Airport Sanitary Sewer Replacement Project


Work on the sewer system has been completed and the area is no longer an active construction zone. 

UPDATE 9/22/2021:

 The project is on track to conclude in late September. The pressurized sanitary system has been installed and old sewer and water lines have been replaced.

UPDATE 7/28/2021:

The original scope of the project was expanded, and the completion date has been extended to late September/early October.

UPDATE 6/2/2021:

Some parking disruptions are likely this week as lines are put in next to LEKTRO. Fill/Abandon Existing Structures will be done 5/31/21 through 6/4/21.

Underway May 2021

The sanitary sewer replacement project at the airport is underway and about half finished as of May 17th. This project includes the replacement of all gravity flow sewer lines with a pressurized sanitary system. This will eliminate infiltration of ground water from the Port’s system into the city sewer system. The Coast Guard portion of the airport system will be replaced at a later date. This project should cause little disruption and should be complete by mid-June.


The Warrenton-Astoria Regional Airport receives and uses, on average, 1 million gallons of water from Warrenton city per year. Currently the city of Warrenton is receiving about 5 million gallons of water per year back from AST, contributing to the already-strained capacity of the city's wastewater treatment facility. The additional water comes from stormwater and groundwater intrusion into the WWII-era AST wastewater system. The Port needs to eliminate the wastewater-system intrusion in order to help the city of Warrenton preserve and maintain their existing wastewater treatment infrastructure for as long as possible, as well as avoid surcharges that Warrenton intends to impose on the Port should the problem not be addressed.

Further, until this problem is solved, the City of Warrenton will oppose Port efforts to develop its airport industrial park, which will obstruct the potential for new lease-based revenue streams. To address these challenges, the Port contracted with A.M. Engineering in July 2020 to collect data, assess the system and provide alternatives for reconstruction or reconditioning of the system. A.M. Engineering’s study is complete. The recommendation adopted by the Port is replacement of the current system with a private pressurized sanitary system.