What Does MS4 Mean to You?

A presentation on MS4 and sanitary sewer systems, discussing surface water quality regulations, the history of water quality, the new MS4 watershed-based water quality improvement plan, challenges with bacteria TMDLs, and strategies for identifying sewer exfiltration and storm drain infiltration areas. The content also covers a phased approach for investigation and potential sources of bacteria in sewer systems.

• Sewer systems
• Storm drain contamination
• Water quality regulations
• Bacteria TMDLs
• Sewer exfiltration

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1. http://farm5.static.flickr.com/4147/5221122944_cd728b8963.jpghttp://farm5.static.flickr.com/4147/5221122944_cd728b8963.jpg What Does MS4 Mean to You? A study of sewer and storm drain cross contamination Presented by Michael Hill, PE and Steve Jepsen Presented to:

2. MS4 and Sanitary Sewer What will we talk about? A little about surface water quality regulations What a sewer agency is doing about them The goal: A look at future regulations Start thinking of how MS4 might affect us

3. What is MS4? Municipal 1. Separate 2. Storm 3. Sewer 4. System

4. The History of Water Quality 1. The Roman Empire 800 BC 2. The Industrial Revolution 1800s 3. The Clean Water Act 1972 4. CMOM - 2002 5. WDR - 2006 6. MS4 2013 (latest version)

5. The New MS4 Watershed based Water Quality Improvement Plan (WQIP) NGO review Numerical Limits TMDL Total Maximum Daily Limit San Diego County estimate 20 year TMDL cost in billions of $ Bacteria TMDLs Manage new projects to pre-development conditions Extensive monitoring

6. MS4 and Sanitary Sewer Aren t we glad we don t have to deal with this? Think again Bacteria TMDLs are expensive Storm Water programs do not have direct funding What is a potential source of bacteria? How do you prove the sewer is not a source?

7. Sewer Exfiltration/MS4 Infiltration Identify Potential Areas of: Sewer Exfiltration And Storm Drain Infiltration Uncommon Situation Where to Start? (Sercu et al. 2011, ES&T)

8. Phased Approach Each phase narrows search Ph I Desktop Portion (GIS, rec dwgs, CCTV) Ph II Field Investigation (CCTV Storm Drains) Ph III Field Testing (dye, soil, sampling) Ph IV Pipe Rehab Phase I Completed

9. Desktop Investigation Contributing Factors Pipe Crossings Vertical Separation Sewer Pipe Condition Storm Drain Mat l/Size Soil Type

10. Sewer Collection System Watershed study area: 507 sewer pipes 93,000 ft (18 miles) Watershed Study Area

11. Sewer and Storm Drain System Watershed Area: 3,200 acres (5 sq.mi ) Investigate: Closed Pipe And Open Channels Open Channel Storm Drain Closed Channel Storm Drain Sewer Pipe

12. Sewer/Storm Drain Crossings GIS Spatial Queries Worked w/ City GIS staff Join storm drain data to sewer data Join soil data Sewer Crossing Storm Drain

