PROJECT DETAILS

This project is one of many projects identified in the Inflow and Infiltration (I & I) Program.  Inflow and infiltration are when stormwater and groundwater enter the sanitary sewer system.

• Inflow comes from stormwater collectors (such as catch basins and roof gutters) that were connected to the sanitary sewer system prior to current regulations that no longer allow it. 
• Infiltration comes from groundwater entering sewer pipes and manholes through breaks and cracks.

Both inflow and infiltration can cause the sanitary sewer to overflow, during heavy storms, which affects public health and safety.

Through this project, sanitary sewer main lines (large publicly owned sewer pipes in the street) will be rehabilitated and repaired as priority repairs, due to the current conditions of these systems. This will correct I & I issues in the areas along 5th Street (between John Adams and Monroe Streets) and the areas bounded by 7th, 9th, Jackson, and Taylor Streets. While this project addresses I & I repairs, the separate 2025 Roadway Resurfacing Project repaired and repaved Harrison Street (between 7th and 9th Streets) after the Rivercrest 4 contractor replaced  the Harrison Street sewer laterals. Replacing these laterals in advance, allowed the I & I program to address issues in this area now, rather than waiting for the pavement moratorium to expire. 

To carry out these repairs, various construction methods will be used according to the rehabilitation needs and unique characteristics of each site, such as the type of land (rocks, landscape) and the proximity to structures. Some of the methods include pipe bursting, open trench installation, horizontal directional drilling, and closed-circuit television (CCTV). 

• Repairing approximately 1,100 linear feet of sewer mainline, via Cured-in-Place-Pipe (CIPP) lining construction method. This method utilizes special chemicals that harden on the pipe rather than tearing the pipe from the ground.  
• Replacing approximately 150 linear feet of sewer mainline using the pipe bursting construction method. This method limits the need for a lot of excavation (digging). 
• Replacing approximately 750 linear feet of sewer in place, via open trench method. These will be repaired as "sewer in place" meaning the lines will not need moved or relocated to accomplish the rehab work. The open trench installation method helps accomplish this.   
• Installing approximately 200 linear feet of new sewer pipe, using the horizontal directional drilling (HDD) method as this option uses limited excavation minimizing the disturbance to the ground.  
• Inspecting approximately 98 sewer lateral lines and repairing or replacing those in poor condition.  These types of lines connect private homes or businesses to the public sewer system and are often referred to as “plumbing pipes. ” To address these lines, cured-in-place (CIPP) lining construction method will be used which utilizes special chemicals that harden on the pipe rather than tearing the pipe from the ground. Pipe bursting and open trench installation will also be used.  
• Fully restore Taylor St. (7^th to 9^th Streets) and Monroe Street (5^th to 6^th Street) by grinding off the top 2-inches of the roadway and repaving across the entire width of the road. 

What to Expect During Construction

Approved construction days are Monday through Friday. 

• Brief sewer service interruptions will occur. You will receive a door notice 1-3 days in advance of these impacts.
• On-street parking restrictions at designated times.
• Temporary staging or storage of construction materials and equipment.
• Noise, vibration, dust.

hoW CAN i GET MY LATERAL LINE REPAIRED? 

A key strategy for removing Inflow & Infiltration (I&I) is addressed in the City's Lateral Program. Through this program, eligible property owners may receive free sewer lateral line inspections and free lateral line repairs or replacements.  The inspections will be offered during construction and restorations will be provided, free of charge, for applicable property owners if inspections reveal problems with the lateral lines.  The city will pay for repairs of the portion of lateral to within 5-feet of the home), along with any landscaping, patio, sidewalk, or other hardscaping that is disturbed by the repairs – eligible program participants will not be billed for this work! 

Eligible property owners have been identified and mailed Right of Entry and Access Forms.  Signing and returning this form is all that’s needed to sign up for the program!

If you have not received a form and believe you should have, need a replacement form, or have any questions about Lateral Program in general, please contact the project manager, Kenneth Cannady-Shultz . 

Right-of-Entry and Access Forms will be accepted up until construction begins. There will also be opportunities to sign up during construction. If you want to participate in this Program, you still have time to submit the form. The sooner you submit, the more likely the City will be able to honor any special requests or accommodations included in the form.

i & i dictionary

This project is part of Oregon City’s Inflow and Infiltration Program (I&I Program) - a program created to address stormwater and ground water entering the city's sanitary sewer system.  To understand the I & I program and this project, several key terms are defined: 

Groundwater is a naturally occurring source of water located below the ground’s surface. It can be impacted by stormwater (rain, snow) that soaks into the ground filling the tiny spaces between rocks, sand and dirt under the surface. Groundwater levels fluctuate throughout the year as the seasons become more wet (high groundwater level) or dry in the summer (low groundwater levels). It’s like water hiding in a sponge, but underground! 

Infiltration happens when groundwater leaks into the underground public sewer system through cracked pipes, broken manholes or improperly connected roof drains. Infiltration increases during winter and spring when groundwater levels are high. This increase can overload the sewer system, leading to backups and system failures. Because this additional water must be treated at the wastewater treatment plant, it increases costs for both the city and utility customers. Oregon City utilizes the Clackamas County Water Resource Recovery Facility, which is designed to handle higher flows. 

