§ 2. Road construction.

(a)

Subgrade. After the earth work has been completed, all storm drainage and other underground utilities have been installed under the roadbed, and the backfill in all such ditches thoroughly compacted, the subgrade shall be brought to the lines, grades and cross section shown on the plans. If any sections of the subgrade are composed of unsuitable or unstable material, such material shall be removed to the depth directed by the authorized representative of the city and replaced with suitable, thoroughly compacted material. When the street is to be used for construction traffic before the paving work is completed, a layer of No. 3 stone can be laid as a traffic surface if the developer so desires. This material shall not be used as part of the base material. It may be worked into the subgrade, or it shall be removed before the base course is set up for paving. Provision shall be made to drain low points in road construction when the final paving surface is delayed and to provide a break in the berm section when the curbing has not been constructed. Use 2½-inch or six-inch pipe sections to provide drainage under curb to side slopes.

(b)

Curb and gutter. Curb and gutter shall be vertical or rollback type having the sections and dimensions as follows:

(1)

Residential curbing.

a.

Concrete shall have a minimum strength of 3,000 pounds per square inch (psi) at 28 days.

b.

Typical minimum section shall be six inches by 24 inches by nine inches.

(2)

Industrial or commercial curbing.

a.

Concrete shall have a minimum strength of 3,000 psi at 28 days.

b.

Typical section shall be six inches by 30 inches by nine inches.

c.

Vertical-faced curbing only.

(3)

Construction methods.

a.

Line and grade shall be set by the developer's engineer or surveyor.

b.

One-half-inch expansion joints of premolded bitumastic expansion joint material shall be provided at all radius points and at intervals not to exceed 50 feet in the remainder of the curb and gutter.

c.

Intersection dimensions shall be as follows:

Street Type (Abutting)	Radii (feet)	Length Storage Lane (feet)	Taper (feet)
Arterial	40	150	50
Major collector	40	150	50
Minor collector	25	100	50
Local	25	100	50
Alleys	To be designated by city engineer

 

d.

Special curbing designs (center islands, etc.) shall individually be approved by the city engineer.

e.

Curb and gutter shall be set true to line and grade and finished by skilled workmen to the section shown on the plans.

f.

Inferior workmanship or construction methods resulting in unsightly curb and gutter will be cause for rejection of the finished work.

g.

When property fronting on an existing city road is subdivided for development, curb and gutter shall be required along said road.

(4)

Location. Curbing as required by the city engineer on existing city roads shall be located as follows:

Type Street	Location* (feet)
Arterial	24 plus curb and gutter
Major collector	24 plus curb and gutter
Minor collector	12 plus curb and gutter
Local	12 plus curb and gutter

 

*All distances shown are for minimum number of lanes. Additional lanes may be required to accommodate plans for future improvements or for turning movements.

Distances are measured from the centerline of the street to the front edge of the gutter. The cost of any catchbasins which must be constructed when an existing city road is required to be developed will be paid by the developer. All curbing shall be backfilled and landscaped.

(c)

Residential streets. Residential streets shall be built to the following standards:

(1)

Base material. The following types of base material may be used:

a.

Eight-inch crusher run stone. Cement stabilized, central mixed;

b.

Grades aggregate base course. The base course shall consist of mineral aggregate and soil mortar and may be a combination of natural deposit or a blend of the materials specified. All materials are subject to approval by the city engineer. If a blend of materials is used, they shall be blended through a base plant which meets the latest specifications of the Georgia state highway department. Minimum depth of course shall be six inches under a minimum of 1½-inch asphaltic concrete;

c.

Black base. The base course shall consist of asphaltic concrete as approved by the city engineer and shall conform to applicable specifications of the Georgia state highway department. Minimum base course shall be four inches under a minimum of two-inch asphaltic concrete.

(2)

Prime. After the base has been placed, mixed, compacted, shaped, inspected and accepted, it shall be primed with suitable asphaltic materials as specified by the city engineer.

