendix D-2 : Proposed Conditions (Bridge Only) Appendix E-1 : Existing Conditions (Detailed Output) Appendix G : HEC-23 Computations (Scour Countermeasures) Appendix E-2 : Proposed Conditions (Detailed Output) Appendix F-1 : Flood Frequency Analysis Graph Appendix F-2 : Stage Discharge Graph Appendix H : Floodplain Map Proposed S.R FVR Roadway Plan & Profile Proposed S.R FVR Bridge Plan Appendix I : Flood Insurance Study Township of East Nantmeal Community ID WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 TOC-2

5 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County I. SCOPE OF STUDY The purpose of this study is to develop the hydrologic and hydraulic analysis required for the replacement structure for the existing Fairview Road Bridge (S.R. 4031) over Beaver Run in East Nantmeal Township, Chester County. II. SITE DATA This route is classified as a Minor Rural Collector roadway and has a 10-year design storm frequency. The existing deteriorated structure is a two-span concrete slab bridge constructed in 1923 (Bavenson s Bridge, No. 286). The existing bridge has a total clear span of 40 feet, a curb-to-curb width of feet and is skewed at approximately 78 degrees. The minimum underclearance for the existing structure is 5.89 feet. It is proposed to replace the existing two-span bridge with a 46.5-ft single span prestressed concrete spread box beam bridge. The FEMA study for the stream indicates that the existing structure is inundated for the 50-year storm event (See FEMA Study Appendix I). The replacement structure should not increase the upstream 2-, 10-, 25-, 50-, 100- and 200- year water surface elevations. The replacement bridge has an estimated construction cost of $432,790 for the project let year of The bridge crossing is located 300 feet west of the intersection of Fairview Road and State Route 100 and is 1.14 miles east of Nantmeal Village, and is 6,000 feet upstream from the nearest stream crossing in Nantmeal Village. A small wooden footbridge is located 170 feet downstream and does not create any significant backwater. There are no additional stream crossings that would influence the hydraulic analysis. The Vicinity and Location Maps for the site are included in Appendix B. The stream channel at the bridge has a gravel and silt bottom that varies from 15 to 25 feet in width. Stream flow for Beaver Run is continuous. The stream banks are densely vegetated with brush and trees upstream of the bridge. Approximately 100 feet upstream of the bridge, there is a constriction in the floodplain formed by the roadway grading in the left overbank and by mounds of fill in the right overbank. The existing channel upstream of the bridge parallels Fairview Road, makes a 60-degree bend through the bridge, and then follows the alignment of Route 100. This flow pattern causes the existing three foot wide pier to act as a debris collector creating flow obstructions beneath the bridge. This flow obstruction increases the flow velocity beneath the bridge creating a scour hole in front of the east abutment. Downstream of the crossing, the floodplain is predominately meadow with the stream banks covered with grass as Beaver Run has a 20 degree bend in its alignment. The stream within the project area is classified as a High Quality-Trout Stocked Fishery, Migratory WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 Page 1

6 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County Fishery (HQ-TSF, MF) under Title 25, Environmental Protection, Chapter 93, Water Quality Standards. The east roadway approach to the bridge is lower than the bridge itself (See Appendix A, Photo 11) and conveys the flow that bypasses the bridge during high flood stages. There are no accounts of flooding by local residents; however, the hydraulic model developed in Section IV of this report indicates that the right overbank (looking downstream has a flood frequency average of 5 years. There are two structures in the east overbank adjacent to the road, a private residence (1817 Pottstown Pike) and a barn located south and north of the bridge, respectively. The grading for the structures obstructs much of the flow overtopping the road. A farm pond is located south of the bridge in the east overbank. It is outside of the 100- year floodplain and had no impact on the computations. The west overbank downstream of the bridge is a steeply graded floodplain in contrast to the east overbank which is flat and is frequently inundated. A driveway for a house elevated above the floodplain (2129 Fairview Road) is located west of the bridge. The stream has been studied by FEMA in the vicinity of Fairview Road in the Flood Insurance Study for Chester County, Pennsylvania dated March East Nantmeal Township has a Community ID of Field reconnaissance photographs of the bridge and stream from the April 2006 site visit are contained in Appendix A. Line, Grade & Typical Section was verbally approved at the Pro Team Review Meeting on August 13, III. HYDROLOGIC ANALYSIS The watershed hydrology was computed using the methods in Design Manual Part 2 (DM- 2), Section based on the basin data found in Table 1. The basin data used in the hydrologic analysis is tabulated in Table No. 1. WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 Page 2

