memo-12-08-2015-14

MEMO TO:           Mayor Barber and Board of Commissioners

FROM:                  Frank A. Rush, Jr., Town Manager

SUBJECT:           Presentation – Potential Installation of Traffic Roundabouts to Improve NC 58 Traffic Flow

I have scheduled time on the Board’s December 8 meeting agenda to receive a presentation about potential traffic improvements along NC 58 in Emerald Isle that are intended to improve traffic flow at the Town’s 4 signalized intersections.  The purpose of the presentation is to educate the Board and the community about the potential improvements, and receive feedback from the Board and the community so that additional planning may occur in the coming months.

The potential improvements are being considered as part of the NC 58 Corridor Study that has been underway (led by the Down East Regional Planning Organization) for the past several months.  The scope of that study includes the entire NC 58 corridor from the NC 24/58 intersection along all of Bogue Banks over the Atlantic Beach bridge and up to the US 70 intersection in Morehead City, with a goal to improve traffic flow during peak traffic periods.

Patrick Flanagan, lead planner for the Down East Regional Planning Organization, will brief the Board on the potential improvements, and will likely be accompanied by representatives from the NC Department of Transportation.

Potential Installation of Traffic Roundabouts

The most significant preliminary recommendation in the NC 58 Corridor Study is the installation of traffic roundabouts at the 4 signalized intersections in Emerald Isle:

  • NC 58 / Coast Guard Road

200 ft. wide right of way available

Full, single-lane roundabout contemplated

  • NC 58 / Loon Drive (Emerald Plantation Shopping Center)

200 ft. wide right of way available

Mini-roundabout contemplated, but full, single-lane roundabout preferred

  • NC 58 / Mangrove Drive (K&V Plaza, CVS Pharmacy)

200 ft. wide right of way available

Mini-roundabout contemplated, but full, single-lane roundabout preferred

  • NC 58 / Bogue Inlet Drive

100 ft. wide right of way available

Mini-roundabout contemplated.

A roundabout is an intersection feature that eliminates the need for traffic signals and keeps traffic flowing continuously by requiring entering traffic to yield the right of way to traffic already in the roundabout.  Traffic flows in a single direction around the feature, with only right turns out of the roundabout in the desired direction.  There are several different sizes of roundabouts:  large traffic circles, double-lane roundabouts, single-lane roundabouts (contemplated for Emerald Isle), and compact / mini-roundabouts (contemplated for Emerald Isle).

I have included photos of single-lane roundabouts currently installed in Ocean Isle Beach, NC and Asheville, NC to provide a better understanding of a traffic roundabout, along with a diagram of a mini-roundabout.  I have also included a NCDOT brochure about roundabouts, along with a 2011 study of traffic safety at roundabouts in North Carolina.

NCDOT staff has reviewed traffic counts and crash data for the 4 intersections in Emerald Isle, and believe that the installation of traffic roundabouts in Emerald Isle will improve traffic flow during peak periods, and will reduce the potential for backups and delays.  Initial discussion with Patrick Flanagan indicated a preliminary NCDOT recommendation for a full, single-lane roundabout at the Coast Guard Road intersection and three mini-roundabouts at Loon Drive, Mangrove Drive, and Bogue Inlet Drive.  Because there is sufficient right of way to accommodate full, single-lane roundabouts at Loon Drive and Mangrove Drive (200 ft. right of way available), in the interest of consistency, and for aesthetic reasons I requested that the final NC 58 Corridor Study consider including full, single-lane roundabouts at Loon Drive and Mangrove Drive rather than mini-roundabouts.  There is not sufficient right of way for a full, single-lane roundabout at Bogue Inlet Drive (only 100 ft. right of way available).  A full, single-lane roundabout requires between 100 ft. and 150 ft. of diameter.

The Town’s existing bicycle path and sidewalks would be integrated into the new roundabouts, slightly set back from the roundabout feature and also including an island midway across the road.

Other Potential Traffic Improvements

Other potential improvements under consideration include longer, additional, and/or realigned turn lanes at the Town’s signalized intersections.  It is likely, regardless of whether or not a traffic roundabout is installed, that a separate right-turn lane (slightly away from the main intersection) will be planned for the Coast Guard Road intersection for traffic entering Emerald Isle (utilizing the available right of way between NC 58 and Bell Cove Village shopping center).  This separate turn lane would enable traffic headed down Coast Guard Road to avoid the intersection altogether.

