In New Hampshire, we prioritize transportation spending through the Ten Year Transportation Improvement Plan.  Our Department of Transportation (NHDOT) helpfully provides a brochure to explain this two year process.  You will see that the first step on this flow chart is for the regional planning commissions (RPCs) to assess local and regional transportation needs in the fall of even years (such as 2014), solicit new projects from communities, then evaluate them, rank them, and pass on their recommendations to NHDOT by May 1^st the following spring.  NHDOT then prepares a draft Ten Year Plan based on these recommendations and submits it to the Governor’s Advisory Commission on Intermodal Transportation (GACIT).  GACIT sends it to the Governor, who then sends it to the Legislature.  The 2015-2024 plan was signed into Law by Governor Hassan August 1, 2014.  The process then starts all over again.
The GACIT is comprised of the five Executive Councilors, plus the Commissioner of NHDOT in a non-voting role, as defined by RSA 228:100.  They hold public meetings around the state on the Ten Year Plan in the fall of the odd years (such as 2015).  You can find a summary of the 2013 hearings, plus a copy of the transmittal letter from GACIT to the Governor, on this webpage.

The question is, how do projects get into this process in the first place?  The answer is that the RPCs solicit projects from the municipalities and other institutions (universities, transit agencies) in their regions, usually through the local planning boards.  The RPCs start this as early as October. Projects originate here as well as through regional corridor studies guided by steering committees of local representatives, or statewide needs identified by NHDOT. Some specific federal funding programs targeting bicycle and pedestrian projects, such as Transportation Alternatives or Recreational Trails, have separate  application windows that run on different cycles, but bicycle and pedestrian projects are also eligible for the general Ten Year Plan solicitation process.

If your community would benefit from having a project included in the Ten Year Transportation Improvement Plan, start now by talking to your planning board and reaching out to your regional planning commission.  Ask your planning board how they decide which projects to submit to the RPC.  It all starts locally.