7 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County TABLE NO. 1: S.R FVR BASIN DATA BASIN PARAMETER MEASURED OR CALCULATED DATA 1. Drainage area 2.98 square miles 2. Latitude N 40 o 08' 00" 3. Longitude W 75 o 42' 30" 4. Region PA Flood Frequency Region 1 5. Limestone None 6. Dolomite None 7. Urbanization 4% 8. Risk Factor 0.3 (Minor Damage) 9. Wood Factor None 10. Storage Effects No lakes, reservoirs or swamps 11. Carbonate Rocks None The DM-2 discharges are compared with the Chester County FEMA Flood Insurance Study (FIS) discharges in Table 2. The FEMA Flood Insurance Study hydrology was developed using PSU-III. TABLE NO. 2: S.R FVR HYDROLOGY DATA STORM FREQUENCY (YRS) DM-2 FLOWS (CFS) FEMA FIS FLOWS (CFS) , ,413 1, ,698 1, , ,890 The table indicates that the DM-2 discharges were slightly higher than the Flood Insurance Study discharges. Therefore, the DM-2 discharges were used in the hydraulic modeling for the crossing. WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 Page 3

8 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County IV. HYDRAULIC ANALYSIS A. Existing Conditions HEC-RAS version (3.0.1) was used for the hydraulic analysis. A HEC-RAS model was developed for the stream crossing. Twelve (12) cross-sections were field surveyed in April 2006 and are oriented looking downstream from left to right. The modeling was begun 305 feet downstream of the bridge and extended to 379 feet upstream for a total study reach of 684 feet. The cross-section locations are shown on the floodplain map included Appendix H. The following Manning 'n' roughness coefficients were used in the modeling of the stream: Land Use Manning's 'n' Factor Stream Channel 0.03 Grass/Field 0.08 Woods 0.12 Brush 0.10 The existing expansion and contraction coefficients for the stream were set to be 0.1 and 0.3, respectively. The expansion and contraction coefficients at the bridge were set to be 0.3 and 0.5, respectively. Ineffective flow areas in the vicinity of the bridge were delineated by 1:1 contraction ratio upstream and a 4:1 expansion ratio downstream (see floodplain map, Appendix H). These ineffective flow areas were input into the model as levees. The buildings adjacent to the road also created ineffective flow areas outside the zone of ineffective flow created by the bridge. These ineffective flow areas were input into the model by setting the Manning s n value to be The water surface profiles and summary tables are in Appendix C; cross-section plots in Appendix D; and existing condition HEC-RAS input for the model is contained in Appendix E. The existing 100-year floodplain elevation is feet. The existing flood elevations are tabulated in Table 3. The hydraulic analysis indicates that even though the right overbank is lower than the bridge, the area in the immediate vicinity of the bridge structure conveys the flood flow. This is due to the building obstructions in the right overbank. Most of the backwater is not created by the bridge itself but by a constriction in the 100-year floodplain at cross-sections 8 and 9. WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 Page 4

9 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County The private residence located on the upstream side of the bridge is flooded by the 100-year storm. The lowest point where water can enter into the residence located at 1817 Pottstown Pike is at an elevation of feet. The 100 year flood elevation is , and the house is 2 feet below the existing floodplain. It is estimated that the residence will food on an average 25-year frequency (See Appendix E). The outbuilding, located on the north side of the roadway and downstream of the bridge, has a building corner at elevation The 100-year flood elevation downstream of the bridge is at which inundates the structure by 0.87 feet. This structure would be inundated on a 10-year frequency. B. Proposed Conditions It is proposed to replace the existing bridge with a 45-foot clear span prestressed concrete spread box beam bridge having an out-to-out width of The proposed bridge will have a low chord elevation of and will have a 5.87-ft underclearance with the stream channel. As part of the bridge replacement, the proposed roadway profile will be raised by approximately 1 foot in the vicinity of the crossing in order to accommodate the design speed of the road and to improve the hydraulic opening. The proposed horizontal alignment of the road will remain the same as the existing alignment. Plan and section views of the proposed structure are included in Appendix H. The proposed bridge will have a structural depth of 2-1. The replacement structure will use Alternate PA Type 10M Barrier which has a height of 3-6. The existing HEC-RAS model, including ineffective flow areas was maintained as part of the proposed condition bridge model. The roadway elevations in the hydraulic model were adjusted to match the centerline profile. The N factor for the channel at the bridge was maintained at to account for the smooth walls of the proposed bridge structure. The water surface profiles and cross-section plots for the proposed condition model are in Appendix C-3 and D-2, respectively. Results of the hydraulic analysis indicate a decrease of 1.38 feet in the 100-year water surface elevation upstream of the bridge. The existing overtopping frequency of the approach roadway will be reduced from 50 years to 120 years for the proposed conditions. WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 Page 5

