High Rise Bridge

I-64 Southside – High Rise Bridge Project

Project Details

Sector:
Heavy Civil – Transportation

Location:
Chesapeake, VA

Partners:
Granite Parsons Corman Joint Venture (GPC)

Project Status:
Under construction

Dewatering bag on High Rise Bridge project

Wire reinforced silt fence and tree protection

About the Project

The High Rise Bridge and I-64 Southside Widening in Chesapeake, Virginia is one of largest design-build contracts in the history of the Virginia Department of Transportation. Environmental studies concluded the need for improvements to the Interstate 64 corridor from I-464 to I-664/264 and the High-Rise Bridge in Chesapeake, Virginia. This congested corridor connects key points in Hampton Roads and is an important evacuation route for the Tidewater region.

The major heavy civil highway project encompasses almost nine miles of I-64. By project completion, major improvements will include:

a new fixed span bridge standing 100-feet over the Elizabeth River
a replaced Great Bridge Boulevard Bridge
six additional bridge widenings plus asphalt overlay on each
nine miles of interstate widening including an Express Lane in each direction
area drainage improvements

The new High Rise Bridge will be built just south of the existing bridge. Once the new bridge is opened, westbound drivers will use the new bridge and eastbound drivers will use the existing bridge.

The project delivery is a design build, led Granite Parsons Corman (GPC) Joint Venture. Under this method, the GPC performs final design, right-of-way acquisition, utility relocation, permit acquisition and construction. This approach allows some of these activities to be done concurrently.

Erosion Control Challenges and Solutions

Erosion control was a critical focus for the entire project. This stretch of I-64 is surrounded by wetlands and the Chesapeake Bay watershed. Additionally, a project of this scale requires a high volume of land disturbance which also challenges erosion control and stormwater management.

The GPC Joint Venture was proactive about implementing both state (VDOT) standards and innovative erosion control and stormwater practices.

Slope Interruption for Runoff from Impervious Surfaces

Linear highway projects like the High-Rise Bridge have high volumes of impervious paved surfaces. Those paved surfaces are separated by a median that is continuously under construction and thus subject to erosion.

During the I-64 lane-widening, traffic lanes were shifted, and jersey barriers were installed to protect drivers from the active work zone.

Problems arose after heavy rainstorms washed runoff under the jersey barriers and into the median. As runoff flowed from roadway to median, rills began to form which threatened the slope’s stability. Left untreated, the runoff rills would have undercut the road and damaged the highway.

Compost Filter Sock for slope interruption

To mitigate the erosion, we recommended GPC incorporate a Compost Filter Silt Sock slope interrupter to dissipate the sheet flow from the impervious road.

A slope interrupter is a tubular product that is installed midway up a slope. The slope interrupter dissipates the velocity of sheet flow and absorbs sediment laden runoff before it travels further down the slope.

Erosion control wattle for slope interruption on High Rise Bridge Chesapeake

Slope interrupter on High Rise Bridge project

We recommended MKB’s 18” Compost Filter Silt Sock for the project. The 18” erosion control wattle was installed in a hand dug anchor trench that ran alongside the highway, halfway up the median slope. A skid steer helped install the 55-foot sections of Silt Sock which was anchored to the slope with oak stakes.

At the end of this phase, GPC cut open the Compost Filter Sock. Since the fill material is all natural shredded hardwood, the mulch remained on site and the netting was removed.

High Performance Silt Fence for a High Water Table and Wetlands

The GPC team installed our 400EO Silt Fence for sediment control and wetland delineation on the High-Rise Bridge Project. 400EO Silt Fence is a monofilament silt fence that was added to VDOT’s Approved Materials List in 2021. GPC chose to use this heavy-duty silt fence for several reasons including:

400EO meets and exceeds VDOT’s criteria for silt fence standards
the 2-inch bright green delineation line at the top of the silt fence allowed GPC to use the temporary fence for delineation in wetlands
the monofilament silt fence demonstrates greater performance for filtering sediment laden runoff (compared to standard slit film fences)
the monofilament yarns are strong and UV resistant, resulting in a long service life on a major highway projects

Geotextiles and Geogrid Support Road Construction

High strength silt fence was not the only geotextile utilized by GPC Joint Venture. Geotextiles and geogrids were supplied for numerous applications across the highway project.

One of those critical applications was the road approach for the new High-Rise Bridge. Before road reconstruction could begin, countless loads of fill were placed in the area that would become the road approach. After the fill was dumped, an AASHTO approved woven geotextile fabric, was installed for subgrade stabilization and biaxial geogrid was installed in areas that required more structural support.

The bi-axial geogrid and the 200-pound woven geotextile fabric were also used to stabilize the access roads that gave heavy equipment and cranes access to the site of the new bridge.

Erosion Control Blankets Stabilized Slopes and Soil

The High-Rise Bridge project utilized a combination of temporary and permanent erosion control blankets for different areas on the highway expansion.

Single Net Straw Matting was the primary temporary erosion control blanket.

For some ditches, channels and steep slopes, the GPC Joint Venture team required a rolled erosion control product with improved performance and greater longevity. For those more sensitive areas, GPC installed 100% Coconut Blanket. We recommend Coconut Erosion Matting for the severe erosion areas because it is easy to install, aids in vegetative establishment (a concern in the hot and humid Virginia summer months) and can handle greater stress than straw-based erosion blankets.

Elsewhere on the project, Recyclex Turf Reinforcement Mat was used for highly sensitive areas that were subject to severe erosion.

Additional Products on the High Rise Bridge Project

Heavy civil highway projects can last for years. As the site goes through different phases, different geotextiles, stormwater products and erosion control solutions are needed.

Additional products supplied to the High Rise Project included: