WES Technical Advisory Team - June 25, 2026

Agenda

Facilitators:  Jessica Rinner, Civil Engineering Supervisor | Niki Davila, WES Administrative Specialist

Regional I&I Reduction Program Qualified Proposal
Clackamas Water Environment Services

Partner City: City of Milwaukie

Project Name: City-wide Sewer Rehabilitation

Date: June 5, 2026

Basin: Milwaukie

Purpose

This document presents a Qualified Proposal to the Clackamas Water Environment Services (District) to participate in cost sharing under the District’s Regional I&I Reduction Program, as outlined in the Intergovernmental Agreement Between Water Environment Services and Partner Cities for Regional Inflow and Infiltration Reduction (IGA). Under this program the District has pledged to reimburse 33 percent of actual costs to Partner Cities for Qualified Proposals, as approved by the District.

The objective of this project is to rehabilitate and restore deteriorated wastewater collection system facilities, with a specific focus on reducing inflow and infiltration, of 2355 linear feet of sewer main throughout the city. To achieve this, the project will utilize Cast-In-Place Pipe (CIPP) technology, providing a modern alternative to traditional open-trench pipe replacement methods. CIPP is a trenchless rehabilitation process that is more cost-effective, faster to implement, and significantly less disruptive to the community and environment compared to conventional sewer repair techniques. The City of Milwaukie (City) is requesting the District to review the Qualified Proposal presented here and, if eligible, provide a letter of approval to the City as described in the IGA.

Project Description

The City, in conjunction with the 2022 Wastewater System Master Plan Update prepared by Water Systems Consulting (WSC), identified pipeline mains with Grade 4 and 5 defects. Defect scores of 4 or 5 are anticipated to result in structural failure within the next 10 years, and near or exceeding the end of their service life. The CIPP Sewer lining Capital Project will restore 7 of the city’s Mainline pipe segments identified to have high PACP scores. These restorations will reduce inflow and infiltration (I&I) and facilitate long-term maintenance.

All system components are comprised of concrete pipes, either 8- or 6-inch in diameter. Additional data for the collection system is provided in Table 1, and a map of the existing system is provided in Exhibit A, both of which are included at the end of this proposal.

CCTV inspections identified several deficiencies in the system including root intrusion, cracks, sags, and mis-aligned joints. These deficiencies are presumed to be a major source of I&I in each respective area.

Remediation design is exclusively Cured-In-Place-Pipe (CIPP) rehabilitation. Ultraviolet Curing is the preferred technique for its superior performance and minimized impacts to the public.

Project Schedule

• The estimated schedule for the construction phase is August 2026 through September 2026.

Project Costs

• The estimated construction cost for the CIPP Lining Project is $1,359,000.

Exhibit A: Existing System