How do I access my site?
When making a site selection for your new development there are many considerations that need to be made. One that is a big factor but isn't always at the top of everyone's list is the ability to access the site and what type of access is possible.
Access to the site will generally be controlled by whatever entity owns the road right-of-way that the site attaches to and that entity will have guidelines and regulations to address what type of access is allowable. This is commonly the state department of transportation or local municipality.
Some of the typical parameters that are controlled and assessed are:
Sight Distance - clear line of sight in both directions based on specific eye heights
Driveway Spacing - distance available between existing roads & driveways
Driveway Grade - the slope of the proposed driveway
Driveway Width & Radii - geometric minimum requirements based on type of traffic
Driveway Throat Length - distance available to first potential conflict point
Corner Clearance - spacing so that driveway radius does not cross property lines
Each of these parameters must be considered before the proposed access can be permitted. The specifics of each of these requirements can be found within the governing agency's regulations. For example, in South Carolina, the Department of Transportation has a published Access & Roadside Management Standards (ARMS) Manual which you can find here. Always be sure that you are using the latest updated version of any regulation and confirm if there have been published updates.
Sight distance is one of the most critical items to address regarding your site selection. If the site is located near a curve or a high point in the roadway these are indicators that there may be a sight distance issue. The best way to check the sight distance is to physically go out to the sight with another person and tape measure to confirm the distances that you can maintain sight of each other - but there are specifics about the eye height you have to measure from and the distance from the roadway into your site that you need to make sure you have right as well.
So what happens if you can't meet some of the requirements for access in your area on your site?
Short of finding a new site, there are a couple of potential options:
Shift access to a less preferable location that meets requirements (if available)
If you can't meet the requirements in your current location you could try shifting the access location on your site which might not be your preference, but may meet the requirements.
Alternatively, you opt for a restricted access like a right-in right-out or other controlled access driveway condition. These options are usually not the preference as they by nature restrict access to your site from one or more directions, but they may be the only option for some sites where there are limited access options.
In some rare cases, you may be able to apply for a waiver for your access if it does not create a safety issue and an engineer will sign off on it for you. This would be a last resort and ultimately the governing agency has the final say on whether or not to grant a waiver.
Site access is a critical part of the site selection process and has more considerations involved than many people might think. Make site access one of your first considerations for your site selection because if people can't get into your site there is no reason to build there!