Based on feedback from the August 2020 Virtual Public Information Meeting, the following major revisions were made:

(1) Corley Mill Road was relocated behind the TD Bank Administration building to a new location intersection along US 378 across from the Honda Dealership. This removes Corley Mill Road from its current tie-in location at the intersection of Ginny Lane.

(2) Riverchase Way was realigned along the existing Corley Mill Road alignment to tie into a new intersection with Corley Mill Road adjacent to the Corley Mill Plaza.

(3) Various lane assignments were updated throughout the corridor.

(4) A shared-use path was added along the northern edge of US 378 Eastbound for bicyclists and pedestrians.

Riverchase Way would be realigned along the existing Corley Mill Road alignment to tie into the new signalized intersection at Corley Mill Road adjacent to the Corley Mill Plaza. Traffic traveling towards US 378 will have a dedicated free flow right turn lane at the traffic light.

Currently, traffic from US 378/Ginny Lane/Corley Mill Road converges at one signalized intersection, creating long wait times and traffic congestion due to the high traffic volumes and number of traffic movements that need to be accommodated.

The new design, while adding signals, will distribute traffic from one main intersection to multiple intersections, each with a reduced number of signal phases thus allowing more green signal time for both US 378 and the new M2 (relocated Corley Mill Road). This design reduces the number of traffic movements that need to be accommodated at each intersection, provides more capacity through the study area, and better manages traffic congestion/queuing resulting in reduced network delays. In summary, reducing the number of signal phases will increase the “green time” for all legs of traffic.

The proposed improvements will not directly increase the existing traffic volumes but will help traffic flow more efficiently and reduce congestion along US 378 and Corley Mill Road. In addition, it will provide easier and safer entrance and exit to Riverchase Way, addressing a public concern from the 2020 public meeting.

The table below summarizes the Level of Service (LOS)* at the intersection of US 378 and Corley Mill Road in the year 2045 for the two alternatives discussed above. The existing condition and “No Build” (2045 projections if no project is constructed) are shown as a baseline.

* Level of Service is a measure of drivers’ experience on the road. Sections of roadway are scored based on speed, traffic delay, safety, and maneuverability. LOS rankings are comparable to grades in school; where “A” means traffic is flowing smoothly with no congestion and “F” means significant traffic delays and congestion.

The "Ultimate Corley Mill Gateway Project" is comprised of several phases including the recently completed Ginny Lane intersection improvements and the I-20 exit ramp reconfiguration. The Sunset Split has been identified as the next phase of the Gateway Project, which will be followed by the Bypass.

The previously proposed Bypass was considered as a component to multiple alternatives in the 2022 Traffic Improvement Study. This Bypass was a two-lane roadway that began across from Corley Mill House, curved behind Woodridge Memorial Park, and tied into a new location intersection with Riverchase Way near Royal Oaks Lane. It then crossed I-20, and intersected US 378 at the current Davega Drive intersection. As a standalone project, the Bypass would not adequately address PM traffic, so it would not satisfy the Purpose and Need of the project. The Town of Lexington is actively working to identify funding to complete the Bypass.

Extending Ginny Lane to connect with Mineral Springs Road has been conceptually considered in the past; however, this would not address the Purpose and Need of this project and would need to be pursued as an independent project. Future improvements along Ginny Lane and Mineral Springs Road have been identified in the Town's Long-Range Transportation Plan. Funding for these projects has yet to be identified.

Improved access for residents and businesses along Darby Ambrose Road and Park Place Trail at US 378 is being actively investigated by the Town.

The Town is aware of the concerns regarding left turns from Park Place Trail and is analyzing alternatives to ensure appropriate entrance and exit through improvements to the corridor.

The Town is coordinating with residents along Darby Ambrose Road to determine the best alignment to minimize impacts to existing property owners and ensure appropriate access to US 378.

The Town, in cooperation with Lexington County, is actively considering new sites. The goal is to find a location to conveniently service existing customers.

The Sunset Split will maintain all existing sidewalk along the southern edge of US 378, as well as all existing sidewalks along sideroads throughout the corridor. A 10’ shared-use path for bicyclists and pedestrians will be constructed on the northern edge of US 378 Eastbound. As part of the Town's Long-Range Transportation Plan, all other roads are being designed to allow for the accommodation and expansion of a future bicycle/pedestrian network. Bike lanes will not be included in the project.

