Frontage & Backage Roads
FrontageAndBackage.bmp
Access management and interconnectivity between properties is critical to maintaining a safe and efficient transportation system. To help accomplish both, the use of roadways parallel to an arterial can be used. A frontage road is normally located between the arterial and developed land. The disadvantage to a frontage road it the need to move the intersection of it and cross streets away from the arterial. This leads to inefficient use of space, higher costs and poor aesthetics. A better design is to use a backage road (aka reverse frontage road), one that runs behind developed land. Besides addressing the issues associated with a frontage road, it also allows for development on two sides of the road, thus increasing opportunity for economic development at a lower cost.
 
References
TRB Access Management Manual
NCHRP 348 (14) and NCHRP 420 (5) set forth the following guidelines for planning and designing frontage roads and service roads: (1) Frontage roads have been observed to function successfully when they serve low-density trip generation activities such as residential and small office areas; (2) Frontage roads for retrofit situations should operate one way and should enter and leave the main lanes as merging and diverging maneuvers...
Access Management Manual.pdfAccess Management Manual.pdf

FHWA Interstate Frontage Roads
FHWA frequently is asked whether interstate frontage roads are included in the Interstate System or the National Highway System(NHS). The general answer is "no." However, there are a number of cases where a partial exception to, or expansion of, or addition to this answer is appropriate.
FHWA Interstate Frontage Roads

Safe Access is Good for Business
FHWA: Safe Access is Good for Business

Texas Assessment
This paper seeks to provide a comprehensive evaluation of frontage road design policies by summarizing research results related to legal statutes affecting public access to roadways, discussing access policies and practices across the states, comparing land development and operations of corridors with and without frontage roads, summarizing studies on access-right valuation, and evaluating construction cost distinctions.
Texas Assessment