INVESTIGATING INFILTRATION & INFLOW

February 19, 2020 Agenda

Welcome/Introductions 10:00-10:05

I/I Background and Methods 10:05-10:30

Sewer Evaluation Survey Programs 10:30-11:00

Lunch 11:00-11:15

Evaluation of Collected Information 11:15-11:35

Addressing Private Property I/I 11:35-12:00 I/I BACKGROUND AND METHODS

JERAD WEGNER, P.E. Team Leader/Project Manager Ruekert & Mielke, Inc. Infiltration

The migration of groundwater into the system via cracks in pipes and Joints Roots bricks connections into manholes Lateral connections into mainline Inflow

The direct connection of clear water into the sanitary sewer system Foundation drains Downspout connections Illegal cross connections Storm sewer directly connected to sanitary Open pick holes in manhole lid The Basics

I/I can inundate the sanitary sewer system during wet weather events and cause issues Surcharging Sewer overflows backups Understand Your Sanitary Sewer System

Public vs Private Age of System Lift Stations Surrounding Terrain Soil Conditions Only Getting Worse

Infrastructure continues to deteriorate Rainfall intensities are increasing Urban sprawl - more connections Push to do more with less budget Let’s Get Started

How does your system function during wet weather events? Lift station pumping records Latest sewer evaluation study Know where your issues are! Sewer Information Systems

Detailed maps are imperative for setting up evaluation programs Properly track where issues are located GPS has provided ability to obtain accurate locations of all attributes Geographic Information Systems

GIS has provided ability to store and access specific information regarding any attributes Enables access remotely through internet GIS Capabilities

Track cleaning efforts Track televising cycles Link televised videos and reports to their respective segment Visually show defects such as cracked pipes and active infiltration Televising Reports Into GIS

Graphically show the location of the worst defects in your system Microsoft Access database can be efficiently converted into a map format allowing the user to identify specific defect codes (NASSCO) Televising Reports Into GIS Investigation Options

Flow meters Level sensors Smoke testing Acoustic technology Flow Monitoring

Goals Actual measured system responses to rain needed to calibrate hydraulic models Quantify amount of I/I Identify drainage districts with high clearwater flows → SSES Quantify success of rehabilitation Critical information for overflow abatement projects Determine magnitude of storms that produce overflows Flow Monitoring

Keys to Successful Program Schedule to obtain adequate wet weather information Relate to rainfall intensity/duration graph for study area Carefully select manholes and flowmeter placement Level Sensors

Able to detect the depth of flow inside a manhole Cost effective, low-maintenance method Deploy many sensors throughout your collection system to pinpoint problem basins

iTracker shown Smoke Testing

Introduce smoke bomb into the collection system Observe the immediate area to see where smoke is escaping from Sewer vent pipes of house = good Dry conditions needed Acoustic Technology

Acoustic waves sent between manhole segments Sender and receiver that measure the strength of the signal and determine % blockage of line Efficiently narrow down areas within your collection system to SL RAT shown focus on – 10k-20k feet per day SEWER EVALUATION SURVEY PROGRAMS

TARYN NALL, P.E. Project Manager Ruekert & Mielke, Inc. Sewer Evaluation Survey Programs

Goal: Prioritize drainage districts for rehabilitation Flow Monitoring (Metering / SLS Run Time) Televising (Mainline & Laterals) Manhole Inspection Smoke Testing Building and Sump Pump Inspections Dye Water Testing Sewer Televising Program

Goal: Identify I/I sources and structural condition Defects Commonly Found: Cracks and fractured pipe Defective joints (offset/open) Deposits at joints or holes Root intrusion Defective service connection Sewer Televising Sewer Defects

Infiltration at Pipe Connection. Sewer Intrusion into Lateral. Sewer Defects

Infiltration at Pipe Connection to Manhole. Fractured Pipe Joint. Manhole Inspection Program

Goal: Identify I/I sources and structural condition Defects Commonly Found: Poor connection between casting/adjustment rings/cone Defective pipe connections Cracks Open joints Deposits/stains Base in poor condition Open lift holes (barrel and cone sections) Manhole Inspections Manhole Susceptible to Inflow Problems Observed During Smoke Testing

