State Route 99/Eaton Road Interchange Improvement Project


Image of the project layout. The legend identifies areas of paved surface, truck apron, hard surfacing, landscape area, and sidewalk. The roundabout connects the following roadways: Hicks Lane from the north, Eaton Road from the east, north bound State Route 99 exit ramp from the south, Eaton Road from the southwest, and the State Route 99 north bound entrance ramp from the northwest.

Project Description

This project will convert State Route 99 (SR 99) North Bound (NB) ramps at Eaton Road and Hicks Lane into one multilane five-leg roundabout intersection. Although the two intersections will be combined, the local circulation and access will remain unchanged.

The primary purpose of this project is to improve safety for all travel modes at the SR 99 NB ramp intersection and Hicks Lane intersection with Eaton Road. The secondary purpose of this project is to improve operations, reduce delay, and enhance mobility for all travel modes at the intersections.  Construction will phased in order to maintain local access to SR 99 and to the properties adjacent to Eaton Road and Hicks Lane.

View the Pre-construction Video

Construction Detours

Beginning August 9th 2021 and continuing through early 2022, the following road closures and detours will be in place.

You are encouraged to build extra time into your schedule and plan alternate routes to avoid the intersection.  We realize this will pose a temporary inconvenience and appreciate your cooperation and patience during this time. Businesses and residents will have access to their properties at all times.

Detour A

SR99/Eaton Northbound Off Ramp – Closed Monday – Friday evenings from 9pm to 6am

Detour B

SR99/Eaton Northbound On Ramp — Closed 100% day and night until further notice

Detour C

Eastbound Direction of Eaton Overcrossing — Closed Monday - Friday evenings from 9pm – 6am

Construction Details

Notification of Construction Activity


This project is funded with a combination of federal Highway Safety Improvement Program (HSIP) funds, State Highway Operation and Protection Program funds, and Local Agency match funds. Construction is estimated to cost approximately $5 million.

Public Outreach

Updated Road Closures - 12/6/2021

Press Release - Start of Construction

Eaton Newsletter - April 2019

Plans and Specifications


Bid Book

Project FAQs

Why build a roundabout at this intersection? The assessment of this project’s safety needs included an Intersection Control Evaluation, and professional analysis deduced that a traffic signal would not solve the current safety issues. In addition, it would increase the costs related to the project, as a traffic light would necessitate the widening of both the off-ramp and the Eaton Road Overcrossing. Also, to maintain safe traffic flows, a traffic signal would have ultimately required a closure of Hicks Lane.

Why is this project important to the City? This project is specifically identified as a safety project, meaning that there was an identified issue with traffic flow that needed to be addressed. The funding for this project is specific to the safety needs that have been identified. One of the components of this project does include the grinding and resurfacing of Eaton Road within the construction area, which will provide a smooth driving surface to motorists approaching and using the roundabout.

What delays should motorists expect? Various detours and lane closures are part of the construction process of this project. The City has worked with our area partners such as Chico Unified and CARD to address facilities and transportation routes that may be affected. There are three major detour plans that are part of this roundabout project, and specifically, the Northbound 99 offramp at Eaton Road will remain open during daytime hours for the entirety of this project. Two additional detours have been identified. We understand that these construction projects and lane closures do create delays to our community traveling in the area, and we ask for their patience, as this project will greatly improve traffic flow in the area once completed.

Environmental Clearance

CEQA Notice of Determination

NEPA Categorical Exclusion

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