Christopher Dwinal, PE Kattie Hartwell, PE Removal of Private Inflow: No Thanks! Not in my Basement or Backyard!

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1 Christopher Dwinal, PE Kattie Hartwell, PE Removal of Private Inflow: No Thanks! Not in my Basement or Backyard! Presented at the 2018 NEWEA Annual Conference

2 Presentation Overview Introduction to Private Inflow Case Studies Cape Elizabeth, ME Berlin, NH Baileyville, ME Funding Mechanisms Pitfalls and Lessons Learned Location - Project Slide 2

3 What is it? Introduction to Private Inflow Location - Project Slide 3

4 Introduction to Private Inflow Why target it? Mainline replacement does nothing to remove infiltration and inflow from private sources Cases exist where mainline replacement actually increased I-I That said, private inflow removal is not for every community Slide 4

5 Introduction to Private Inflow How do you find it? Flow monitoring Smoke testing CCTV inspection Home inspections Location - Project Slide 5

6 What s the big deal? Introduction to Private Inflow Access/Easements Funding Enforcement Other Slide 6

7 Cape Elizabeth, ME Case Study 1 Coastal bedroom community Northern portion of Town flows to South Portland WWTF Maine DEP required CSO Master Plan for bypass elimination 3-party permit for pump station CSO CSO Master Plan developed Removal of I/I determined to be best way to reduce overflows Downstream capacity limitations Slide 7

8 Cape Elizabeth, ME Case Study 1 Investigations Flow monitoring Smoke testing Sewer and manhole inspections Home inspections Location - Project Slide 8

9 Home Inspection Statistics Total Attempted: 188 Total Inspected: 146 Illicit Connections: 40 Types of Illicit Connections 20 Sump Pumps 22 Floor Drains 3 Yard Drains 5 Roof Leaders

10 Cape Elizabeth, ME Case Study 1 Location - Project Slide 10

11 Cape Elizabeth, ME Case Study 1 Funding Considered a number of options Decided on local funding to be paid off using sewer user rates Slide 11

12 Cape Elizabeth, ME Case Study 1 Phase $224,000 Phase $340,000 Phase $423,000 estimated Total cost $987,000 or ~$22,000 per illicit connection removed Slide 12

13 Berlin, NH The City that trees built WWTF flows Average: 2 MGD Peak: 11.5 MGD NH DES required I-I removal to make way for new sewer flows Started during construction of new federal prison Result - City ordinance for users >50,000 gpd to fund I-I removal projects Case Study 2 Slide 13

14 Berlin, NH Investigations 2007 Flow monitoring Smoke testing 2010 & 2012 Sewer and manhole inspections Home inspections 2010 and 2012 set stage for three separate projects Case Study 2 Slide 14

15 Berlin, NH Case Study 2 of home inspections 164 inspections attempted 104 completed (63% success) 52 illicit connections found Sump pumps Floor drains Foundation drains Roof drains What about remaining 60? Slide 15

16 Berlin, NH Case Study 2 Slide 16

17 Berlin, NH Funding City utilized $2 million balance of $6 million RD loan/grant Work on private property not eligible Work funded by rate payers, not individual residents Case Study 2 Slide 17

18 Berlin, NH Phase $427,000 (pipe relining only) Phase $915,000 Phase $836,000 Total cost $1,751,000 or ~$38,000 per illicit connection removed Case Study 2 Slide 18

19 Baileyville, ME Rural Downeast mill town WWTF flows Average: 0.3 MGD Peak: 3+ MGD Permit violations during wet weather events Consent agreement issued in 2003 Removal of I/I required by MEDEP before expansion at WWTF Case Study 3 Slide 19

20 Baileyville, ME Investigations (Before 2006) Flow monitoring Smoke testing Sewer and manhole inspections Home inspections Case Study 3 Slide 20

21 Baileyville, ME Case Study Properties Inspected 90 Properties with Private Inflow Slide 21

22 Baileyville, ME Case Study 3 Slide 22

23 Baileyville, ME Funding Case Study 3 Local loan for work on private property SRF loan for work within public ROW Both loans paid using sewer user rates Slide 23

24 Baileyville, ME Case Study 3 Phase $297,000 Phase $757,000 Total cost $1,054,000 or ~$9,000 per illicit connection removed Slide 24

25 Funding Mechanisms Municipality vs. property owner Funding agencies Rural Development State Revolving Loan Project specific funding Local fund Forgive sewer rates Slide 25

26 Pitfalls and Lessons Learned Electrical and plumbing services Backup power for sump pumps Reliability of the system Landscaping restoration Enforcement Slide 26

27 Contact Information Chris Dwinal, PE ME Wastewater Group Leader (207) Kattie Hartwell, PE Lead Project Engineer (207) Slide 27

28 Christopher Dwinal, PE Kattie Hartwell, PE Thank You Removal of Private Inflow: No Thanks! Not in my Basement or Backyard!