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NW 70th Avenue Improvements

Major improvements to NW 70th Avenue from the west city limits to NW 86th Street are underway. Improvements include widening the road to four lanes with a median, roundabouts as intersection control at three locations, and the addition of a bike trail from NW 86th Street to connect to the Grimes trail. 

Status Update:

All lanes on NW 70th Avenue and NW 100th Street will open to traffic on December 9 at 9 am.  We thank you for your continued patience during this busy construction season. Please be cautious as crews continue work in the area. Phase two construction on NW 70th Avenue will begin in the Spring of 2018.

Click on this link to watch a video on the correct way to drive through a roundabout.

Presentation given at the public meeting on March 3, 2016

Click here to see overall map and plans for NW 70th Avenue.

Phase I - NW 98th Street to NW 107th Street

Estimated Cost:  $7,361,434.50

Estimated Road Construction Start Date:  Spring 2016

Estimated Completion Date: December 9, 2016

Contractor for Upcoming Roadway Improvements:  Alliance Construction of Grimes, Iowa

Engineer:  Foth Infrastructure & Environment, LLC

City Staff Project Contact:  W. David Cubit, Public Works Director, 515.278.0822

Phase II - NW 86th Street to Peckham Street, bid in the winter of 2017 and constructed in 2017 and 2018. The road will be closed to through traffic during construction.

Estimated Cost: Currently being determined.

Estimated Start Date:  Fall 2017

Estimated Completion Date:  Fall 2018

Contractor:  Yet to be determined

Engineer:  Foth Infrastructure & Environment, LLC

City Staff Project Contact:  W. David Cubit, Public Works Director, 515.278.0822

Project Status: Preliminary design phase

Phase III - Asphalt overlay of roadway between Peckham Street and NW 98th Street after completion of Phase II. There will be intermittent closures during construction.

Estimated Cost:  $830,000.00

Estimated Start Date:  After completion of Phase II

Estimated Completion Date:  Undetermined

Contractor:  Yet to be determined

Engineer:  Foth Infrastructure & Environment, LLC

City Staff Project Contact:  W. David Cubit, Public Works Director, 515.278.0822

Project Status: Preliminary design phase.

NW 70th Avenue.JPG

There will be no property owner assessments as part of Johnston’s project.  A thorough traffic study of the corridor was performed and concluded that a series of three roundabouts handles existing traffic and future increases in traffic.

Click here to learn more about roundabouts and why they're being chosen as the safest method for intersection control on some Johnston streets.

Current traffic on NW 70th Ave is 13,000 vehicles per day.  By 2035, traffic is projected to grow to 20,000-26,000 vehicles per day.  The proposed design accounts for this increase and concludes that acceptable levels of service will be maintained through 2035.

The impetus for the entire project is to be ready for the high school that will be built nearby and to address current and future traffic as the area continues to develop. This project will no doubt be a significant project for the City of Johnston. We couldn't do it without your input and patience.

We want to keep you informed every step of the way, so we are building an e-mail database.  Your e-mail will not be shared with anyone. If you would like to get on the list, please e-mail us here.

We encourage you to also "like" the City of Johnston Government Facebook page and also follow us on Twitter @cityofjohnston. We will provide frequent updates there and here on our website.  Click here for the latest updates. 

If you ever have any questions about the improvements, please feel free to contact
Public Works Director Dave Cubit.