The project team will work with Lexington County Emergency Services to develop a suitable path forward to maintain appropriate response times.

The Town of Lexington, in coordination with the SCDOT, is proposing to restore the Park-and-Ride within the existing right-of-way adjacent to its current location.

At the intersection of relocated Corley Mill Road with US 378 eastbound, there are three (3) lanes – two of these lanes are restricted to left turns only, while the far-right lane is for left turns or continuing straight into Honda of Columbia. For traffic traveling from Corley Mill Road to Ginny Lane, vehicles should utilize the far-right lane at the terminus of Corley Mill Road which will place them in the far right lane of US 378 eastbound. From there, vehicles can easily enter the dedicated right turn lane onto Ginny Lane.

Traffic exiting from I-20 westbound currently has direct access to turn onto Corley Mill Road; however, traffic frequently backs up onto I-20 particularly when River Bluff High School releases students in the afternoon. While the recently completed I-20 Westbound Exit Ramp improvement project reduced some of the back up on the exit ramp, it is not realistic to eliminate this congestion while maintaining Corley Mill Road at its current location.

The Sunset Split project has a dedicated right turn lane from I-20 westbound to the relocated Corley Mill Road.

Adaptive signal control devices (Smart Lights) are already in use along the US 378 corridor and provide improved efficiency; however, they are not a standalone solution to the existing and projected congestion.

There are no plans to increase the posted speed limits.

A Feasibility Study is currently in development for Andrew Corley Road (S-28/S-738) and Corley Mill Road (S-68) to analyze potential improvements. The project is being led by the Central Midlands Council of Governments (CMCOG) in collaboration with the South Carolina Department of Transportation (SCDOT), The Town of Lexington, and Lexington County. Mead & Hunt is also the engineering consultant for this Feasibility Study, so improvements proposed with the Sunset Split project will be seamlessly incorporated into the Feasibility Report. For additional project details visit:

https://centralmidlands.org/corley-mill-road-andrew-corley-road-feasibility-study.html

Widen US 378 to 8-lanes:

An alternative was considered which involved widening US 378 to eight (8) lanes along the existing alignment. This alternative required significant right-of-way impacts and would not fully address roadway capacity needs or improve wait times to acceptable thresholds, so it was eliminated from further consideration.

Build a Bypass (standalone):

The previously proposed Bypass was considered as a component to multiple alternatives in the 2022 Traffic Improvement Study. This Bypass was a two-lane roadway that began across from Corley Mill House, curved behind Woodridge Memorial Park, and tied into a new location intersection with Riverchase Way near Royal Oaks Lane. It then crossed I-20, and intersected US 378 at the current Davega Drive intersection. As a standalone project, the Bypass would not adequately address PM traffic, so it would not satisfy the Purpose and Need of the project.

Provide a New Interchange:

An interchange at Mineral Springs Road has been conceptually considered by other entities in the past; however, a new interchange would not address the Purpose and Need of this project.

Relocate Corley Mill Road without Sunset Split:

An alternative was considered which involved widening US 378 to six (6) lanes along the existing alignment and relocating Corley Mill Road behind the TD Bank Administration Building (M2). This alternative did not meet future roadway capacity needs for US 378 traffic or improve wait times to acceptable thresholds, so it was eliminated from further consideration. Additionally, the widening would require excessive impacts to surrounding businesses.

Relocate Corley Mill Road to the intersection of Northside Boulevard:

This alternative has been conceptually reviewed in the past, but resulted in significant residential and environmental impacts.

Relocate Riverchase Way to the intersection of US 378 and Ginny Lane:

Relocating Riverchase Way to the intersection of US 378 and Ginny Lane would require significant realignment which would impact the nearby cemetery (Woodridge Memorial Park and Funeral Home), Storage Sense – Lexington, and the Lexington County Fire Station 30.

Provide one continuously flowing “green” lane along US 378 eastbound and flyover for Corley Mill Road intersection:

The cost and impacts of elevating lanes for one continuously flowing “green” lane along US 378 eastbound and flyover for Corley Mill Road intersection would exceed the project budget due to the cost of right of way and the design and construction of bridges.

Redirect Ginny Lane traffic to Northside Boulevard and remove two lights on US 378:

Redirecting Ginny Lane traffic to Northside Boulevard is not feasible as there is a significant amount of traffic exiting Ginny Lane, particularly in the AM peak hours. Consolidating traffic to one intersection would result in worse traffic operations.