(3)

Roadway surfaces. After the subgrade has been inspected and compaction tests approved, the six-inch aggregate base shall then be installed. The aggregate base shall be inspected and compaction tests [shall be] approved in the same manner as the subgrade. After the aggregate base is approved, a prime coat shall be installed at grade of 0.25 gallon/square yard with allowable time to cure. The roadway or street shall be surfaced with a minimum of two inches of asphaltic concrete binder GA D.O.T. Type B. After the binder is inspected and approved a tack coat consisting of AC-20 at a rate of 0.05 gallon/square yard shall be installed. The topping shall be installed after such tack coat and consist of a minimum of 1½ inches of asphaltic concrete topping GA D.O.T. Type F. There shall be a minimum of [a] two-foot overlap between the binder and topping. All asphaltic concrete will be mixed in an asphalt plant meeting the latest requirements of the Georgia State Highway Department.

(4)

Typical street section.

a.

Residential street width shall be as stated in the subdivision regulations.

b.

Residential streets shall have a 12-foot shoulder section behind both curbs at a grade of one-eighth inch per foot sloping toward the road.

c.

Cul-de-sacs on residential streets shall be a minimum of 50-foot radii of paved surface and 60-foot radii right-of-way when the developed length of such cul-de-sac is over 150 feet; cul-de-sacs 150 feet or less shall be provided at the closed end with a turnaround that may be a minimum 40-foot radii of paved surface and 50-foot radii of right-of-way.

(d)

Industrial streets. Industrial streets shall be built to the following standards:

(1)

After the subgrade has been inspected and compaction tests approved, the ten-inch aggregate base shall then be installed. The aggregate base shall be inspected and compaction tests approved in the same manner as the subgrade. After the aggregate base is approved, a prime coat shall be installed at grade of 0.25 gallon/square yard with allowable time to cure. The roadway or street shall be surfaced with a minimum of three inches of asphaltic base course. After the base course is inspected and approved a tack coat consisting of AC-20 at a rate of 0.05 gallon/square yard shall be installed. The binder shall be installed and consist of two-inch Type B. A tack coat shall be installed after the binder at the same rate specified. The topping shall be installed after such tack coat and consist of a minimum of two inches of asphaltic concrete topping GA D.O.T. Type E. There shall be a minimum of [a] two-foot overlap between the binder and topping. All asphaltic concrete will be mixed in an asphalt plant meeting the latest requirements of the GA D.O.T.

(2)

Four inches of crusher run stone treatment shall be used wherever unsuitable material is found in the subgrade.

(3)

Pavement width for industrial streets shall have no less than as follows:

Type Street	Minimum Right-of-Way (feet)	Minimum Pavement Width (feet)
Major	100	48 with 12-foot lane
Minor	80	36 with 12-foot lane

 

(4)

Cul-de-sac radii on industrial streets shall be a minimum of 60 feet of paved surface.

(5)

A minimum 12-foot shoulder behind both curbs at a grade of one-eighth inch per foot sloping toward the road.

(d)[(d.1)]

Office/commercial streets. Office/commercial streets shall be built to the following standards:

(1)

After the subgrade has been inspected and compaction tests approved, the eight-inch aggregate base shall then be installed. The aggregate base shall be inspected and compaction tests approved in the same manner as the subgrade. After the aggregate base is approved, a prime coat shall be installed at a rate of 0.25 gallon/square yard with allowable time to cure. The roadway or street shall be surfaced with a minimum of 3.5 inches of asphaltic concrete binder GA D.O.T. Type B. After the binder is inspected and approved a tack coat consisting of AC-20 at a rate of 0.5 gallon/square yard shall be installed. The topping shall be installed after such tack coat and consist of a minimum two inches of asphaltic concrete topping GA D.O.T. Type E. There shall be a minimum of [a] two-foot overlap between the binder and topping. All asphaltic concrete will be mixed in an asphalt plant meeting the latest requirements of the GA D.O.T.

(2)

Pavement width, shoulder dimensions and cul-de-sac radii on office/commercial streets shall have the same requirements as industrial streets.

(3)

All streets shall be open to traffic for a period of one year before being accepted by the city.

(4)

The city reserves the right to take core samples of the pavement and base at the owner's expense during this one-year maintenance period.