If the roundabouts are not installed, it is possible that other turn lane improvements could be constructed at each intersection to enable those vehicles to exit NC 58 more efficiently, thereby enhancing traffic flow on NC 58.

Potential NC 58 / Coast Guard Road Roundabout

The installation of a roundabout at the NC 58 / Coast Guard Road intersection is likely the single greatest traffic flow improvement being considered, as that intersection is viewed as the main choke point during peak traffic periods.  The installation of a roundabout at this intersection also represents a significant opportunity to improve aesthetics at this area.  I envision a new “Welcome to Emerald Isle” sign being installed in the center of the roundabout, along with attractive landscaping improvements.

It will be important for NCDOT staff to fully consider and evaluate the relationship with the Coast Guard Road / Reed Drive intersection when planning any new roundabout at the NC 58 / Coast Guard Road intersection.  As you know, recreational vehicles often use that intersection to access the Holiday TravLPark, and appropriate planning should occur for these vehicles.  Additionally, Reed Drive represents the only alternative to access the Coast Guard Road communities, and is a popular alternative route.

Additional Curb & Gutter Improvements in the “Downtown” Area

As part of any traffic improvements near the Bogue Inlet Drive intersection (either including a mini-roundabout or not), I have asked Patrick Flanagan to also include curb and gutter improvements on both sides of NC 58 between the new Welcome Center and the US Post Office.  As you know, this area now includes older, somewhat uneven curb and gutter “islands” near commercial driveways, and it would be helpful to remove these features and reconstruct more modern and aesthetically pleasing curb and gutter features in the “downtown” area.  It may also be possible to consolidate some existing commercial driveways (for locations that have more than one driveway) to improve traffic flow and aesthetics.

I have attached an aerial photo map indicating the area to be considered for additional curb and gutter improvements.  The total distance is approximately 875 feet on the north side of NC 58, and approximately 700 linear feet on the south side of NC 58.  I believe this improvement, potentially also including limited on-street parking spaces, could be a significant aesthetic improvement and further the Town’s goal to create more of a “downtown” feel in this area of Emerald Isle.

Process and Timeline

If the Board and the community are interested in pursuing the roundabout improvements, the proposed project(s) could be incorporated into NCDOT’s planning process in 2016.  Depending on how the project(s) scores, it is possible that funding could be made available within the next 2 years, although it is probably more likely that any such improvements would be programmed further out.

Because the cost of these improvements is relatively small (compared to many NCDOT improvement projects), it is possible that these improvements could be “bumped up” on the schedule if other projects are delayed or have unanticipated savings.  Thus, I am optimistic that if the Town pursues these improvements that they could be constructed sooner rather than later.  The estimated construction cost for each full, single-lane roundabout location is likely in the $250,000 - $500,000 range.

Steel Traffic Signal Pole Funding Request

The Town previously requested funding from the NC General Assembly and the NC Board of Transportation (a total of $684,000, to be matched with $36,000 from the Town) for the installation of new steel traffic signal poles at the Town’s 4 signalized intersections.  The Town has been working with NC Representative Pat McElraft and NC Senator Norm Sanderson to secure funding from the NC General Assembly, and with NC Board of Transportation member Gus Tulloss to secure funding from NCDOT.  These efforts continue, and I remain optimistic that the Town will ultimately secure this funding at some point in the future.

Obviously, if the Town pursues the installation of roundabouts, there will be no need for new traffic signal poles.  Because of uncertainty regarding the timeline for the funding and installation of roundabouts, I recommend that the Town continue to pursue State funding for the new steel traffic signal poles until such time that the funding for the installation of roundabouts is confirmed.  If and when funding is secured for the steel traffic signal poles, it may also be possible to “convert” this funding and use it for the roundabout installations.  Obviously, if the Board is not interested in pursuing the roundabouts, the Town would continue to seek State funding for the new steel traffic signal poles only.

Community Aesthetics

Assuming that NCDOT’s traffic engineers are correct that roundabouts will improve traffic flow and safety along NC 58 in Emerald Isle, I believe this represents a significant opportunity for the Town to improve the overall aesthetics of our community.  The installation of the roundabouts provides an opportunity for new infrastructure, a new look, removal of unsightly traffic signal poles and cables, landscaping enhancements, and new curb and gutter improvements.  The continued aesthetic improvement of Emerald Isle has been among the Town’s highest priorities over the past decade+, and the proposed roundabouts could further that goal.

I look forward to receiving Patrick Flanagan’s presentation at the December 8 meeting, and await the Board’s and the community’s feedback.