10 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County STORM FREQ. (YRS) TABLE NO. 3: EXISTING AND PROPOSED WATER-SURFACE ELEVATIONS UPSTREAM OF BRIDGE (HEC-RAS SECTION #8) EXISTING WATER SURFACE ELEV. (FT) EXISTING ROAD CLEARANCE (FT)* PROPOSED WATER SURFACE ELEV. (FT) PROPOSED ROAD CLEARANCE (FT)** DIFFERENCE BETWEEN PROPOSED & EXISTING WATER SURFACE ELEVATION (FT)*** * Existing low chord elevation = El ; (-) denotes depth of inundation ** Proposed low chord elevation = El ; (-) denotes depth of inundation *** (-) denotes proposed flood elevation lower than existing condition C. Comparison to FIS Analysis The Flood Insurance Study floodplain model input was obtained from FEMA and input into HEC-RAS. The flood elevations computed from the FEMA model were compared to the elevations computed from the existing conditions model developed from the field survey data. The comparison of the 100-year flood elevations are shown in Figure 1. The results indicate the existing conditions model has slightly higher flood elevations than the FEMA model below the bridge but lower elevations immediately above the bridge. This is due to the existing conditions model being more detailed than the FEMA model and accounting for the constriction in the floodplain. The elevations then become slightly higher 200 feet upstream of the bridge. WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 Page 6

11 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County FIGURE NO. 1: FEMA MODEL VS. EXISTING CONDITIONS HEC-RAS MODEL TABLE NO. 4: FEMA EXISTING AND PROPOSED WATER-SURFACE ELEVATIONS UPSTREAM OF BRIDGE (SECTION #8) STORM FREQ. (YRS) EXISTING FEMA ELEVATION (FT) REVISED FEMA ELEVATION (FT) DIFFERENCE BETWEEN EXISTING & REVISED (FT) PROPOSED FEMA ELEVATION (FT) DIFFERENCE BETWEEN EXISTING & PROPOSED (FT) WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 Page 7

12 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R Section FVR Segment 0170, Offset 6093 East Nantmeal Township, Chester County V. SCOUR ANALYSIS A. Geotechnical Investigation (Pending Core Borings) B. Scour Countermeasures (Pending Geotechnical Investigation) VI. CONCLUSIONS AND RECOMMENDATIONS The project is the replacement of the existing two span concrete slab bridge carrying S.R Fairview Road over Beaver Run in East Nantmeal Township. The road is classified as a Minor Rural Collector which requires that the bridge over Beaver Run is designed for a 10-year storm event. The proposed structure will be a single span prestressed concrete spread box beam bridge with a hydraulic opening width of 45 feet, an increase of 5 feet from the existing bridge hydraulic opening. The proposed bridge will be more hydraulically efficient than the existing structure since the new bridge will span Beaver Run without a pier. The surrounding area is prone to flooding, and the proposed bridge will not increase the existing 100-year flood elevation in compliance with state and federal floodplain guidelines. The HEC-RAS analysis produced a lower 100-year flood elevation than the FIS study, and it is recommended that the community file for a conditional letter of map revision from FEMA. The existing overtopping frequency of the approach roadway will be reduced from 50 years to 120 years for the proposed conditions. P:\2005\ \Design\Permitting\H&H Report\H&H Report_4031.REV1.doc WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors October 2007 Page 8