13. GIS Selection Results 107 (21%) sewer pipes selected for further study Depends on GIS accuracy

14. Data Analysis Exported GIS Data to Excel Compiled data into categories Missing Data Use record drawings Spatial Relationship Ground Water Sewer Pipe Storm Drain Pipe Soil Priority FINAL SCORE Site ID HA Vert. Dist. SCORE Horz. Dist SCORE AVERAGE TOTAL SCORE In Valley? SCORE Swr Depth SCORE Vert. Dist. SCORE AVERAGE TOTAL SCORE Length 0 5 9 1 3.0 9.0 y 0 5 9 1 3.0 9.0 n 4 3 0 3 3.0 9.0 n 0 5 8 1 3.0 9.0 y 0.5 5 0 3 4.0 12.0 n 1 5 0 3 4.0 12.0 y 0.5 5 0 3 4.0 12.0 y 0 5 4 2 3.5 10.5 y 2 4 0 3 3.5 10.5 y 2 4 0 3 3.5 10.5 y 0.5 5 0 3 4.0 12.0 y 2 4 12 1 2.5 7.5 y 0 5 0 3 4.0 12.0 n 0.5 5 0 3 4.0 12.0 y Dia. 8 8 8 8 8 12 8 8 12 8 8 8 8 10 Installed Flow Depth SCORE Rec. Dwg. Material Defect Severity SCORE EMA SCORE AVERAGE TOTAL SCORE Storm Drain ID 1986 0.5 0 D1818 PVC none 1988 2.7 1 D3114 PVC none 1987 0.3 0 D3066 PVC none 1986 0.5 1 D1818 PVC none 1997 1.7 1 D3509 PVC none 1983 3.9 2 D1875 PVC/DIP small 1988 1.8 1 D3114 PVC/DIP none 1988 3.3 2 D3114 PVC none 1986 2.5 1 D1934 VCP small 1987 1.6 1 D1973 PVC none 1987 1.5 1 D1973 VCP/PVC small 1979 1.9 1 D1545 VCP none 1987 0.5 0 D1698 PVC medium 1965 5.1 2 VSD001 VCP high SD Type Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Unknown Trapezoidal Trapezoidal Trapezoidal Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert SD Shape Circular Circular Circular Circular Circular Pipe Arch Rectangular Rectangular Circular Circular Circular Circular Circular Circular SD Material SCORE 2 2 2 2 2 2 2 2 3 2 2 2 2 3 Size 24 42 18 24 48 96x72 120x96 120x96 24 24 24 24 21 54 SCORE 3 3 2 3 4 5 5 5 3 3 3 3 2 4 Age SCORE AVERAGE TOTAL SCORE 27 2 2.3 30 2 2.3 26 2 2.0 27 2 2.3 16 2 2.7 30 2 3.0 25 2 3.0 25 2 3.0 27 2 2.7 23 2 2.3 23 2 2.3 23 2 2.3 26 2 2.0 48 3 3.3 Soil Type BlC2 DaC LeD2 BlC2 DaC SbC SbC, LpD2 SbC, LpD2 SbC, DaD, LpD2 DaC DaC DaC DaE2 WmC, LpD2 Perm. (in/hr) SCORE AVERAGE TOTAL SCORE 3.18 3 0.13 1 3.25 3 3.18 3 0.13 1 0.415 1 0.415 1 0.415 1 0.32 1 0.13 1 0.13 1 0.13 1 0.13 1 2.2825 3 93 100 103 116 169 176 223 225 257 276 277 278 302 333 SL SL LA SL SL SL SL SL SL SL SL SL LA SL 3 1 1 3 1 3 3 3 3 3 3 3 1 3 12 11 5 12 8 7 2 6 3 4 4 4 4 10 3 3 1 3 2 2 1 2 1 1 1 1 1 2 0 0 4 0 1 1 1 0 2 2 1 2 0 1 5 5 5 5 5 5 5 5 5 5 5 5 5 5 3.7 3.0 2.3 3.7 2.7 3.3 3.0 3.3 3.0 3.0 3.0 3.0 2.3 3.3 7.3 6.0 4.7 7.3 5.3 6.7 6.0 6.7 6.0 6.0 6.0 6.0 4.7 6.7 82 0 No No No No No No No No No No No Yes No No 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0.0 0.5 0.0 0.5 0.5 1.0 0.5 1.0 0.5 0.5 0.5 1.0 0.0 1.0 0.0 2.5 0.0 2.5 2.5 5.0 2.5 5.0 2.5 2.5 2.5 5.0 0.0 5.0 CC-02416 CC-02361 CC-00314 CC-02416 CC-02350 CC-02087 CC-02418 CC-02418 OC-00576 CC-02377 CC-02377 CC-02377 CC-00319 CC-02381 Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Structural Plate Reinforced concrete pipe Reinforced concrete pipe Corrugated metal pipe Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Corrugated metal pipe 2.3 2.3 2.0 2.3 2.7 3.0 3.0 3.0 2.7 2.3 2.3 2.3 2.0 3.3 3.0 1.0 3.0 3.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 3.0 6.0 2.0 6.0 6.