Three Ways to Rebuild a Highway While the Traffic Keeps Moving

When you rebuild a busy highway, you need somewhere for traffic to go and ground that can support the changes. Your success depends on how carefully you select a method based on detour capacity, available space and soil conditions. Here are three reliable options you can use to rebuild highways while traffic keeps moving.

1. Close the Highway and Reroute Traffic While You Rebuild

If you have suitable alternative routes, you can close the main highway entirely and redirect traffic to them. This approach gives your team complete access to the work zone, which can speed up construction. However, you must first analyze whether the other routes can handle the extra traffic. You’ll need to set up clear detour signs and communicate with the public well in advance of the closure.

For example, when Cianbro replaced Maine’s Veranda Street Bridge in April 2022, they closed the highway for 60 hours and used self-propelled modular transporters to move the new bridge into position. However, much of the preconstruction work happened before the closure window. You should identify which tasks you can complete before the closure and which must wait until all traffic is rerouted.

Build Beside the Highway Without Shutting It Down

If closing the highway isn’t practical, you can build new lanes or structures right alongside the active roadway. Selecting the best retaining wall solutions for highway construction is essential when expanding the road in this way. You should confirm that the ground can support the extra weight and consider whether nearby communities may face construction or traffic noise levels approaching 85 decibels, the point at which sound can become harmful with prolonged exposure.

For example, Geoquest USA highlights a project on Oahu’s H-1 Freeway, where crews used their Mechanically Stabilized Earth (MSE) technology to support a shoulder-widening project with reinforced earth walls. These walls stood 10 feet tall and stretched about 500 feet.

In that case, the team chose low-density cellular concrete for backfill, which weighed about 70% less than typical select granular backfill and helped address foundation settlement concerns.

Split the Highway in Half and Shift Traffic as You Go

A common approach is to move all traffic to one side of the highway so you can reconstruct the opposite side, then switch. To use this strategy safely, you must evaluate if your temporary lane shifts and barriers can handle traffic volumes, especially during peak times. Ensure your setup keeps both motorists and workers protected.

Lindsay highlights the Florida ABC Acceler8 initiative, where crews rebuilt eight bridges using a movable barrier system called the Road Zipper. This system lets you adjust the number of open lanes in each direction throughout the day as traffic patterns change. Solutions like this can make your project more efficient, but only if your highway width and traffic needs allow for it.

Frequently Asked Questions

Here are answers to commonly asked questions about keeping a highway rebuild from shutting down a region.

What are the best retaining wall solutions for highway construction?

The best retaining wall solution depends on your site’s foundation capacity, available space and loading needs. For highway widening, an MSE wall with lightweight backfill may be a strong fit when you need to support new lanes without adding excessive weight, such as with the Geoquest USA example. Your design team should compare wall type, backfill weight and soil conditions before choosing a solution.

Does a short highway closure mean the entire rebuild happens in that window?

No. A short closure usually covers only the work that requires traffic to stop. In Cianbro’s Veranda Street Bridge example, crews prepared the replacement structure before moving it into position during the closure. When planning your schedule, separate advance construction, closure-dependent work and post-reopening tasks.

Why should you evaluate traffic staging and retaining wall design together?

You should evaluate them together because your traffic plan determines where vehicles need to go, while retaining wall design helps determine whether that temporary or permanent alignment is feasible. A staging plan may look workable on paper, but it still needs enough space, foundation capacity and ground support to keep each construction phase safe.

Let Your Site Conditions Guide Your Decision

You should always weigh the pros and cons of a concentrated closure, building alongside active lanes and staged lane shifts using real data from your project. Bring your geotechnical assessments, traffic analyses and site access plans together early in your process. Before you lock in your schedule, confirm that your team can prove both a safe traffic route and a reliable ground support system for each stage of construction.