DESMAN
percentile, and drivers are practiced at parallel parking, it possible that up to seven cars might be parked
in the same 100’. Inversely, four large vehicles parked carelessly with several feet of separation between
each could fill the same 100’ block face, even though there is enough linear distance to support five
spaces.
Any interruption in the curb will further reduce the practical parking capacity of a length of roadway. Using
the example of the 100’ curb face, if there is a driveway of 10’ in width in the middle of the block, that
would reduce the 100’ of uninterrupted space into two segments of 45’ in length each, reducing the
practical capacity to just four vehicles at an assumed set aside of 20’ per space. The addition of second
driveway on the same block could easily reduce practical capacity to just three vehicles, even if it is only
10’ in width, because it would further reduce the total number of uninterrupted 20’ lengths of open curb
space along the block face.
Other factors which impact the amount of uninterrupted, contiguous space along a curb face include
minimum setbacks from various structures. Some of these setbacks are prescribed to preserve the
efficient flow of traffic within the community, including emergency and service vehicles. As a general rule,
most communities mandate no vehicle may park within a certain distance of an intersections to
accommodate the wider turning movements of long wheelbase vehicles such as fire engines, ambulances,
snow plows, and garbage trucks. Other setbacks, such as prescribed ‘no parking’ areas adjacent to fire
hydrants, exist to assure quick and easy access to resources during emergencies.
Other setbacks such as required ‘no parking’ areas to either side of a curb cut for a driveway or alley exist
to preserve site lines for drivers so they can see oncoming traffic along the roadway from a safe vantage
point within the driveway or alleyway. Without these setbacks, individuals could park right up to the edge
of the curb cut, requiring drivers attempting exit the driveway or alleyway to pull into the roadway to see
if oncoming traffic is present before pulling out.
DESMAN reviewed the code of ordinances and zoning code for Nashua as well as the ten comparable
communities for required setbacks from crosswalks; stop signs or traffic signals; driveways; alleyways;
intersections without crosswalks, stop signs, or traffic signals; fire hydrants; and other structures.
DESMAN also collected information, where available, on dimension standard for parallel parking space,
travel lanes in roadways, and other pertinent regulations pertaining to parking on public streets. Where
there were no clear regulations regarding these items, DESMAN noted this category as “n/a”. A summary
of this research is shown in Table 3.
Table 3: Dimensional Standards for On-Street Parking
City: Nashua Albany Ann Arbor Concord Concord Manchester Meridian Portland Portsmouth Rochester West Harttord
State: NH ay Mi NC NH NH 8) ME NH MN ct
Setback from Crosswalk nfa 20° 20° 20 20° aw 2° 20 nja 20" 25°
Setback from Sign/Signal 2s 39 30 50° a0 30, x” x nfa cy nfa
Setback from Oriveway z ‘ nfa 4 nfa s 5 nfa a nja 3 nfa
Setback from Alley nfa nja 4 nfja nfa * nfa ‘ aja nfa nfa 5 nfa
Setback from Intersection r 2s * nfa Ly aga 2 2 ‘ nfa 25° 20° 2 re
Setback from Fire Hydrant 15° 1s iy is' iy y bh 19° ka 1 17
Setback from Other Various * 20-75 *o2o-7s' 7 zot7s) * az ae sae! * fa 2-75 ona
Parking Stall Dimensions 9x23" ex2s * otxz0 * gste23 * otx22 * axons? * otxax * on 22 sx2 * B7SK20 || KD
Orive Aisle Width afa woo oar Soa Fa aayzot Yo azyast * azyze yz 10y2t 12/20
Other Regulations nf ix onda wz onfa nfa aja ofa * nia ze3a' n/a
As the table shows, there are currently regulations in Nashua dictating setbacks from signs and signals,
driveways, intersections, and fire hydrants. Article XIl of the Nashua Cade of Ordinances also carries
multiple sections (320-61, 320-62, 320-64, 320-69, 320-70) which dictate where parking may or may not