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 6.0 24.7 21.8 21.7 27.2 24.5 28.7 25.5 27.2 23.7 23.3 24.8 22.8 20.7 33.0 261.55 257.5 146 170 300 278 118 261 110 203 82.01 243 267 361 362 368 382 590 SL SL SL SL LA 1 1 0 2 3 5 5 5 4 4 0 0 3 3 1 3 3 4.0 4.0 3.0 3.5 3.5 12.0 12.0 9.0 10.5 10.5 y y y y n 3 3 3 3 1 6 5 2 1 2 2 1 1 1 0 2 3 5 5 5 5 5 3.3 3.0 3.3 3.3 2.3 6.7 6.0 6.7 6.7 4.7 80 141 225 177 134 8 8 8 8 8 1987 1987 1967 1987 1982 0.6 1.1 0.7 0.8 0.6 1 1 1 1 1 D1973 D1973 D1046 D1973 D1487-S PVC PVC VCP PVC VCP none none high none medium No No No No Yes 0 0 0 0 1 0.5 0.5 0.5 0.5 1.0 2.5 2.5 2.5 2.5 5.0 CC-02374 CC-02367 CC-02306 CC-02374 CC-00368 Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Circular Circular Circular Circular Circular Reinforced concrete pipe Reinforced concrete pipe Orangeber Perforated Reinforced concrete pipe Corrugated metal pipe 2 2 4 2 3 18 30 6 18 18 2 3 1 2 2 23 23 46 23 35 2 2 3 2 2 2.0 2.3 2.7 2.0 2.3 2.0 2.3 2.7 2.0 2.3 DaC DaC 0.13 0.13 0.13 0.13 3.25 1 1 1 1 3 1.0 1.0 1.0 1.0 3.0 2.0 2.0 2.0 2.0 6.0 25.2 24.8 22.8 23.7 28.5 15 1 0 10 6 3 DaC, AwC DaC LeC2, LeE3 6 SL SL SL SL SL SL SL LA LA SL SL SL SL SL LA SL SL SL SL SL SL -12 -4 -14 -7 -10 -10 -16 -1 -3 -4 -4 -6 -9 -10 -3 -2 -1 -3 -9 -1 -2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 9 3 1 1 3 1 1 3 3 1 1 3 3 2 1 1 3 1 3 1 1 1 1.5 0.5 0.5 1.5 0.5 0.5 1.5 1.5 0.5 0.5 1.5 1.5 1.0 0.5 0.5 1.5 0.5 1.5 0.5 0.5 0.5 4.5 1.5 1.5 4.5 1.5 1.5 4.5 4.5 1.5 1.5 4.5 4.5 3.0 1.5 1.5 4.5 1.5 4.5 1.5 1.5 1.5 y y y y y y y n n n y n n n n y y n n n n 3 3 3 3 3 3 3 1 1 1 3 1 1 1 1 3 3 1 1 1 1 12 8 14 18 10 10 16 6 3 4 11 6 9 10 3 8 14 9 9 11 10 3 2 3 4 2 2 4 2 1 1 3 2 2 2 1 2 3 2 2 3 2 -12 -4 -14 -7 -10 -10 -16 -1 -3 -4 -4 -6 -9 -10 -3 -2 -1 -3 -9 -1 -2 1 3 1 1 1 1 1 5 3 3 3 2 1 1 3 4 5 3 1 5 4 2.3 2.7 2.3 2.7 2.0 2.0 2.7 2.7 1.7 1.7 3.0 1.7 1.3 1.3 1.7 3.0 3.7 2.0 1.3 3.0 2.3 4.7 5.3 4.7 5.3 4.0 4.0 5.3 5.3 3.3 3.3 6.0 3.3 2.7 2.7 3.3 6.0 7.3 4.0 2.7 6.0 4.7 300 319 288 350 325.64 243.15 350 135 94.86 67 147 214 10.16 115 126.5 295 172 206 204 101 283 8 8 8 1991 1978 1989 1983 1983 1983 1983 1985 1982 1990 1986 1988 2006 1985 1982 1986 1986 1986 1985 1988 1988 4.1 0.8 4.1 4.2 5.3 5.8 4.2 0.8 0.5 0.6 0.9 0.4 4.1 0.4 0.9 0.6 0.6 0.9 0.4 1.7 1.0 2 1 2 2 2 2 2 1 0 1 1 0 2 0 1 1 1 1 0 1 1 D3122 D1452-S D3210 D1875 D1875-S D1875-S D1875-S D1777 D1487 D3299-S D1818 D3114 D3761 D1818-S D1487-S D1818 D1818 D1818 D1818-S D3114 D3114 VCP VCP PVC PVC PVC PVC PVC PVC VCP PVC VCP PVC PVC VCP VCP PVC PVC PVC VCP PVC PVC No No No No No No No No No No No No No No No No No No No No No 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1.0 0.5 1.0 1.0 1.0 1.0 1.0 0.5 0.0 0.5 0.5 0.0 1.0 0.0 0.5 0.5 0.5 0.5 0.0 0.5 0.5 5.0 2.5 5.0 5.0 5.0 5.0 5.0 2.5 0.0 2.5 2.5 0.0 5.0 0.0 2.5 2.5 2.5 2.5 0.0 2.5 2.5 CC-02593 CC-02366 OC-00859 CC-02086 OC-00515 OC-00515 OC-00515 CC-00375 OC-00077 OC-00577 CC-02173 OC-00575 OC-00883 OC-00514 OC-00077 CC-02340 CC-02416 CC-02419 OC-00514 CC-02361 CC-02361 Pipe Culvert Horizontal Elipse Pipe Culvert Trapezoidal Pipe Culvert Trapezoidal Trapezoidal Trapezoidal Pipe Culvert Trapezoidal Trapezoidal Pipe Culvert Triangular Unknown Trapezoidal Trapezoidal Pipe Culvert Pipe Culvert Pipe Culvert Trapezoidal Pipe Culvert Pipe Culvert Reinforced concrete pipe Reinforced concrete pipe Natural Watercourse Reinforced