17-4-10 Mixed-use streets

The requirements of this section, rather than the town's subdivision street standards manual, apply within the BU, DN, and DT zones.

A.   Centerlines of offset thoroughfares entering onto a collector or arterial must be at least 300 feet apart.

B.   Streets must connect to other streets, forming a network. The planning manager is authorized to permit a deviation to this requirement, thereby allowing a dead-end street terminating in a cul-de-sac, consistent with the following requirements:

   1.   The planning manager, in consultation with the town engineer, makes one or more of the following determinations:

      a.   The physical terrain will make connection to other streets cost-prohibitive or unsafe.

      b.   Existing development physically blocks connection to other streets.

      c.   Access restrictions or standard traffic engineering considerations make connection impossible or unsafe.

   2.   Connectivity for bicycles and pedestrians should be created and maintained whenever possible, even when there is no vehicular connectivity.

   3.   No cul-de-sac may exceed the greater of 300 feet to the center of the bulb or one-half block in length.

C.   Block standards.

   1.   Blocks consist of lots surrounded by streets.

      a.   Lengths of block faces may not exceed the maximum length of a block face, measured along lot lines, per table 13, except the planning manager may increase the maximum length by up to 10% to accommodate specific site conditions.

 

Table 13. Maximum block face length
Zone or Intensity	Length in feet
BU low intensity	500
BU medium intensity	400
BU high intensity	300
DT	300
DN	400

 

      b.   Where two or more zones or intensities occur on the same block face, the block face length may not exceed the shortest required length.

   2.   The planning manager may exempt blocks adjacent to undeveloped land, areas unsuitable for development, or pre-existing incomplete blocks from a limitation on block length.

   3.   Block faces exceeding 500 feet must be subdivided with a sidewalk extending through the block that is 12 feet wide, minimum.

   4.   Rear alleys are required for medium and high intensity areas in the BU zone and in DT and DN zones. Rear alleys are not mandatory where the rear lot lines are at the edge of the site to be subdivided or where the block has been previously subdivided.

D.   Intersection sight visibility distances are determined based on the subdivision street standards, except that sight visibility zones are not required for mixed-use zone intersections controlled by a traffic signal or stop sign.

E.   Streets in mixed-use zones must be designed as follows:

   1.   Streets classified as arterials shall use the avenue street cross section (table 14, cross section 1)

   2.   Streets classified as collectors shall use the avenue or street cross section (table 14, cross section 1, 2, 3, or 4).

   3.   Streets classified as local roadways shall use the street cross section (table 14, cross section 2, 3, or 4).

   4.   As an alternative to the above, streets in the BU high intensity area and in the DT zone may use the commercial street-mixed parking or parking plaza street cross sections (table 14, cross section 7 or 8).

   5.   The alley cross section (table 14, cross section 5) may be used for secondary, service, or parking access.

Table 14. Mixed-use street cross connections
1. Avenue
Street type	Avenue
Right-of-way width	100 feet
Pavement width	62 feet total (31 feet each)
Movement	Free movement, inner lanes
Travel lanes	Four
Parking lanes	Parallel both sides, eight feet
Curb radius, effective	Ten feet
Walkway type	Sidewalk, ten feet
Planter type	Four-foot by seven-foot tree well
Curb type	Vertical, with gutter
Street trees	Maximum 30 feet on center
2. Commercial street with diagonal parking
Street type	Commercial street with diagonal parking
Right-of-way width	80 feet
Pavement width	57 feet
Movement	Free movement
Travel lanes	Two
Parking lanes	Diagonal both sides, 17.5 feet
Curb radius, effective	Ten feet
Walkway type	Sidewalk, 11.5 feet
Planter type	Four-foot by seven-foot tree well
Curb type	Curb with gutter and/or ribbon gutter
Street trees	Maximum 30 feet on center
3. Commercial local street with parallel parking
Street type	Commercial local street with parallel parking
Right-of-way width	36 feet; utility and access easement in the sidewalks
Pavement width	36 feet
Movement	Free
Travel lanes	Two
Parking lanes	Parallel both sides, eight feet
Curb radius, effective	Ten feet
Walkway type	Sidewalk, 12 feet
Planter type	Four-foot by seven-foot tree well
Curb type	Vertical, with gutter
Street trees	Maximum 30 feet on center
4. Street
Street type	Street
Right-of-way width	32 feet; utility and access easement in curb ways
Pavement width	32 feet
Movement	Slow
Travel lanes	Two
Parking lanes	Parallel both sides, six feet. Omit mid-block for 40 foot long staging area
Curb radius, effective	Ten feet
Walkway type	Sidewalk, five feet
Planter type	Curbway, eight feet landscaped
Curb type	Mountable, with gutter
Street trees	Maximum 40 feet on center
5. Commercial alley
Street type	Commercial alley
Right-of-way width	22 feet
Pavement width	11 feet
Movement	Slow
Travel lanes	Two
Parking lanes	None
Curb radius	Four feet chamfer
Walkway type	Not applicable
Planter type	Not applicable
Curb type	Not applicable
Landscape	Not applicable
6. Residential alley
Street type	Residential alley
Right-of-way width	22 feet
Pavement width	12 feet
Movement	Yield
Travel lanes	One
Parking lanes	None
Curb radius	Four feet
Walkway type	Not applicable
Planter type	Not applicable
Curb type	Not applicable
Landscape	Not applicable
7. Commercial street - mixed parking
Street type	Commercial street - mixed parking
Right-of-way width	90 feet
Pavement width	48 feet
Movement	Free
Travel lanes	Two
Parking lanes	Diagonal, 18 feet; parallel, 8 feet
Curb radius, effective	Ten feet; 25 feet at existing intersections
Walkway type	Sidewalk, 21 feet
Planter type	Tree well, varies
Curb type	Vertical, with gutter
Street trees	Maximum 40 feet on center
8. Parking plaza street
Street type	Parking plaza street
Right-of-way width	107 feet
Pavement width	74 feet pervious pavers
Movement	Free
Travel lanes	Two
Parking lanes	Diagonal, 18 feet center; parallel, eight feet sides
Curb radius, effective	Ten feet; 25 feet at existing intersections
Walkway type	Sidewalk, 15 feet
Planter type	4 ft. x 4 ft. tree well, 6 ft. x 9 ft. center wells
Curb type	Vertical
Street trees	Maximum 40 feet on center