"Adopt-a-Highway" is a name for a type of program, popular in
America, whereby a business, nonprofit organization, or other entity pledges to clear the
roadside of a designated stretch of public
highway of
litter or other debris, and in return the government posts signs nearby acknowledging the group's work. The first such program started in 1985, when a stretch of
US Highway 69 running through
Tyler, Texas was adopted by the Tyler
Civitan Club, and similar programs are now in operation in all 50 U.S. states and
Puerto Rico.
As there is no single central authority operating such programs, they vary in specifics from area to area, but generally the state Department of Transportation or other supervising entity provides trash bags to be filled and left along the side of the road for later collection, with some programs also supplying orange safety vests to increase participants' visibility. For their part, participating groups provide manpower, a sort of volunteer corvee, usually pledging to clean the highway at least twice a year.
Acknowledgment signs are typically but by no means exclusively blue with white text, as with many other informational signs. Many of the signs I have seen throughout the northeast consist of two panels mounted one atop the other, with the upper announcing the program and the lower either naming the participant or noting that the region is available for "adoption", thus allowing for easier replacement as groups enter and leave the program.
In accordance with national regulations specifying that no advertisements* are to be erected on the rights-of-way of any highway paid for in full or in part with federal monies (which, of course, is all of them), the U.S. Department of Transportation attempted in 2001 to mandate that recognition of participants in such programs should be limited to an acknowledgement of their name in standard fonts and text size, prohibiting logos or other advertisement elements. In the face of objections from states worried about losing a valuable incentive for participation, the federal DoT backed down, and its current stance is that logos may be allowable but slogans or instructions for contact (directions, phone numbers, or internet addresses) are not.
The ambiguous semiprivate, semigovernment nature of adopt-a-highway programs and signage was also the basis for a noteworthy First Amendment case when in the 1990s a Missouri branch of the Ku Klux Klan sought to adopt a highway. After some delaying, Missouri rejected the Klan's application on the nominal basis that they were, among other things, ineligible for the program under laws prohibiting the use of federal highway monies for supporting groups engaged in racially discriminatory practices.
The Klan brought suit, and the case wound its way through the courts, with the 8th Circuit Court of Appeals eventually ruling in their favor, saying that Missouri was clearly engaged in discrimination on the basis of the Klan's constitutionally protected views. Missouri further appealed the course to the Supreme Court, but the court denied certiorari and let the ruling stand.
While this technically does not represent an affirmation of the lower court's decision and limits the ruling's precedential application to the 8th Circuit, it is widely believed, on the basis of recent rulings in such cases as Boy Scouts of America v. Dale and on older precedents on viewpoint discrimination in the awarding of government benefits, that if the Court had accepted the case it would have upheld the Klan's vindication. For those interested in such things, this case was Cuffley v. Mickes, 208 F.3d 702 (8th Cir. 2000), cert. denied sub nom., Yarnell v. Cuffley, 532 U.S. 903 (2001).
*Motorist Service Signs, those blue signs employing logos to direct drivers to restaurants, motels, gas stations, or other motorist-oriented service providers, are specifically allowed by the relevant regulations.