The N.C. Department of Transportation and the Federal Highway Administration agree that the Preferred Alternative for the proposed project is the
Hybrid 6/8-Lane Widening Alternative. It involves widening I-26 to three lanes in each direction between U.S. 25 and the I-26/U.S. 25 (Asheville Highway) interchange. It also involves widening I-26 to four lanes in each direction from the U.S. 25 (Asheville Highway) to the I-40/I-240 interchange.
The Hybrid selection is a result of a thorough review of the results of an impact assessment for three widening alternatives documented in the project’s
Draft Environmental Impact Statement. The decision was also based on an assessment of the comments made on the Draft Environmental Impact Statement by local governments, government agencies, non-government organizations and the public.
The Hybrid 6/8-Lane Alternative is the Preferred Alternative because it meets the project's purpose and need of reducing congestion and it has the fewest impacts to the community and environment. The Preferred Alternative was also identified as the Least Environmentally Damaging Practicable Alternative by environmental agency partners.
U.S. 25 Interchange
During an October 2016 public comment period, NCDOT heard concerns from the public that proposed interchange improvements at U.S. 25 (Asheville Highway, Exit 44) would result in a footprint that had too many impacts to homes and businesses.
NCDOT chose to build a
diverging diamond interchange after studying two design possibilities that would reduce the footprint – the other being a synchronized interchange.
By comparison to the previously proposed interchange, shown at the public hearing in October 2016, the revised diverging diamond interchange reduces the number of buildingfrom 11 to 0 and the number of impacted parcels of property from 41 to 11. It also has fewer impacts to streams, wetlands, and natural communities and has a reduced cost.
U.S. 64 Interchange
During the public comment period in October 2016, NCDOT also heard concerns from citizens and local officials that the U.S. 64 interchange with I-26 (Exit 49) needed improvement.
After studying the interchange, NCDOT decided to upgrade it to a design called “Partial Cloverleaf B with Enhanced Left Turns” to improve traffic flow through the interchange. This design will keep two of the existing loop ramps to exit I-26 and make all exiting vehicles turn right onto U.S. 64 from the freeway exits. This design will also create opposing left-turn lanes upstream of the interchange for traffic turning onto I-26.
These lanes are designed to more efficiently move all traffic patterns through the interchange. This design also provides accommodations for pedestrians and bicyclists on U.S. 64 through the interchange.
I-26 Bridge Over the French Broad River
I-26 will be widened to four lanes in both directions from U.S. 25 (Asheville Highway) in Henderson County to I-40/I-240. This stretch includes the two bridges over the French Broad River that will be replaced with one span. Before construction begins, it’s necessary to determine how the new bridge will be built and how the old bridges will be removed. To build the new bridge and demolish the old ones, NCDOT will causeways in the river.
It is also important for NCDOT to implement safety procedures and alternatives for river-goers during the project. None of the construction or demolition will have an impact on safety or usage downstream of the bridges. NCDOT will provide a “safe passage lane” in the water for river users that will include floating navigational aids to reduce the risk of accidents. NCDOT will also require the contractor to install a catchment device on the structures to prevent construction material from falling in the water.
While developing these initial safety plans, NCDOT found that there is no easy way to provide portage around the bridge. The closest public pull-out is at Bent Creek River Park, about a mile upstream of the bridges. From there, boaters would then drive about 6 miles north on N.C. 191, to reach the next public put-in at Hominy Creek River Park. NCDOT also found that it could be possible to provide a pull-out and put-in at the bridge, This, however, would require users to walk through an active construction zone. Providing a safe passage lane for the duration of construction is a safer and more reasonable option.
NCDOT recognizes that boat trips can begin well upstream, as far as the headwaters in Transylvania County. Public access points are at Westfeldt Park and Horseshoe Park in Henderson County and at Bent Creek River Park in Buncombe County. Working with appropriate partners, NCDOT will place signage at boat access locations to alert river users to the construction downstream. NCDOT will also advise the public through other means, such as its website and social media.
Hydraulics experts have examined how the causeways will affect river levels and depth and determined that there will be minor impacts. With the temporary causeways in place, the river level will increase approximately 10 inches during a 100-year storm event, and that would have no new impacts to existing structures. This rise will decrease with distance. There is no anticipated flooding downstream of the bridge.