concrete pipe Natural Watercourse Natural Watercourse Natural Watercourse Asbestos cement pipe Portland Cement Concrete Portland Cement Concrete Reinforced concrete pipe Portland Cement Concrete Asphalt Cement Natural Watercourse Portland Cement Concrete Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Natural Watercourse Reinforced concrete pipe Reinforced concrete pipe 2 2 4 2 4 4 4 2 2 2 2 2 3 4 2 2 2 2 4 2 2 0 1 3 3 4 3 3 3 2 2 3 3 2 1 3 2 2 3 2 3 3 3 22 35 100 40 100 100 100 28 35 35 27 30 7 100 35 27 27 27 100 30 30 2 2 3 2 3 3 3 2 2 2 2 2 1 3 2 2 2 2 3 2 2 1.7 2.3 3.3 2.7 3.3 3.3 3.3 2.0 2.0 2.3 2.3 2.0 1.7 3.3 2.0 2.0 2.3 2.0 3.3 2.3 2.3 1.7 2.3 3.3 2.7 3.3 3.3 3.3 2.0 2.0 2.3 2.3 2.0 1.7 3.3 2.0 2.0 2.3 2.0 3.3 2.3 2.3 LpC2 DaC 0.415 0.13 2.2825 1.7975 0.415 0.2725 0.415 3.25 3.25 0.13 0.415 0.415 0.415 3.465 3.25 1.655 3.18 1.655 3.465 0.13 0.2725 1 1 3 2 1 1 1 3 3 1 1 1 1 3 3 2 3 2 3 1 1 1.0 1.0 3.0 2.0 1.0 1.0 1.0 3.0 3.0 1.0 1.0 1.0 1.0 3.0 3.0 2.0 3.0 2.0 3.0 1.0 1.0 2.0 2.0 6.0 4.0 2.0 2.0 2.0 6.0 6.0 2.0 2.0 2.0 2.0 6.0 6.0 4.0 6.0 4.0 6.0 2.0 2.0 17.8 13.7 20.5 21.5 15.8 15.8 20.2 20.3 12.8 11.7 17.3 11.8 14.3 13.5 15.3 19.0 19.7 17.0 13.5 14.3 13.0 10 25 39 52 53 59 73 75 76 94 97 102 105 109 113 115 122 130 133 134 Circular Trapezoidal Circular Trapezoidal Trapezoidal Trapezoidal Circular Trapezoidal Trapezoidal Circular Triangular Unknown Trapezoidal Trapezoidal Circular Circular Circular Trapezoidal Circular Circular 24 24 48 24 24 24 18 12 36 24 12 8 24 12 18 24 18 24 42 42 10 0 15 15 0 0 12 11 0 0 5 11 12 0 8 0 17 17 17 WmC, LpD2 SbC, BlC2 SbC SbC, DaE2 SbC LeC2, LeE3 LeE3 DaD SbC LpD2 LpD2 FeE2 LeC2, LeE3 BlC2, DaC BlC2 BlC2, DaC FeE2 DaC DaC, LpD2 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 none none none high 136 147 153 154 166 177 178 180 188 191 192 196 198 199 213 238 241 242 250 269 273 297 303 314 315 SL SL SL SL SL SL SL SL SL SL SL SL SL LA SL SL SL SL SL SL SL LA LA SL SL -1 -2 -2 -2 -4 -2 -2 -2 -2 -1 -1 -7 -14 -2 -2.0 -2 -2 -2 -6 -2 -6 -6 -2 -9 -9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 3 1 1 1 3 1 1 3 3 3 1 1 3 1 1 3 3 1 3 1 3 1 2 3 1.5 1.5 0.5 0.5 0.5 1.5 0.5 0.5 1.5 1.5 1.5 0.5 0.5 1.5 0.5 0.5 1.5 1.5 0.5 1.5 0.5 1.5 0.5 1.0 1.5 4.5 4.5 1.5 1.5 1.5 4.5 1.5 1.5 4.5 4.5 4.5 1.5 1.5 4.5 1.5 1.5 4.5 4.5 1.5 4.5 1.5 4.5 1.5 3.0 4.5 n n y y n y y y y y y y n n n y y y n y n n n n n 1 1 3 3 1 3 3 3 3 3 3 3 1 1 1 3 3 3 1 3 1 1 1 1 1 9 2 3 2 2 1 2 2 2 3 3 3 2 4 1 2 2 2 2 2 3 4 3 2 3 4 -1 -2 -2 -2 -4 -2 -2 -2 -2 -1 -1 -7 -14 -2 -2 -2 -2 -2 -6 -2 -6 -6 -2 -9 -9 5 4 4 4 3 4 4 4 4 5 5 1 1 4 4 4 4 4 2 4 2 2 4 1 1 2.7 2.7 3.0 3.0 1.7 3.0 3.0 3.0 3.3 3.7 3.7 2.0 2.0 2.0 2.3 3.0 3.0 3.0 1.7 3.3 2.3 2.0 2.3 1.7 2.0 5.3 5.3 6.0 6.0 3.3 6.0 6.0 6.0 6.7 7.3 7.3 4.0 4.0 4.0 4.7 6.0 6.0 6.0 3.3 6.7 4.7 4.0 4.7 3.3 4.0 172 25.75 94.02 312 135.2 140 64.33 215 173 72 125 263 188 48.01 240 123 137 248 300 320.08 156.62 188 126 90 26.88 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 1989 1988 1978 1978 1976 1986 1986 1986 1986 1986 1986 1988 1967 <Null> 1985 1986 1986 1988 1988 1986 1978 1987 1987 1979 1979 1.4 1.9 0.4 0.7 1.2 1.4 1.5 1.0 1.2 1.8 1.4 0.8 1.8 0.9 0.4 1.2 1.2 1.1 0.5 1.8 1.2 1.1 0.7 2.4 2.2 1 1 0 1 1 1 1 1 1 1 1 1 1 1 0 1 1 1 0 1 1 1 1 1 1 D3214 D3114 D1428-S D1428-S D1504-S D1818 D1818 D1818 D1818 D1818 D1818 D3114 NS793 <Null> D1818-S D1818 D1818 D3114 D3114 D1934 D1502 D1698 D1698 D1545 D1545 PVC PVC VCP VCP VCP PVC PVC PVC PVC PVC PVC PVC VCP <Null> VCP PVC PVC PVC PVC PVC VCP VCP VCP VCP VCP none No No No No No No No No No No No No Yes No No No No No No No No No No Yes No 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0.5 0.5 0.