Most of the City's stormwater pipes are buried under our roads. Instead of assuming they need to be replaced based on their age, we use a robotic camera to view and evaluate the pipes. Pipes are selected for evaluation based on their age and the material they are made from. The robotic camera creates videos of the pipes. The videos are viewed by City staff or consultants and pipes are assigned a score based on their structural condition. 


Example of Failing Pipe

The pipes with the worst scores are severely damaged and need to be repaired or replaced. Repairs and replacements are prioritized based on the pipes locations and usage. Pipes under major roadways are the highest priority.

Learn more about pipe scoring here.

After we determine which pipes need to be repaired or replaced, we must determine the best repair or replacement technique. The following techniques are commonly used in Newcastle.

Trenchless Repair: Uses a robot or equipment to re-line the pipe. Re-lining equipment is inserted into the pipe. It pulls a liner through the pipe. The liner cures inside the pipe creating a new rigid surface inside the pipe. This type of repair is less expensive and does not require digging up the roadway. It can be used to repair small cracks and fractures in a pipe.

Trenchless Spot Repair: Uses the same technology as trenchless repair to repair a small section of pipe.

Open Cut Full Repair: Cut open the road, dig up and replace whole pipe. This is the most expensive and invasive form of pipe repair. 

Open Cut Spot Repair: Uses the same technology as open cut full repair but replaces a small section of pipe.

Learn more about pipe repair technology here. 

2018:  Began evaluating pipes in Donegal, Newport Woods and Evergreen Terrace neighborhoods. 


Map of pipes being evaluated

2019: Completed the first planned repair project in the S-038 program by repairing a pipe in the Mile Post neighborhood. Learn more about the project here.

2020: Developed pipe scoring matrix and prioritized repair work.
Project planning for the open cut repairs.

2021: Storm Conveyance Rehabilitation Project: Open cut repairs. Newport Hills area.

2022: Phase 3 evaluation of piping 2.5 miles of piping evaluation.

2023: Cured-In-Place-Piping (CIPP) 13 sections of pipes beginning of July 2023

Newcastle's goal is to continue evaluating about 2.5 miles of pipe per year. We are evaluation of the oldest piping to the most recent. We will prioritize pipe repairs as we find damaged pipes. We have evaluated three phases of piping. Total of 7.5 miles.
2023: Cured-In-Place-Piping (CIPP) 13 sections of pipes beginning of July 2023

In 2018 Newcastle received a $67,000 Flood Reduction Grant from the King County Flood Control District. This grant paid for most of the cost of the 2019 Mile Post pipe repair project.

In 2020, Newcastle received a $53,000 WaterWorks Grant. This grant is paying for repair and replacement of degrading and failing stormwater pipes.


Newcastle Mayor Newing accepts check from King County Councilmember Reagan Dunn