Extend Ginny Lane to connect with Mineral Springs Road:

Extending Ginny Lane to connect with Mineral Springs Road has been conceptually considered in the past; however, this would not address the Purpose and Need of this project and would need to be pursued as an independent project.

Tighten Sunset Split to tie back in east of Murphy Gas Station:

This idea was considered; however, it relocates the traffic congestion to Northside Boulevard. The Sunset Split project must extend through the Northside Boulevard intersection in order to meet acceptable traffic operations at that location.

Install a roundabout at US 378 and Corley Mill Road:

Roundabouts were investigated; however, the volume of traffic would not allow a roundabout to operate effectively. In addition, the property impacts would be excessive.

Other roadway improvements along US 378 at Target and beyond:

One roadway project cannot address all the traffic concerns along US 378 or in Lexington. Locations of areas identified for improvements are selected based on many factors such as congestion, delays and crash data.

Right of Way and Relocations

Residential and business relocations have been minimized to the greatest extent practicable. Right of way agents will be coordinating with any property owners who will be impacted by the project. Property owners who will be relocated will have access to relocation assistance to identify a new comparable property.

Commercial Property Impacts and Access

During the right-of-way process, coordination will occur between the property owner and right-of-way agents to determine the highest and best use of each property.

Coordination will occur directly with Sparrow Kennedy John Deere to assess the best options for ingress and egress for this property.

The proposed relocation of Corley Mill Road has been aligned to intersect with US 378 directly across from Honda of Columbia, which will improve their access.

Minimal right of way will be required from Northside Christian Academy and 7-Eleven Gas Station, and access will be maintained.

Modified access to CENTA Medical Group will be evaluated for conformity to Access and Roadside Management Standards (ARMS).

Vehicles turning left from US 378 westbound to Northside Boulevard currently utilize the middle two-way left turn lane (TWLTL) as storage during school pick up and drop off. With the Sunset Split project there will no longer be a TWLTL, so vehicles traveling US 378 westbound to Northside Boulevard will queue on Northside Extension, and if needed in the left turn lane off of US 378 westbound at the intersection with the Northside Extension. The lanes on Northside Boulevard are being retained in their existing configurations.

The Sunset Split project will not be adding traffic capacity/additional lanes within 500-feet of any residences along Riverchase Way or Royal Oaks Lane. Potential noise barriers along I-20 were analyzed by SCDOT during the development of the I-20 widening project and those that met feasibility and reasonableness factors at the time (under the previous noise policy) were constructed.

Regarding a noise barrier for residents of Mountain Laurel Court, the potential noise receptors would need to be separated into two segments – East and West of the newly realigned neighborhood entrance. There is only one (1) residence to the East, so a noise wall in this section would not be acoustically feasible, nor would it meet the cost effectiveness factor to be considered reasonable. Analyzing a noise wall to the West introduces another feasibility factor: Engineering Feasibility (Section 6.1). Due to topography along relocated Corley Mill Road, a wall adjacent to the new roadway would not be feasible from an engineering perspective. A noise wall directly along Mountain Laurel Court would significantly change the visual perspective for the residents, but it would be feasible to construct. There are four (4) residences to the West within 500-feet of relocated Corley Mill Road. One of these residences (128 Mountain Laurel Court) would not benefit from a noise barrier that starts west of the entrance, but the remaining three (3) residences could meet acoustic feasibility. Assuming a 700-foot-long by 15-foot-tall wall was considered, this would result in a 10,500 square foot structure. At 3,500 square feet per benefited receptor, a noise barrier at this location does not meet the cost-effective factor, thus it is not reasonable.

The project is being funded by the Town of Lexington through numerous funding sources: Tax Increment Financing (TIF), Hospitality Tax, and other appropriations from the State.

Funding Infrastructures

The Town of Lexington established an impact fee in February 2020 which requires the developers within the jurisdiction of the Town to contribute towards infrastructure upgrades associated with their development.

Penny Tax

The Sunset Split project is fully funded without a Penny Tax. A Lexington County Local Sales Tax has been proposed twice in the past 10 years and the voters were not in favor. The failure of the Sales Tax referendum is what led to the Town exploring other funding sources.

Planned zoning and development is considered with traffic forecasts; however, evaluation of zoning standards and decisions towards future develop is not within the scope of the Sunset Split project.