Inflow is when surface stormwater enters the sanitary sewer system through direct connections such as downspouts from roofs, sump pumps, or improperly connected stormwater pipes. Inflow can significantly increase flows during rainstorm events - potentially overloading the sewer systems and leading to sewage backups. Like infiltration, inflow raises treatment and maintenance costs, while placing additional strain on wastewater facilities. More critically, it threatens both environmental and public health. Inflow is the primary cause of peak surges in sewer flow during storm events.  Oregon City currently experiences high levels of Inflow due to old stormwater collectors that were connected to the sanitary sewer system before codes changed which is no longer allowed. During the winter and spring, most flow in the sanitary systems comes from Inflow and Infiltration (I & I). However, newer sections of the City’s system have very low levels of I&I year-round.

Lateral Lines (laterals) - Sewer laterals are small pipes that connect a home or business to the public sewer system. These pipes carry wastewater or stormwater away from the buildings into the public mainline sewer systems which then transport it to the city's wastewater treatment facility for processing.  Typically, each home or business has a single sewer lateral.  In Oregon City, maintenance of sewer laterals is divided between the property owner and the City.  The City is responsible for the section of the lateral line that runs from the public mainline to the back of the sidewalk (in most cases). The property owner is responsible for the section that runs from the edge of  the (if the sewer main is under the road), or from just past the connection point between the lateral line and the sewer main More information can be found in the City's Sanitary Sewer Lateral Policy. For properties that are eligible for the  City's Lateral Program, the City will pay for repairs or maintenance.

Main lines are large pipes within the city's water, sanitary sewer and stormwater sewer systems designed for higher volumes. Sewer mainlines connect to the (smaller) lateral lines to transport wastewater to pump stations or treatment plants to remove contaminants. 

Manholes are below ground structures used to access the City’s sewer systems for inspections and maintenance. You can identify manholes by the large round metal lids typically found within the roadway. Manholes are also used to change the direction of sewer pipes (like turning a corner); shift pipes from one side of the road to the other, or to combine flows (from two or more pipes into one main pipe (done for sanitary and storm sewer systems). 

Public Right of Ways (ROW) are portions of land dedicated for use like sidewalks, roads, and access to public utilities (such as water, sewer, etc.). Government agencies (city, county, state) are responsible for maintaining and managing these spaces. Think of it like the Oregon City Public Library. The city (government) owns it, but everyone can use it, and the city workers are like janitors who keep it clean, safe and working properly. The ROW is a shared community space and is protected by important rules and regulations. 

Rehabilitation (Rehab) restores the current system by improving the conditions to help make them last longer.  I & I rehab restores existing sewer pipes or manholes, at their current locations, using different construction methods. Rehab improves the conditions to help make them last longer. 

Repairs, unlike rehabilitation, are long-term solutions.  These can include full pipe replacements, new paving, etc. For the I & I program, repairs fix the system by removing most (or all) existing sewer pipes or manholes and replacing the removed portions with brand new materials using pipe bursting and trenching construction methods. 

Sanitary sewer lines are underground pipes that carry wastewater away from buildings (homes, businesses, etc.), to be treated at a treatment plant. 

Sewage is a type of wastewater that typically contains human waste. Oftentimes the term sewage and wastewater are used interchangeably but not all wastewater contains sewage.  

Sewer Systems consist of all the parts that make up the city's sanitary and stormwater collection systems. These include pipes, manholes, and pumps that are maintained by the city to transport different types of water (stormwater and sewage). Note: Sanitary Sewer Systems and Stormwater Sewer Systems are two different collection systems. 

Stormwater is rainwater that flows into gutters and the stormwater sewer system. As the water runs off rooftops, streets and other hard surfaces, it can collect dirt, oils, and debris, becoming polluted. To help clean this runoff, the city uses specifically designed raingardens, ponds, planters and other structures to treat the water before it releases back into the environment.

Stormwater collectors collect rainwater or channel rainwater. Examples include catch basins and roof gutters. 

Treatment is the process to remove pollutants from wastewater to make the water safe for reuse or release into the State’s waterways.

Wastewater is a combination of sewage and dirty/used water from toilets, sinks, washers, showers and other household or commercial sources. This water travels through the sanitary sewer system - which includes lateral lines and main lines - to a treatment facility.  

Wastewater Treatment Facilities (also referred to as "wastewater treatment plant" or "sewage treatment plant") are the locations where wastewater is treated (cleaned) to remove harmful substances (like human waste, chemicals, and food scraps). Once cleaned, it is safe enough to be sent back to the natural water cycle (usually into rivers or oceans) or be reused for things like irrigation.  

MAPS

• MCLOUGHLIN BASIN 1 MAPS

DOCUMENTS

• LATERAL LINE PROGRAM RIGHT OF ENTRY LETTER & FORM - SAMPLE
• June 26, 2025 Harrison Street Mailer
• Right of Entry Letter and Form Sample

WEBLINKS

• Inflow and Infiltration Reduction Program
• Lateral Program
• Current I&I Program Activity
• 2025 OC Roadway Reconstruction Project PMUF