§ 29. Streets and alleys.

29-1

Plans.

A.

Typical sections showing the proposed pavement width, type, thickness and crown; the proposed curb or curb and gutter type as required, location in relation to centerline and exposure; the proposed sidewalk dimensions and location in relation to curbs and property lines; the proposed street grading slopes, for each of the different types of streets and alleys in the subdivision.

B.

Alignment of each street, alley, sidewalk and crosswalkway showing a beginning and ending station; each deflection angle of the centerline and the station of the point of intersection; the station of the point of curvature and the point of tangency of each curve; the station and angle of intersection of each intersection with another street, alley or drainage easement; the station and radius of each curb return; the location of adjacent right-of-way lines; the location and limits of sidewalks and curbs of each street; the location of monuments.

C.

Location, description, and elevation of benchmarks; the top of curb grade at each curb end, each fifty-foot station and each end of each curb return; the centerline grade at each end and at each fifty-foot station of alleys; the gradient of each tangent grade and the location and length of each vertical curve; the direction of storm drainage flow at each intersection; the profiles of streets, alleys, and drainage ditches shall show the natural ground at adjacent property lines and the proposed centerline.

D.

Scale, north arrow and date. Plan and profile shall be drawn to scale of one (1) inch equals fifty (50) feet horizontally, and one (1) inch equals five (5) feet vertically.

E.

All street and alley plans and profiles shall bear the seal of a registered professional engineer.

29-2

Design standards.

A.

At each street intersection, the curb shall be rounded with a curve of radius "R," varying with the interior angle as specified in Table 1 (not required in rural subdivisions).

B.

At each intersection, the property lines at each block corner shall be rounded with a curve or[of] radius "R," varying with the interior angle as specified in Table 1.

C.

Street and alley grades shall, in general, conform to the terrain, and shall not exceed the grades specified in Table 2. No street or alley grade shall be less than three-tenths of one (1) percent, unless otherwise specified by the city engineer.

D.

Horizontal curve radii shall not be less than those specified in Table 2.

29-3

Construction requirements. The subdivider shall excavate, fill and grade all alleys and new streets, including sidewalk areas where required within the subdivision, so that pavements and sidewalks may be constructed along lines and grades approved by the city engineer. In general, the grades of sidewalk areas shall be so established that no extreme or abrupt changes in grade are encountered within blocks, but variations may be allowed where because of soil conditions, topography, or valuable trees, the establishment of such grades would result in undue hardship. New streets and alleys shall be surfaced in accordance with plans and specifications approved by the city engineer and constructed under his supervision. No street shall be surfaced until the underground utilities which are to be installed in the portions of the streets intended for vehicular traffic have been installed.

New streets (including previously dedicated rights-of-way) and existing unpaved streets abutting both sides to a new subdivision or resubdivision shall be constructed in accordance with the standards set forth in this exhibit and the following requirements:

A.

Subgrade preparation: Subgrade shall be prepared in accordance with the specifications of the City of Carrizo Springs and compacted to a Proctor dry density of not less than ninety (90) percent. When fill is required it shall be placed in uniform lifts not to exceed six (6) inches in depth prior to compaction with pneumatic rollers or eight (8) inches prior to compaction with other types of rollers. Each lift shall be compacted to ninety (90) percent Proctor density before succeeding lifts are placed.

B.

Flexible base: When asphaltic pavement surfaces are used, the base shall be a compacted flexible base constructed to the specifications of the City of Carrizo Springs to the depth shown in Table 3 with a Proctor density of not less than ninety-five (95) percent.

C.

Stabilized base: As alternate to the flexible base above, a compacted soil-cement base with a Proctor density of ninety-five (95) percent may be used, with soil-cement ratio and thickness to be approved by the city engineer.

D.

Asphaltic pavement: The compacted surface course shall be applied at the rates specified in Table 3. The paving mixture and construction methods shall conform to the specifications of the city for hot mix, hot laid asphaltic concrete, hot mix cold laid asphaltic concrete or cold mix limestone rock asphalt.

E.

Concrete pavement: All concrete pavement shall be Portland cement concrete of a depth and compressive strength specified in Table 3 and constructed in accordance with the specifications of the city. Reinforcing steel shall be 6 × 6 wire mesh or Number 3 round steel eighteen (18) inches on centers both ways.

F.

Curbs, curb and gutters: Curbs or combined curb and gutter sections, where required, shall be constructed of Portland cement concrete and installed in accordance with the specifications of the city on all streets within the subdivision along the lines and grades approved by the city engineer. Curbs or combined curb and gutter shall be provided on both sides of all streets within urban subdivisions and on the side of boundary streets adjacent to the subdivision.