13 Location Data County Location - U.S.G.S. Map Latitude Longitude Present ADT (2009) Summary Data Sheet Chester Pottstown N40 o 08'00" Municipality State Route - Section Station W75 o 42'30" Segment/Offset 1,067 Future ADT (2029) East Nantmeal S.R FVR /6093 1,465 Channel Data Stream Name Stream Slope Normal Stream Flow Depth Stream Bed Elevation at Inlet Stream Bed Elev. Exact Dist. ~500' upstream Elevation Average Stream Channel Depth Beaver Run ft/ft 1.5' ' ' Side Slope (looking Left: downstream) Right: Type of Channel Average Top Width Average Bottom Width Stream Bed Elev. Exact Dist. ~500' downstream Elevation High Water Elev. and Date 2:1 2:1 Sand 25' 17' 300' N/A Hydrology Hydrology Method Used PSU-IV River Basin (USACE) Delaware Project Drainage Area 2.98 Sq. Mi. Q10 (CFS) 851 Q25 (CFS) Q50 (CFS) Q100 (CFS) 1,148 1,413 1,698 Q200 (CFS) 2,042 FEMA (if applicable) Comm. No Drainage Area 2.89 Sq. Mi. Q10 (CFS) 860 Q25 (CFS) --- Q50 (CFS) 1,290 Q100 (CFS) 1,500 Hydraulics EXISTING STRUCTURE PROPOSED STRUCTURE Bridge Type Reinforced Slab Bridge Type Spread Box Beam Clear Span - Centerline 20' Clear Span - Centerline 46' Clear Span - Normal Skew 20' 78 o Clear Span - Normal Skew 45' 78 o Minimum Underclearance 5.89' Minimum Underclearance 5.87' Length of Channel Impacted 30' Length of Channel Impacted 30' Number of Spans 2 Number of Spans 1 Low Chord Elevation Low Chord Elevation Hydraulic Method Used HEC-RAS (3.0.1) Hydraulic Method Used HEC-RAS (3.0.1) Return Period* Q WSE** Velocity Return Period* Q WSE Velocity Overtopping Overtopping *Indicate Design Return Period with a at the appropriate year. **Water surface elevation at upstream face of bridge.(cross Section 8) 7-Dec-07 PAGE 9

14 Appendix D - Hydrologic and Hydraulic Report Checklist Publication 13M (DM-2) Change #1-2/06 APPENDIX D HYDROLIGIC AND HYDRAULIC REPORT CHECKLIST PAGE 10

15 (3) HYDROLOGIC AND HYDRAULIC REPORT CHECKLIST Project: S.R FVR, Chester County Subject: S.R FVR over Beaver Run Date: Reviewer(s): James Kramperth, PE & Jennifer Gutshall, PE District: PennDOT District 6-0 ITEM PRESENT DESCRIPTION YES NO N/A A.1. LOCATION MAP X Acceptable forms (check one): (1) USGS quadrangle map (or map of equal detail) (2) Aerial photographs Required information: (1) Project location X (2) Drainage area X (3) River reach A.2. EXISTING STRUCTURES (IF APPLICABLE) a. Identify existing structures including upstream and downstream of site (by map). X b. Must describe: (1) Type of structure, span lengths, pier orientation X (2) Cross section beneath structure - stream clearance and skew X (3) Flood history, highwater marks (with dates), nature of flooding, damages (source) X c. Compare stream and existing structure locations with the proposed crossing. X d. Indicate whether existing structures are to remain in place. X A.3. FLOOD INFORMATION a. Elevations of all available highwater marks along the stream w/ dates of occurrence X b. Critical flood elevations of interest (possible damage) X c. Local testimony of flooding (if available) X A.4. ENVIRONMENTAL CONCERNS a. Comments on fish habitats or other environmental concerns. X (1) Warm water or cold water stream? X (2) Trout stocked? X (3) HQ/EV watershed? X b. Continuous or intermittent stream? X A.5. HISTORY OF DRIFT, ICE AND STREAM BANK STABILITY a. Comments on stability of stream banks (i.e. exposed soil, slumping, tilting trees, etc.) X b. Type of material in stream bed (i.e. sand, gravel, large cobbles, etc.) X A.6. PHOTOGRAPHS a. Existing structures X b. Upstream and downstream channel X c. Roadway station ahead and station back X d. Photo location map X A.7. FACTORS AFFECTING WATER STAGES a. High water from other streams. X b. Reservoirs (existing or proposed) and approximate date of construction. X c. Flood control projects (give status, e.g. control structures, operator, and operating policy). X d. Other controls. X A.8. DEBRIS Indicate if debris can be a problem at the structure site. A.9. SITE INSPECTION RECORDS Dates and other information relative to site inspection(s) made by the engineer X X PAGE 11

