Key I/I Reduction Plan Components -...

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The McMAHON Way. Values, Culture, Relationships… for over 100 Years. 1445 McMAHON DRIVE NEENAH, WI 54956 920 751 4200 [email protected] www.mcmgrp.com ID: PPT\2015\WRWA Technical Confer – I-I Reduction pres.pptx BDW:jmk 8/31/2015

WRWA 27th ANNUAL TECHNICAL CONFERENCE

MARCH 24, 2015

Brad D. Werner, P.E.


Key I/I Reduction Plan Components

Understanding of the Collection System

Developing solid Ordinances and Policies

Long-Range Plan Development

Capital Project Implementation

Post-Construction Investigation/Record Keeping/Tracking

Financing

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CMOM

Definition • Capacity, Management, Operations and Maintenance

Uses • Better manage, operate and maintain collection systems • Investigate capacity constrained areas of the collection

system • Respond to sanitary sewer overflow (SSO events)


Wisconsin Department of Natural Resources (WDNR)

Administrative Code Chapter NR110

NR110.03 Definitions

Infiltration "Infiltration" means water other than wastewater that enters a sewerage system (including sewer service connections) from the ground through such sources as defective pipes, pipe joints, connections, or manholes. Infiltration does not include, and is distinguished from, inflow.

Inflow Inflow "Inflow" means water other than wastewater that enters a sewerage system (including sewer service connections) from sources such as roof leaders, cellar drains, yard drains, area drains, foundation drains, drains from springs and swampy areas, manhole covers, cross connections between storm sewers and sanitary sewers, catch basins, cooling towers, storm waters, surface runoff, street wash waters, or drainage. Inflow does not include, and is distinguished from, infiltration.

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I & I Reduction

Public Sewer vs Laterals

Rehab Studies generally indicate • Mainline Only: 20-25% I/I Reduction • Mainline and laterals to R/W: 25-50% Reduction • Mainline and laterals to home: 50-80% Reduction

The “Gold” Standard • Precast Manholes with chimney seals • PVC Mainline • PVC Laterals • Sump Pumps / Drain Tile • Mini-Storm Laterals


The Collection System Basin Approach

“Time to Break it Down”

Basin Map Advantage • Breakdown Collection System into reasonable

sections for evaluation

• Monitoring and investigation of each basin’s flow

• Rank basins based on I/I contribution

• Evaluate all sources of I/I

• Track post construction monitoring and evaluation

• Refinement of the I/I program, based on results

• Effective and organized long-range planning

• Enhanced and more detailed understanding of the collection system

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Monitoring / Investigation Techniques “Getting to know and understand

your Collection System”

Interviews

Flow Metering

Smoke Testing

Manholes Inspections

Bottle Racks A Bottle Rack can be installed in a manhole to determine if a manhole experiences surcharging

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Monitoring / Investigation Techniques “Getting to know and understand

your Collection System”

CCTV Televising • Mainline • Laterals

Lift Stations • Monitoring the Pump Run Times on

Lift Stations to Track Flows


Monitoring / Investigation Techniques continued

Dye Flood Testing

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Document Visually

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Sources of Inflow/Infiltration

Public System • Mainline

Joints

Fractured Pipe

Root Penetration

Lateral Connections


Sources of Inflow/Infiltration continued

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Public System • Manholes

Castings

Adjusting Rings

Block/Brick Failures

Leaking Barrel Joints

Pipe Connections

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CASTING ROAD

BLOCKS IN CONE SECTION SHIFTED

ADJUSTING RING

BENCH

MH A5-743


HOLE IN STREET NEXT TO CASTING

MORTAR UNDER CASTING DETERIORATING

CASTING AT ROAD

BENCH

MH A5-707

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Public System • Clearwater Sources in the Right-of-way

High groundwater table

Sanitary sewer trench acts as French drain

Usually lowest utility

Water follows the trench

Leaking water mains and services

Exfiltration from storm sewer



Private System - Laterals • Joints • Fractured Pipe • Root Intrusion • Broken Riser • Rolled Gasket • Pulled Joint

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Private System • Clearwater Sources on the Private Side

Groundwater table

Lateral trench acts as French drain

Leaking water service

No drain tile

Direct or indirect connection to drain tile,

No sump pump

Sump pump connection to sanitary

Poor surface drainage away from home

Clearwater entering basement, then to the floor drain



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Back to the Basin Map

Organize Data Visually

GIS Advantages • Layering your data

Fine Tune Your Game Plan

Predict the Potential for Success

Develop Capital Improvement Plan

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Back to the Basin Map

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Ordinance and Policy Development