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 1.0 0.5 0.0 0.5 0.5 0.5 0.0 0.5 0.5 0.5 0.5 1.0 0.5 2.5 2.5 0.0 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 5.0 2.5 0.0 2.5 2.5 2.5 0.0 2.5 2.5 2.5 2.5 5.0 2.5 CC-02348 CC-02361 CC-02303 CC-02366 OC-00577 CC-02411 CC-02413 CC-02413 CC-02409 CC-02414 CC-02415 OC-00575 CC-02330 CC-03735 CC-02081 CC-02410 CC-02410 CC-02360 OC-00575 OC-00576 CC-02330 CC-00318 CC-00319 CC-02329 CC-02329 Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Trapezoidal Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Triangular Pipe Culvert Pipe Culvert Trapezoidal Pipe Culvert Pipe Culvert Triangular Triangular Trapezoidal Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Pipe Culvert Circular Circular Circular Circular Trapezoidal Circular Circular Circular Circular Circular Circular Triangular Circular Circular Circular Circular Circular Circular Triangular Trapezoidal Circular Circular Circular Circular Circular Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Portland Cement Concrete Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Portland Cement Concrete Orangeber Perforated Reinforced concrete pipe Corrugated metal pipe Reinforced concrete pipe Reinforced concrete pipe Reinforced concrete pipe Portland Cement Concrete Natural Watercourse Orangeber Perforated Reinforced concrete pipe Reinforced concrete pipe Orangeber Perforated Orangeber Perforated 2 2 2 2 2 2 2 2 2 2 2 2 4 2 3 2 2 2 2 4 4 2 2 4 4 18 42 24 24 36 24 24 24 18 24 24 12 6 18 30 18 18 18 12 24 6 21 21 6 6 2 3 3 3 3 3 3 3 2 3 3 2 1 2 3 2 2 2 2 3 1 2 2 1 1 24 30 35 35 35 27 27 27 27 27 27 30 39 30 20 27 27 30 30 100 39 26 26 39 39 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 3 2 2 2 2 2 2.0 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.0 2.3 2.3 2.0 2.3 2.0 2.7 2.0 2.0 2.0 2.0 3.3 2.3 2.0 2.0 2.3 2.3 2.0 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.0 2.3 2.3 2.0 2.3 2.0 2.7 2.0 2.0 2.0 2.0 3.3 2.3 2.0 2.0 2.3 2.3 DaC, LpD2 DaC DaC DaC DaD, AwC BlC2 BlC2 BlC2 SbC BlC2 BlC2 SbC, LpD2 DaC LeD2 FeE2 BlC2 BlC2 SbC LpD2 DaD DaC DaE2 DaE2 DaC DaC 0.2725 0.13 0.13 0.13 0.13 3.18 3.18 3.18 0.415 3.18 3.18 0.415 0.13 3.25 3.465 3.18 3.18 0.415 0.415 0.13 0.13 0.13 0.13 0.13 0.13 1 1 1 1 1 3 3 3 1 3 3 1 1 3 3 3 3 1 1 1 1 1 1 1 1 1.0 1.0 1.0 1.0 1.0 3.0 3.0 3.0 1.0 3.0 3.0 1.0 1.0 3.0 3.0 3.0 3.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2.0 2.0 2.0 2.0 2.0 6.0 6.0 6.0 2.0 6.0 6.0 2.0 2.0 6.0 6.0 6.0 6.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 16.3 16.7 11.8 14.3 11.7 21.3 18.3 18.3 17.7 22.7 22.7 12.0 14.8 19.0 14.8 18.0 21.0 17.0 8.8 19.0 13.0 15.0 12.7 15.7 15.3 10 8 8 4 8 8 8 11 13 13 7 16 4 9 9 9 7 6 10 16 14 7 14 18 14 9 11 0 7 7 0 0 0 14 18 1 19 14 0 0 11 0 17 0 8 5 0 none none none none none none none none 12 8 8 8 8 8 small

