Browns Valley Trunk Project

For current Browns Valley Project construction information, click here.

What is the Browns Valley Trunk Project?

Wastewater from the Browns Valley area and Southwest Napa currently flows through the sewer pipelines to the West Napa Pump Station on its way to the treatment plant.  The Browns Valley Trunk Project is designed to intercept this wastewater and divert the flow away from sewer lines that are over capacity via a new pipeline that will deliver the wastewater to NapaSan for treatment.  

Why is this project necessary?

This project is essential to reduce the potential for sewer overflows and is necessary for the operation of our sewer system. The sewer pipes in Southwest Napa are over capacity in many areas, meaning that these pipes are in danger of overflowing when there are high flow events, such as a large storm.  Sewer overflows can result in untreated sewage getting into storm drains and flowing to creeks or the river, which is bad for both human and environmental health.  The Browns Valley Trunk project is designed to divert flow from sewer lines that are over capacity. 

When and where will construction be taking place?

Construction will begin in late spring 2020 and continue through fall of 2021.  All work will be done in compliance with the Construction Site Requirements set forth in the Napa County Shelter-in-Place Order to ensure worker safety. The map below shows the project area.

Proposed Browns Valley Trunk Sewer Alignment

Will there be a community meeting where I can learn more about this project?

Our community meetings scheduled for April had to be cancelled due to the COVID-19 pandemic.  We created the informational presentation at the bottom of this page to give greater project detail and answer any questions you may have.

Where is construction currently happening?

To get the latest construction location information, visit our Construction Zones web page.  

Do you want to receive email updates regarding the Browns Valley Trunk Project?

To receive emails regarding the status of the Browns Valley Trunk Project, sign up here.


If you have further questions concerning the project, please call the project hotline at (707)540-9964 or email

Browns Valley Project Documents