1st Avenue Improvements

1st Avenue Improvements: 6th Street to 9th Street

1st Avenue between 6th Street and 9th Street is undergoing total reconstruction in 2018. This is the final section of 1st Avenue that needs to be improved south of Interstate 80.


After work is complete, this stretch of 1st Avenue will feature:
  • Four through lanes and one continuous center turn lane
  • 10 foot wide sidewalks on both sides
  • Upgraded traffic signals at E. 7th Street
  • New traffic signals at 6th Street with a new four-leg intersection at 1st Avenue and 6th Street to accommodate a future connection of E. 2nd Avenue on the east leg
  • New public utilities (storm sewer, sanitary sewer, and water main)
  • Lighting and streetscaping
Finishing 1st logo


  • Bid in January 2018 IDOT letting
  • Low bid: $7,186,554.84 (Langman Construction of Rock Island, Illinois) 
  • Funding: $5.1 million of Surface Transportation Program funds, and local funds


  • Start: March 2018
  • Estimated completion: December 2018, weather permitting (driving lanes, sidewalks, and traffic signals)
  • Landscaping and final work: Spring 2019, weather permitting

Traffic Impact

  • There are traffic delays
  • Single lane traffic in both directions along 1st Avenue is maintained
  • Pedestrian access is maintained using temporary surfacing and channelizing barriers
  • Access to all businesses is maintained
  • 6th Street is closed between 1st Avenue and the Baymont Suites driveway from late April-mid September, weather permitting
  • The temporary traffic signals at the 1st Avenue/E. 7th Street intersection are removed while E. 7th Street is closed and reconstructed
  • Temporary traffic signals at the new 1st Avenue/6th Street/E. 2nd Avenue intersection provide construction access to the new E. 2nd Avenue for the Iowa Arena/UIHC Phase 2 Clinic Projects. 

Public Transit Impact

  • Coralville Transit riders may experience delays on all routes, especially during peak traffic times. Any changes to routes and schedules will be posted on www.coralville.org/transit.

Contact Us

  1. Dan Holderness

    City Engineer

    Scott Larson

    Assistant City Engineer

    1512 7th St.
    P.O. Box 5127
    Coralville, IA  52241

    Ph: 319.248.1720
    Fx: 319.248.1894

    Staff Directory
1st Ave Construction Map 2018


Maps & Documents




Weekly job meetings are Thursdays at 9:00 am at City Hall, until further notice. The public is welcome to attend and participate.

Lane Closures/Traffic Changes

  • 1st Avenue traffic is reduced to one lane in both directions the entire length of the project, from 6th Street to 9th Street (see Resources: "Phase 2 - Stages 1 and 2").
  • 6th Street west of 1st Avenue is closed between 1st Avenue and the Baymont Inn & Suites driveway (see Phase 2 – Stage 1 in Resources: "Project map and construction phases"). Information about impacted Coralville Transit routes and stops is available at www.coralville.org/transit.
  • The inner left turn lane on eastbound 5th Street approaching 1st Avenue is closed to simplify the merging of 5th Street traffic turning left onto northbound 1st Avenue. 
  • E. 7th Street between 1st Avenue and E. 2nd Avenue is closed for total reconstruction. Use E. 9th Street to access the Iowa River Landing. A construction access road connected to 1st Avenue near the railroad crossing minimizes traffic impacts from the large redevelopment projects in the Iowa River Landing.
1st Ave lanes shifted east 04.26.18
  • Southbound 1st Avenue drivers wanting to continue south through the 1st Avenue project work zone (blue path) must be in the right lane immediately after passing the I-80 eastbound off-ramp.
  • Southbound 1st Avenue drivers wanting to turn left onto E. 9th Street (black dash path) must be in the left lane immediately after passing the I-80 eastbound off-ramp.
  • Channelizing devices will separate the two lanes immediately south of the off-ramp. Both the Magellan Pipeline access and the dedicated southbound right turn lane onto 9th Street are maintained. 

Southbound 1st Avenue traffic

1st Ave SB traffic control

Current & Upcoming Work*

Work completed the week of September 10:
  • Grading for the sidewalk/retaining wall on the north side of 6th Street is substantially complete. Poured the east half of the sidewalk along the north side of 6th Street.
  • Continued pouring concrete sidewalk, banding, and subslabs south of Pipeline Road. More concrete work will happen on September 14. The concrete banding and subslabs have to be completed first in areas that will have brick pavers. 
  • Installed plantings within 6th Street raised median. 
  • Graded for sidewalk and retaining walls across McDonald’s and the adjacent vacant lot.  
  • Paved half of the future center tune lane (minus driveway openings) from Pipeline Rd north to the Cantebury BP. 
  • The solid green areas (see image) indicate completed street paving, sidewalks, and subslabs as of September 13. Note that some of the subslab areas still need brick pavers. 

