Hi Christine, we at Winding River can relate to your situation. Winding River has over 1000 acres, our gated neighborhoods have a combination of 14 miles of community-maintained roads; however, our development is cut in half by Zion Hill Road which is state owned 2-lane road.
Within the gates, we have studied this issue for several years, trying to determine who are the speeders- residents or all the subcontractors as we have added 30-40 houses a year for the past four years. Our inside the gate speed limit is 25. Zion Hill has a posted speed limit of 35 mph through the Winding River boundaries and 45 passed our boundary.
Last year we rented several speed tracking and recording devices and tracked the detailed information they provided such as number of vehicles, their speed and time of day. The committee moved these devices around the neighborhoods. At year end we had a lot of data. Most vehicles stayed within 3 MPH of the speed limit. Our roads are curved throughout the development. The few longer stretches of straight roads showed higher speeds. These devices provided a visual instant awareness reminder. We ruled out speed humps as an option, they are not usually endorsed by emergency responders and are costly to maintain and would be a nuisance to the majority of the abiding residents. Rather, we bought several advanced speed tracking devices that had enhanced features such as a camera which can record a vehicle when set to an excessive speed limit.
Zion Hill, which like you, is a cut through to new developments and we have an elementary school at one end, and Carolina National Golf Club in the middle of our development, is another story. Several years ago, Zion Hill was 45 MPH. we made multiple requests to the DOT to conduct a speed and traffic analysis. They complied and as a result, lowered the speed limit to 35 MPH on Zion Hill beginning at the intersection of HYW 211, passing in front of the school and proceeding through Winding River, where it then jumps to 45MPH immediately passed our boundary. But with scare resources for enforcement, it can be dangerous. Therefore, our residents are strongly encouraged to drive the speed limit whenever they are on Zion Hill. Doing so frequently results in flashing lights, bumper riders and finger waving, but it makes a difference. Several of our neighborhood entrances are on blind curves and recovery time for speedsters is severely diminished. Reach out with any questions. Please share any success stories. Robin Edwardsen

Devaun Park has installed speed bumps in areas of concern. All of our streets are private so we have some leeway in that regard.

St. James Plantation's streets are private. We have 71 miles of roads with most streets within the various neighborhoods having a posted speed of 20 mph. There are a few roads that are longer with a posted speed limit of 30 mph. Not all streets within the community have sidewalks; therefore, residents have to walk on the roads along with vehicles and bicyclists. Many of our roads are narrow, so there has been an obvious safety concern and effort to control speeding. We have several radar speed signs located throughout the community. They capture speed data and vehicle counts and have a positive effect of slowing vehicles down. We also have a security contractor with 3 vehicles patrolling the entire community 24/7. Speeders receive citations for a "rules" violation for speeding. We also have a speed radar camera and can issue citations for excessive speeding. The camera can be placed anywhere in the community. We a safety and security committee of residents concerned about safety issues. They have emphasized the need to share roads and exhibit safe behavior. There are best practices for pedestrians and bikers. Community education on these topics is continuous.

We installed two speed humps on one very narrow and busy 20 mph street. If driving the speed limit, there is no problem. Residents were up in arms when this decided, but after installation, there have been no complaints. There is a type of speed hump that be installed to allow emergency vehicles like fire trucks and ambulances passage without jarring, called speed cushions that have a wide gap to accommodate the wider wheelbase of those vehicles without slowing down.