A few more rounds on the roundabout

Kicking off his presentation on the proposed roundabout for the intersection of Seven Farms Drive and Daniel Island Drive at the Daniel Island Neighborhood Association meeting on Tuesday, February 2, Berkeley County Councilman Josh Whitley mused that in the 11 months he has served in that role, he has spoken at the DINA podium about the traffic juncture three times, and on all three occasions the controversial configuration was different. “I can tell you that is based in large measure on the feedback from this organization,” he asserted. “Historically, and currently, every time we come here we get great feedback.”

One of the earliest intersections on Daniel Island, the one at Seven Farms and Daniel Island Drives has become congested and, in the opinion of many, dangerous, particularly during the morning school and work rush and the afternoon school dismissals. Though the intersection is maintained by the City of Charleston, it did not appear to be of high priority among the others needing attention in that jurisdiction. As a result, Berkeley County got involved several years ago, agreeing to make the enhancement of the intersection a penny tax project.

The initial plan was to add one turn lane at a $150,000-$200,000 price tag, but when that estimate crept up to $400,000, the idea to alter the configuration from all four directions became more appealing. The cost of that was estimated at $750,000, and the renderings were presented to DINA at the September 8, 2015 meeting.

“But the question still, was, ‘why not a roundabout?’” Whitley maintained. “I didn’t know the answer; I started asking the question. And the answer was cost.” But since the comparison was no longer to the first price tag of $150,000, Whitley said he approached Daniel Island Company President Matt Sloan and Daniel Island Property Owners Association Vice President for Community Services Jane Baker to gauge their consideration of a roundabout. “Not only had they evaluated it,” Whitley recalled, “they’d gotten preliminary engineering drawings, and they had brought it to DINA three or so years ago to great reception.”

For Whitley, there were two primary questions to consider: is it a good traffic flow solution, and is it safer for pedestrians and cyclists? “This happened almost overnight… about 48 hours… to get it into a quarter of a million dollar plan,” the councilman conveyed. “That’s why it appeared to come as a surprise. The opportunity for funding was pretty much a one-shot deal. I’m very pleased that we’ve been able to secure $2.6 million for this roundabout. I don’t think it will cost that – I think it will be closer to $1 million – but we needed to secure the funds first.”

Tony Woody, longtime Daniel Island engineer with Thomas and Hutton, brought conceptual renderings of the proposed roundabout. He also came armed with some statistics surrounding intersection design.

In terms of efficiency, Woody stated that engineers design intersections for “worst case scenario,” which typically means the busiest two hours in the morning and the busiest two hours in the late afternoon/early evening. Under those conditions, a roundabout operates on par with a signaled light. However, the rest of the day when traffic volume is lighter, Woody says that research shows a higher volume of traffic is able to move more smoothly – yet more slowly – through a roundabout than through a timed-light intersection.

Speaking on safety, Woody explained that the ability for roundabouts to reduce speed is the biggest benefit, and the potential “conflict” with pedestrians is significantly lowered. “For a standard, signalized intersection, there are about 24 points of conflict,” he shared. “With a roundabout, there are eight.” The Federal Highway Administration has published data that indicates 90% fewer fatalities, 76% fewer injuries, and 35% fewer crashes in roundabouts versus signaled intersections.

Lastly, Woody suggested that roundabouts serve an intangible benefit in that traditionally across the nation, these traffic circles have denoted the center of town and created a “sense of place, a special area.” After fielding a couple questions from the crowd regarding pedestrian safety through the roundabout’s designated crosswalks, Whitley gave notice of turning the microphone to the night’s final guest speaker. And that’s when things started to heat up.

“Josh, that’s not fair,” interjected one member.

“You guys come in and, all of a sudden, you’ve reinvented history, and said ‘a ton of people want a roundabout.’ You don’t have records of it, it was a total surprise to DINA, and who’s driving this? And the question about the crosswalk is the most important question you’ve got out here. There are no gaps at 7:30 in the morning, and there are no gaps at 3:30 in the afternoon.”

Various concerns - from seniors travelling through the intersection on foot or motorized scooters to parents with young children crossing to Daniel Island Academy to high schoolers walking or biking to the business district for lunch – were then raised without further invitation. “You’re asking children to make that determination of when to cross, rather than a light or signal,” observed one DINA member. “That terrifies me.”

Even the issue of parking spaces lost to the roundabout reconfiguration was brought forth.

Whitley acknowledged that a roundabout would necessitate some accompanied coaching for kids by parents, re-familiarity with rules of the circles by all drivers, and tighter enforcement of right-of-way and yielding at crosswalks. But he stood firm that, in his opinion, the roundabout was a solution superior to that of previous iterations.

Woody also restated that a vehicle must slow down to enter a roundabout, versus the freedom to race through a signaled intersection, and that yield signs would be stationed at each approach to the circle. He added that there are options for safety enhancements as well, such as light-up crosswalks and pedestrian signals, which can be incorporated into the roundabout.

In the end, Williman asked that the crowd recognize this is a very tentative and variable design, and that the concept is in its initial stage. He welcomed feedback and comments and assured that the best resolution for Daniel Island would be determined.

For complete coverage of the rest of the DINA meeting, see the story beginning on page 12.

The next DINA meeting will take place at Church of the Holy Cross on Tuesday, April 5, and Mary Gould will return to speak about the progress of the Daniel Island Performing Arts Center project.