Paving as of September 13

Paving Sept 13
Work expected the week of September 17:
  • Continue work on sidewalk and retaining walls along the north side of 6th Street.
  • By end of the day on September 17: Complete all sidewalk and brick paver work needed to provide a pedestrian path along the west side of 1st Avenue from 6th Street to the north side of Pipeline Road.  Pedestrian channelizers may be needed in areas where brick pavers are not complete. 
  • September 17 afternoon/evening:  Complete relocation of temporary signals to handle 6th Street traffic. Complete temporary pavement markings. 
  • Traffic change early Tuesday morning, September 18: 
    • Re-open the 6th Street connection and shift 1st Avenue traffic to the new west half of 1st Avenue south of Pipeline Road.  
    • 1st Avenue at 6th Street will have one through lane in each direction and one dedicated left turn lane in each direction. The southbound left turn lane is for Iowa River Landing construction traffic only. 
    • 6th Street will have one westbound lane, one eastbound right turn lane, and one eastbound left turn lane. A second eastbound left turn lane will be open to traffic as the overall 1st Avenue project nears completion.  
    • North of Pipeline Road, 1st Avenue traffic will still run head-to-head on the east half of 1st Avenue as work continues on driveway, sidewalks, and lighting along the west side of 1st Avenue.
  • Continue pouring driveways and sidewalks along west side of 1st Ave north of the Pipeline Road.
  • Finish the southbound 1st Ave mainline paving across Super 7’s frontage (north end of project).  
Looking ahead:
  • Phase 2 – Stage 1 completion (re-opening the 6th Street connection to 1st Avenue) is scheduled for early Tuesday morning, September 18.   
  • Phase 2 – Stage 2 completion (completes the entire west half of 1st Avenue) is scheduled for substantial completion in late September or early October.
  • The Substantial Completion Date is November 30, 2018.  This is the date when all streets, sidewalks, traffic signals, and lighting are to be complete and usable by the public.  
*Updated September 13, 2018 

Merging Traffic

How to Merge Efficiently on 1st Avenue

When traffic is slow and heavy, merging too early can create traffic backups. During peak traffic times on 1st Avenue, using a "zipper merge" can keep traffic moving and reduce traffic backups.

A "zipper merge" is when drivers use both lanes of traffic until they reach the defined merge area, and then alternate in "zipper" style into the open lane. This maximizes road space, reduces congestion, and allows both lanes to move at similar speeds.

How to "Zipper Merge"
  1. Watch for signs giving drivers notice that there is a merge ahead
  2. Stay in your lane up to the point of merge
  3. Take turns with drivers to safely ease into the remaining lane
  4. Always merge when it is safe

Merging FAQs

When is it best to use the zipper merge?

When traffic is congested and traveling at slower speeds, it is best to remain in your lane until the point where traffic can take turns merging, which is indicated by a "BEGIN MERGE" sign.

When is it best to merge early?
When traffic conditions are light and vehicles are traveling at highway speeds, it is best to merge as soon as safely possible.

Zipper Merge Resources

Take Turns sign

Pre-Project Planning

How We're Keeping Traffic Moving

To reduce traffic delays during construction:
  • Staff will monitor traffic times and adjust the timing of traffic signals as needed to help the traffic flow on 1st Avenue
  • Installed fiber optic communications at the 1st Avenue/E. 9th Street traffic signal
  • Installed pan/tilt/zoom cameras on 1st Avenue at both 5th Street and E. 9th Street, along with existing cameras at 1st Avenue/Highway 6, to remotely monitor traffic for the project corridor and beyond
  • Repositioned the traffic detection cameras at 1st Avenue/E. 9th Street to minimize false detections
  • Installed traffic detection cameras at the 1st Avenue/Interstate 80 traffic signals to replace the in-pavement traffic detection wire loops

Duct Bank NB Lane 062017

Duct Banks

In anticipation of the 
project, underground duct banks were proactively constructed in 2017. These duct banks provided places for the private utilities companies to relocate their overhead and underground facilities to be out of the way before the 2018 improvement projects. The duct banks should minimize delays caused by private utility relocations, which can be common during street projects.

Stay Informed

  1. 6th Street Connection to 1st Avenue to Re-Open on September 18

    Use caution through the work zone and watch for pedestrians, bicyclists, and construction workers Read on...
  2. 1st Avenue Construction Begins Next Phase on June 4

    1st Avenue will be reduced to one lane in each direction the entire length of the project, from just south of 6th Street to just south on 9th Street Read on...
  3. Coral Ridge Avenue Detour Begins

    Beginning Sunday evening, May 13, traffic will detour using Oakdale Boulevard, Crosspark Road, & Wheaton Road Read on...
  1. 1st Avenue Construction Begins Next Phase on April 24

    6th Street to close between 1st Avenue and Baymont Inn & Suites driveway, 1st Avenue reduced to one lane in each direction near 6th Street intersection Read on...
  2. Construction to Begin on 1st Avenue from 6th Street to 9th Street

    Northbound 1st Avenue will be reduced to one lane from just south of 6th Street to just south of 9th Street Read on...
  3. Two Major Road Reconstruction Projects Begin This Spring

    Drivers should prepare for 1st Avenue & Coral Ridge Avenue road work Read on...
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