Structural Manholes Sanitary Cleanouts Sanitary Sewers and Laterals Cross Connections Storm Sewers Roof Leaders and Drains Yard and Foundation Drains Drainfields and Septic Tanks Cross Connected Storm Sewers Roof Leader and Drain Cross Connections Sanitary Sewer Defects Along Stream Broken Cleanouts and Laterals Cracked Sanitary Cleanouts, Laterals, and Manholes Side Benefits of Smoke Testing

Identifies location of sewer gases entering properties Dry traps in unused toilets, sinks, and drinking fountains Deteriorated floor drains Washing machine connections to sanitary laterals with no P Deteriorated toilet wax ring Sump Pump Inspection Program

Locate Illegal Cross Connections Foundation drain and sump pump discharge connections to sanitary sewer system Investigations of other private property sewer violations – cross connected roof leaders and yard drains to sanitary sewer system and broken or uncapped sanitary sewer lateral clean outs Enforcement – Sewer Use Ordinance Menasha Building and Foundation Drain Program

Phase 2 Phase 3 Phase 4 Properties 1,530 1,784 200 Properties Inspected 1,530 1,768 198 Identified Violations 254 413 64 Corrected Violations 252 392 64 Properties Receiving Surcharge 5 18 2 Sump Pump Cross Connections Foundation Drain Cross Connections Correction of Foundation Drain Cross Connections Sump Pump Grant Program

Corrects illegal connections from foundation drains to floor drains Provide physical connection of foundation drains to a sump pump pit to provide discharge to exterior of structure Program provides a grant to residential properties to correct illegal cross-connection City Reimburses Homeowner Entire cost if less than $500 If entire cost is greater than $500, reimbursement would be $500 + 50% of remaining balance to a maximum grant of $675 Ordinance Provisions for Private Property Surveys

Source: City of Menasha SUO Ordinance Provisions for Sanitary Sewer Lateral Repair

Section 9-3-16 BUILDING SEWERS AND CONNECTIONS If the condition of a sanitary sewer lateral is found to have major defects during the City's normal sewer inspection process, the Owner shall repair or cause to be repaired the sanitary sewer lateral within 30 days of written notification from the Department of Public Works. If the Owner does not repair the damaged lateral, the City shall repair the lateral at the Owner's expense. Major defects include, but are not limited to: 1. Cracks greater than ¼" wide. 2. Offset joints of greater than ½". 3. Any location where ground is exposed. 4. Excessive infiltration of greater than an estimated 1 gallon per minute. 5. Holes in the pipe. 6. Severe sags in the pipe where greater than ½ of the pipe is full of water. 7. Excessive Roots within the sanitary lateral. EVALUATION OF COLLECTED INFORMATION

TARYN NALL, P.E. Project Manager Ruekert & Mielke, Inc. CMAR Performance Measures

Ratio of Peak Monthly to Avg. Target % Clearwater of Total Community Annual Flow Flow City of Menasha 1.7 : 1.0 50% City of Waupaca 1.2 : 1.0 2% Town of Baileys Harbor 2.1 : 1.0 15% Village of Suring 1.2 : 1.0 15% City of Oshkosh 1.8 : 1.0 40% Evaluation of Collected Information Solutions to Collection System Management Work

Long Term – effective structural improvements and I/I reduction Cost Effective Environmentally Friendly Considerations in Selecting Rehabilitation Method

General Select appropriate methods to meet correction needs Site conditions Roadway reconstruction schedule Sanitary Sewers Uneven pipe grade Sewer and lateral construction material Time required to reinstate laterals Sanitary Manholes Material of construction will dictate rehabilitation Concrete lining reduces manhole diameter Adjustment ring seal cost vs. effectiveness Critical Components of Successful Rehabilitation

Material Selected Application Technology Applicator

* You have to have a combination of all three components for the project to be successful CIPP Defects

Bulges (Lifts) Sag in Liner Unreported Contractor Damage Pinhole Leaks Wrinkles Bad or Missed Service Reinstatement Infiltration Spotting Sanitary Sewer Infiltration Rates

Average Infiltration = Active Infiltration + Defective Joints (0.01gpm) + Cracks (0.05gpm) + Deposits (0.005gpm) + Roots (0.05gpm) + Taps (0.05gpm)