Review of Existing Ordinance and Policies • Definitions

Lateral ownership/maintenance/ replacement responsibility

Home to Mainline

Home to R/W or Easement

Acceptable pipe materials

Mainline

PVC, Clay, Concrete, ABS Truss, Ductile Iron

Laterals

PVC, Clay, Concrete, ABS Truss, Transite, Cast Iron



Review of Existing Ordinance and Policies • Definitions

Defective determination

Pipe material

Evidence of leaking

Roots

Mineral deposits

Slope

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Replacement Ordinance / Policy

• Laterals Replacement order

Cost Share

Lateral in R/W

Lateral on Private Property

Limits of Lateral Reconstruction

Assessment Policy

Private Project

Utility Assistance



Non-Sanitary Sewer-Related I/I Reduction Projects

• Sump Pumps / Drain Tile Inventory homes for working sump pump / drain tile

Identify / eliminate cross-connections

Require sump pump installations

Require drain tile installation

Annual inspection program

• Mini-Storm Sewer Program Provide mini-storm for sump pump discharge

Assessment policy

Long-range plan

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Remediation Techniques for Private Services

Conventional Reconstruction

ADVANTAGES

DISADVANTAGES

Proper slope

Remove dips and straighten alignment

Change pipe size

Pipe joints and lateral connection at main

Uncovers unknown problems

Maximizes useful life

Expensive restoration cost to homeowner

Physical constraints (garage, sheds, patios, decks, etc.)

Higher overall cost with restoration

Rear yard sewers / easements

Sewers in alleys



Sliplining

Less restoration costs

Pipe can be Schedule 40 PVC

Pipe joints and lateral connection at main

Rehabilitate under physical constraints

Pipe size must be reduced

Dips and sags remain

Can not traverse bends or sudden alignment changes

ADVANTAGES

DISADVANTAGES

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Pipe Bursting


Pipe joints

Size option

Ability to traverse bends and other alignment changes



ADVANTAGES

DISADVANTAGES



Cured-In-Place Liner


No joints

Ability to traverse bends and other alignment changes


Connections to main


Reduced effective pipe size

Cost is generally substantially higher than sliplining or bursting

ADVANTAGES

DISADVANTAGES

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Private Laterals – Public Projects

Private Lateral Work Bid Under Municipal Contract

Homeowners Notified of Non-compliant Laterals

Homeowner Given 2 Options • Hire their own contractor

• Complete under Municipal Contract Waiver of Special Assessment and Right to Enter Property

• 98% Participation Under Municipal Contract



Homeowner Advantages

• Municipal Contract Price

• Project Management by the Municipality

• Qualified Contractor

• Municipal Contract Warranty

• Municipal Financing Options

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Municipal Advantages

• Project Control

• Single Contractor vs Multiple

• More Efficient to Manage and Oversee

• Most Cost-Effective

• Project Documentation Records

• Improves Public Education on I&I



Post Construction Problems

• Contractor Defects <5%

• Sump Pump Runs More

• Basement Floors and Walls Weeping

• Water Running on the Basement Floor During Rain Events

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Private Laterals – Public Projects Typical Costs

Estimated Costs for a Typical 4-inch Lateral in Conjunction with a Municipal Relay Project

Lateral portion on Private Property Excavated to an Outside Home Reconnection

35’ at $53/L.F. $ 1,855.00

Lateral Outside Reconnection $ 500.00

Estimated Cost $ 2,355.00

Lateral portion on Private Property Pipe Burst to Home Reconnection

35’ at $11/L.F. $ 385.00

Lateral Reconnection in Home $ 900.00

Fernco Connection $ 20.00

4” Bend $ 25.00

4” Cleanout $ 35.00

Concrete Floor Patch $ 60.00

Estimated Cost $ 1,425.00

No restoration of turf, landscaping, pavement, structures, etc. is included. Contractor shall compact and level the trench with trench spoils of restoration by the property owner.


Associated Remediation Projects

Storm Sewer Replacement

Sump Pump Installation

Mini-Storm Sewer Installation

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Post-Construction Items

Flow Monitoring • Establish Before / After Flows

Investigation of any Unresolved I/I Sources identified during Construction

Modification of Long-Range Plan

Record Documentation • Record Drawings • Document I/I Sources Removed • Update GIS


What We’ve Learned…

Successful I/I Programs require doing the Complete Job

• Mainline Replacement • Lateral Replacement to the Home • Address Sump Pumps • Storm Sewer / Mini-storm

In order to identify problems, you need to be actively looking for problems

There are very few “Big Ones”

“Band-Aids” are not the answer

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What We’ve Learned…

Education • Governing Bodies • Customers

Offer Solutions

Post-Project Evaluations

Develop a Long-term Cost-effective Program • Annual Projects • 5 – 10 year Plan

Q A

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