16 (3) HYDROLOGIC AND HYDRAULIC REPORT CHECKLIST Project: S.R FVR, Chester County Subject: S.R FVR over Beaver Run Date: Reviewer(s): James Kramperth, PE & Jennifer Gutshall, PE District: PennDOT District 6-0 ITEM PRESENT DESCRIPTION YES NO N/A A.10. LINE AND GRADE APPROVAL Indicate date of Line and Grade Approval (Design Field View). (Verbal Approval ) X B. HYDROLOGIC ANALYSIS 1. Show drainage area above proposed crossing (note method of determining area) X 2. Supply flood records (if applicable) X 3. Acceptable hydrology methods X (1) Use of stream gage records (WRC method) (2) Rational Method (up to 200 acres) (3) Regression models/equations PSU-IV (Comparison Only) USGS (4) HEC-1 (may be used within the Watershed Modeling System program) (5) TR-55 (10 acres to 3.1 sq. miles; can also be used within WMS) (6) EFM-2 (1 to 2000 acres) 4. Note FEMA FIS peak discharges and method used (if applicable). X 5. Show flood-frequency curve for the site. X 6. Show stage-discharge-frequency curve for the site (existing and proposed conditions). X C. HYDRAULIC ANALYSIS a. Is the proposed project in a FEMA study area? (circle one) Yes No (1) Original FIS study and flood map(s) provided X (2) Study is referenced in the text X (3) Proposed structure encroaches on (check one): X 100-year floodplain (floodway fringe) 100-year floodway neither (4) Is there an increase in the 100-year water surface elevation? Yes No b. Existing vs. Proposed conditions: (1) velocities X (2) backwater elevations X (3) bridge opening sizes X c. Acceptable hydraulic methods for the site (check the method used) X (1) HEC-RAS (bridge and culvert design, water surface profiles) (2) HY-8 (culvert design) (3) HDS-5 (culvert design - equivalent to HY-8) (4) HEC-2 (water surface profiles) (5) WSPRO (only use when a FEMA map revision is necessary) (6) Visual Urban (HY-22 - mostly urban drainage applications) (7) Other List: d. Model validation X (1) Calibration with known high water marks or storm events X (2) Explanation of model warnings and errors X e. Estimated scour depths - contraction, pier and abutment (refer to Design Manual, Part 4) X f. Riprap sizing for bank, pier and abutment protection [e & f: PENDING CORE BORINGS] X g. Temporary Stream Crossings, Access Roads or Cofferdams X D. RISK ASSESSMENT Narrative description of factors related to the 100-year flood E. SUMMARY DATA SHEET Complete all information listed in Design Manual, Part 2, Section 10.7.E (Figure ). X X PAGE 12

17 (3) HYDROLOGIC AND HYDRAULIC REPORT CHECKLIST Project: S.R FVR, Chester County Subject: S.R FVR over Beaver Run Date: Reviewer(s): James Kramperth, PE & Jennifer Gutshall, PE District: PennDOT District 6-0 DESCRIPTION F. PRELIMINARY COST ESTIMATE Preliminary cost estimates of the proposed structure or channel change ITEM PRESENT YES NO N/A G. DRAWINGS 1. Roadway plans and profiles indicating the following information: a. Layout of existing and proposed structures, stream channels and wetlands. X b. Adjacent topographic features with key elevations or contours shown. X c. Flood limits of the existing and proposed structures and/or channels. X d. Flood easement (if provided) X e. Temporary stream crossing, access road, cofferdam, diversion facility, etc. X f. The magnitude, frequency and pertinent water surface elevation for specified floods. X 2. Profile of stream showing bed slope, normal water surface, and flood water surfaces X 3. Cross-sections perpendicular to flood flow: a. upstream (500 ft) X b. Immediately upstream of proposed and/or existing crossings X c. Immediately downstream of proposed and/or existing crossings X d. downstream (500 ft) X 4. Plan drawing showing the location and orientation of all cross sections used for backwater X analysis (should be to scale and show contouring and all important hydraulic features) 5. Floodway maps and flood profiles where there are detailed FEMA Flood Insurance Studies X 6. Wetland Mitigation Plans X X PAGE 13

18 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6076 FAIRVIEW ROAD OVER BEAVER RUN EAST NANTMEAL TOWNSHIP, CHESTER CO. APPENDIX A Photographic Documentation

19 ...\photo orientation_pdf.dgn 10/2/2007 2:14:07 PM

20 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6093 EAST NANTMEAL TOWNSHIP CHESTER COUNTY PHOTO NO. 1: Upstream Bridge Elevation. PHOTO NO. 2: Upstream Face of East Span of Bridge. WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors Page A-1

21 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6093 EAST NANTMEAL TOWNSHIP CHESTER COUNTY PHOTO NO. 3: Stream Channel, Looking Downstream PHOTO NO. 4: Stream Channel, Looking Upstream Towards Bridge WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors Page A-2

22 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6093 EAST NANTMEAL TOWNSHIP CHESTER COUNTY PHOTO NO. 5: Stream Channel, Looking Upstream From Bridge PHOTO NO. 6: Stream Channel, Looking Upstream WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors Page A-3