Drips = 0.01gpm (one drip per second = 0.006gpm) Manhole Infiltration Rates

Defect Average Rate Peak Rate Deposits/Stains 0.02gpm 0.1gpm Wet Walls 0.05gpm 0.25gpm Cracks/Pieces Missing 0.05gpm 0.25gpm Poor Connection Between Casting/Adjustment Rings/Cone 0.02gpm 0.1gpm Base in Poor Condition 0.02gpm 0.1gpm One Drip per Second 0.01gpm Flow Rate of Inflow Sources (a)

Defect/Source Flow Rate (b) Cleanouts 1.5gpm Building Laterals 2.1gpm Area Drains (c) 9.1gpm Sump Pumps 2.3gpm Downspouts 14.5gpm

(a) City of Tulsa information from “Control of Infiltrated Inflow” WEF, 1999. (b) Based on a 1-year 60-minute storm intensity (c) Includes patio driveway drains, etc. Inflow Through Bearing Surfaces Only Vent Hole/Pick Hole Inflow Raw Test Data for Vent/Pickhole Inflow

Table values shown are water depths in feet as measured in the receiving tank for each trial. Tests lasted one minute. By averaging the ten test trials in each column and multiplying this result by tank factor 33.5431gpm per foot of depth, the average gpm for each hole diameter is obtained. ADDRESSING PRIVATE PROPERTY I/I

JERAD WEGNER, P.E. Team Leader/Project Manager Ruekert & Mielke, Inc. Private Property I/I

The overall length of laterals can exceed the length of mainline sewers for some municipalities Significant part of sanitary sewer system that is aging at the same rate Not a very well documented part of the system PP I/I Investigation

Televise the Laterals Injection of dye water over the lateral while the televising is occurring and plug storm sewer Interior House Inspection of Basement Cross connections Sump pumps, waste and clear water Exterior Inspection of Yard Ditch Yard slope toward house foundation PP I/I Investigations

Dye water injections while televising Example of 21+ GPM leak in a single lateral PP I/I Investigations

Interior Inspections Illegal clear water connection of drain tiles directly to crock and between sewage and clear water crocks Basement floor drain, laundry tubs to crock with sewage ejector pump Basement drain tiles to clear water sump crock with interconnection to sewage sump crock PP I/I Investigations

Exterior Inspections Ponding water Slope toward foundation Ditch Cracked cleanout caps PP I/I Investigations

Extensive public outreach and campaigning is required Public more hesitant when you are working on their property Lateral Rehabilitation Options

CIPP Lining Dig and Replace Grouting at Mainline Connection and Pipe Joints Pipe Bursting Spot Repairs Franklin Example

36th Street, North of Madison Blvd 32 Houses in Rawson Homes Subdivision Constructed in the mid-1950s Oldest residential neighborhood Franklin Example

Subdivision is a 30 acres area with approximately 100 homes in the subdivision 8.8 acre area with 32 homes in the case study area Rehabilitate the laterals in 3 phases 8” mainline in subdivision had been lined previously City of Franklin within MMSD area Franklin Example

MMSD flow meters determined that excessive I/I was present in Rawson Homes Subdivision Franklin Example

Single story houses, 12 with Franklin Example

Remove and replace 12 sewage crocks and pump, vent outside at $1,650/each Plug 10 illegal drain tile connections to sewage crock, redirect to clear water sump crock at $200/each Install 11 clear water pumps in existing sump crocks at $700/each Install pressure storm lateral to road ditch, insulate at $36/LF Franklin Example

Install 10 GFCI electrical outlet for clear water sump pump at $475/each City of Franklin electrical and plumbing permits Access agreements and temporary easement agreements between City and owners Line or relay of 32 sanitary laterals at $97/lf for line and $202/lf for relay Franklin Example Franklin Example Franklin Example Franklin Example

25 laterals lined (50’-65’ long) 7 laterals relayed (50’-65’ long) 12 sewage crocks and pumps replaced 11 sump crocks and pumps replaced, with sump lines extended to ditch $237,000 Franklin Example - Results

2011 Flow Metering

Meters pulled during construction Post construction metering Franklin Example