15. Scoring Matrix 5 Categories, 12 sub categories Weighted scoring Spatial Relationship Priority Rating Storm Drain Pipe Priority Rating Value 0 1 2 3 4 5 Score Sewer vert dist above SD < 0 ft > 15 ft 6 to 15 ft 4 to 6 ft 2 to 4 ft 0 to 2 ft Horz dist - 5 to 20 ft 2 to 5 ft 0 to 2 ft Average Weight Score Value 1 2 3 4 5 Score SD size <12" 15" to 24" 30" to 48" 54" to 96" > 96" Mat'l HDPE PVC, RCP, etc 15 to 40 yrs CMP Perf, Natr'l Age < 15 yrs Average Weight Score > 40 yrs 2 5 Soil Priority Rating 2 3.0 1.0 3.0 5 1 3.0 3.0 9.0 Ground Water Rating Value 1 2 3 4 5 Score Soil Permeability (in/hr) <.63 .63 to 2 Average Weight Score Value 1 2 3 4 5 Score Pipe in Valley? Sewer Depth Swr above SD no < 5 ft - 5 to 10 ft yes 10 to 15 ft 15 ro 20 ft > 20 ft 3 Average Weight Score < -6 ft -4 to -6 ft -2 to -4 ft -1 to -2 ft > -1 ft 2 to 6.3 6.3 to 20 > 20 1 1.0 2.0 2.0 3 2 2.7 2.0 5.3 Sewer Pipe Priority Rating Total 19.0 Value 0 1 2 3 4 5 Score Defect Severity Flow Depth none minor defect small medium high serious EMA listed no yes Average Weight Score < 1/2" 1/2" to 3" 3" to 12" > 12" 2 0 1 1.0 5.0 5.0

