FYI For nonresidents of Concord, technically there are exactly three public parking spots, that is to say, spots for three cars at White's. These are reluctantly allowed to exsist so that the state will continue to stock the heck out of this pond [public access is required for state stocked waters].
Enforcement is sporatic but can arise without warning any time some fisherman annoys a local. Town cops ticket AND tow. Car top boats can launch and park at the boat ramp, I'm not sure if you need to be a resident.