23 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6093 EAST NANTMEAL TOWNSHIP CHESTER COUNTY PHOTO NO. 7: Stream Channel 100 ft Upstream of the Bridge, Looking Upstream PHOTO NO. 8: Stream Channel 200-ft Upstream from Bridge, Looking Downstream Towards Scour Hole WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors Page A-4

24 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6093 EAST NANTMEAL TOWNSHIP CHESTER COUNTY PHOTO NO. 9: Downstream West Overbank PHOTO NO. 10: West Approach Roadway, Looking East Note: Low point of alignment is immediately east of the bridge. WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors Page A-5

25 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6093 EAST NANTMEAL TOWNSHIP CHESTER COUNTY PHOTO NO. 11: Low point of roadway alignment east of the bridge. Note: Garage to the left. PHOTO NO. 12: West Approach Roadway, Looking West. Note: Driveway leading to residence located on the right. WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors Page A-6

26 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6093 EAST NANTMEAL TOWNSHIP CHESTER COUNTY PHOTO NO. 13: 1817 Pottstown Pike, Looking South from Fairview Road PHOTO NO. 14: Garage Located in Northeast Quadrant; North of Residence at 1817 Pottstown Pike. P:\2005\ \Design\H&H Report\Photos_4031.doc WHITNEY, BAILEY, COX & MAGNANI, LLC Consulting Engineers, Architects, Planners, & Surveyors Page A-7

27 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6076 FAIRVIEW ROAD OVER BEAVER RUN EAST NANTMEAL TOWNSHIP, CHESTER CO. APPENDIX B Hydrologic Computations

28 PROJECT SITE FLOW VICINITY MAP S.R. 4031, Section FVR SCALE: 1 = 3 Miles Segment 0170, Offset 6093 Fairview Road Over Beaver Run East Nantmeal Township, Chester County B-1

29 FLOW PROJECT SITE USGS QUADRANGLE - POTTSTOWN, PA SCALE: 1-in = 2000-ft LOCATION MAP S.R. 4031, Section FVR Segment 0170, Offset 6093 Fairview Road Over Beaver Run East Nantmeal Township, Chester County B-2

30 B-3

31 B-4

32 B-5

33 B-6

34 B-7

35 B-8

36 B-9

37 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6076 FAIRVIEW ROAD OVER BEAVER RUN EAST NANTMEAL TOWNSHIP, CHESTER CO. APPENDIX C Water-Surface Profiles and Summary Tables

38 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6076 FAIRVIEW ROAD OVER BEAVER RUN EAST NANTMEAL TOWNSHIP, CHESTER CO. APPENDIX C-1 Existing Conditions

39 C-1-1

40 C-1-2

41 C-1-3

42 C-1-4

43 C-1-5

44 C-1-6

45 C-1-7

46 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6076 FAIRVIEW ROAD OVER BEAVER RUN EAST NANTMEAL TOWNSHIP, CHESTER CO. APPENDIX C-2 Proposed Conditions

47 C-2-1

48 C-2-2

49 C-2-3

50 C-2-4

51 C-2-5

52 C-2-6

53 C-2-7

54 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6076 FAIRVIEW ROAD OVER BEAVER RUN EAST NANTMEAL TOWNSHIP, CHESTER CO. APPENDIX D Cross-Section Plots

55 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6076 FAIRVIEW ROAD OVER BEAVER RUN EAST NANTMEAL TOWNSHIP, CHESTER CO. APPENDIX D-1 Existing Conditions

56 D-1-1

57 D-1-2

58 D-1-3

59 D-1-4

60 D-1-5

61 D-1-6

62 D-1-7

63 D-1-8

64 D-1-9

65 D-1-10

66 D-1-11

67 D-1-12

68 D-1-13

69 D-1-14

70 HYDROLOGIC & HYDRAULIC STUDY REPORT S.R. 4031, SECTION FVR SEGMENT 0170, OFFSET 6076 FAIRVIEW ROAD OVER BEAVER RUN EAST NANTMEAL TOWNSHIP, CHESTER CO. APPENDIX D-2 Proposed Conditions (Bridge Sections Only)

71 D-2-1

72 D-2-2

73 D-2-3

74 D-2-4

75 D-2-5

76 D-2-6

77 D-2-7

78 D-2-8

79 D-2-9

80 D-2-10

81 D-2-11

82 D-2-12

83 D-2-13

84 D-2-14

85 D-2-15