16. Example Site Sewer-Storm Drain Crossing No storm drain invert elevation in GIS Need IE for scoring

17. Example Site (Contd) Review record drawings 1 ft

18. Sewer Pipe Deficiency Assessment Recent CCTV available for all mains Defects relative to exfiltration

19. Phase I Priority Ratings Based on scoring matrix Narrow search down 19 of 507 (4%) sewer pipes above storm drain 12 of 19 (2%) also cross storm drain 6 of 12 (1%) also have defect 2 of 6 (0.3%) also in sandy soil Unaccounted variables/factors highest rating Spatial Relationship Ground Water Sewer Pipe Priority Rating Storm Drain Pipe Priority Rating Soil Priority Rating FINAL SCORE Site ID Rank Vert. Dist. Horz. Dist Avg Total In Valley? Swr Depth Vert. Dist. Avg Total Flow Depth Defect Severity 5 1 3.0 9.0 3 3 5 3 4.0 12.0 3 2 5 3 4.0 12.0 3 1 5 2 3.5 10.5 3 2 4 3 3.5 10.5 3 1 5 3 4.0 12.0 3 1 5 3 4.0 12.0 1 1 5 3 4.0 12.0 3 2 EMA Avg Total SD Mat'l 0 0.3 1.7 0 1.3 6.7 0 0.3 1.7 0 0.7 3.3 0 1.0 5.0 0 1.0 5.0 0 1.0 5.0 0 2.0 10.0 Size 3 5 5 5 3 3 2 4 Age Avg Total Perm. (in/hr) Avg Total 2 2.3 2.3 2 3.0 3.0 2 3.0 3.0 2 3.0 3.0 2 2.7 2.7 2 2.3 2.3 2 2.0 2.0 3 3.3 3.3 116 176 223 225 257 277 302 333 5 5 5 5 5 5 5 5 3.7 3.3 3.0 3.3 3.0 3.0 2.3 3.3 3.7 3.3 3.0 3.3 3.0 3.0 2.3 3.3 1 2 1 2 1 1 0 2 0 2 0 0 2 2 3 4 2 2 2 2 3 2 2 3 3 1 1 1 1 1 1 3 3.0 1.0 1.0 1.0 1.0 1.0 1.0 3.0 6.0 2.0 2.0 2.0 2.0 2.0 2.0 6.0 22.7 27.0 21.7 22.2 23.2 24.3 23.3 34.7 8 3 10 9 7 5 6 1 368 590 5 4 1 3 3.0 3.5 10.5 9.0 3 1 2 1 5 5 3.3 2.3 3.3 2.3 1 1 4 3 0 1 1.7 1.7 8.3 8.3 4 3 1 2 3 2 2.7 2.3 2.7 2.3 1 3 1.0 3.0 2.0 6.0 25.3 29.5 4 2

20. Phase II and III Further Narrow Search Potential sites Further field work to verify or deny Rehab pipe is last step CCTV inspection of Storm Drain Storm drain in good condition and no signs of infiltration Storm drain in poor condition or signs of infiltration Dye Testing No Further Action Water Sampling No Flow or poor conditions for accurate sample Bacteroides detected at only DS sampling point Bacteroides detected at both US and DS sampling points Dye not detected in storm drain Dye detected in storm drain Bacteroides not detected Soil Samples Bacteroides detected Bacteroides not detected No Further Action Repair/Rehab Sewer Pipe

21. Questions? Michael Hill, P.E. Dudek mhill@dudek.com 760.479.4124