(5)

Cul-de-sacs on office/commercial streets shall be a minimum of 50-foot radii of paved surface and 60-foot radii of right-of-way when the developed length of such cul-de-sac is over 150 feet; cul-de-sacs 150 feet or less shall be provided at the closed end with a turnaround that may be a minimum 40-foot radii of paved surface and 50-foot radii of right-of-way.

(e)

Street landing requirements. All streets shall intersect at no more than a two percent grade for a distance of no less than 75 feet. This distance is measured from the intersection of the edges of pavement back to the first point of vertical intersection (PVI).

(f)

Street cuts. All utility construction plans within city right-of-way shall be reviewed and approved by the city community development department before construction begins. All trenches shall be backfilled and compacted the same day the trench is opened. Trenches under the paving shall be returned to 95 percent compaction. Trenches elsewhere shall be returned to 90 percent compaction. All trenches under paving shall be concreted with six inches beyond the edges of the trench and excavated to allow for the six inches of concrete and the 1½ inches of asphalt to be poured. The paving cut shall be widened to a minimum of 12 inches beyond the edges of the trench and excavated to allow for the six inches of concrete and 1½ inches of asphalt to be poured. The edges of the paving cut shall be smooth. A final wearing surface of 1½ inches of Type "E" asphaltic concrete shall be poured and rolled after the concrete is sufficiently cured.

(g)

Apartment and condominium streets. Apartment and condominium streets and associated storm drainage shall be constructed to residential street standards as set forth in these specifications.

(h)

Commercial areas. Commercial areas shall conform to the city's major thoroughfare plan for entrance into public streets.

(i)

Superelevation. Superelevation shall be provided as per state highway design for arterial and collector type streets.

(j)

Sight distance. Adequate horizontal and vertical sight distance shall be provided on all roadways as per AASHTO standards.

(k)

Sidewalks. When a development abuts a public right-of-way, sidewalks shall be required along the entire road frontage. Sidewalks will be required to be constructed on both sides of the road (if the development abuts both sides of the road) when the road is classified as an arterial, major collector or minor collector roadway. Sidewalks shall be constructed on one side of all internal streets within a subdivision. Sidewalk location and orientation may be altered under site specific conditions at the discretion of the city engineer.

Amenity areas must be accessible by sidewalks from the nearest sidewalk in a subdivision. All sidewalks must be installed prior to the acceptance of the subdivision by the city unless a performance bond is in place at the time of acceptance.

Commercially zoned developments shall provide internal sidewalks and crosswalks to provide connectivity to sidewalks on abutting rights-of-way.

Sidewalks shall be located a minimum of two feet from the back of curb. Sidewalk location may be varied at the discretion of the city engineer with prior approval.

Sidewalks constructed within a subdivision along streets classified as local streets shall have a minimum width of four feet and all others shall have a minimum width of five feet.

The concrete shall have a minimum compressive strength of 3,000 psi at 28 days and a minimum depth of four inches.

Builders are required to install sidewalk prior to issuance of a certificate of occupancy by the city.

(l)

Street markers. Street markers shall be green "Scotchlite" with white legends mounted on ten-foot round posts and shall be furnished and installed by the city at all street intersections.

(m)

Traffic signs. Traffic signs shall be placed by the sign and signal section of the public works department.

(n)

Guardrail. Guardrail shall be installed when warranted by speed design, roadside geometrics, grades or other roadside hazards. Guardrails shall begin in advance of the hazard or hazardous area by a sufficient length to prevent vehicle penetration behind the rail into the protected area.

(o)

Underground utilities. All utilities within the curbs shall be installed and the ditches backfilled and thoroughly compacted before any pavement or base is installed. All utility manholes and valve boxes shall be brought to the finished grade within the roadway section. All utility locations shall correspond to the typical layout.

(p)

Foreign material on streets. The developer and/or builders shall be responsible for keeping dirt, mud, building materials, concrete, etc., off of the pavement and curbing during construction of buildings in all developments covered by these regulations. Before the streets are accepted by the city, all litter and trash shall be removed from the dedicated rights-of-way and surrounding areas. No retaining walls or other structures shall be placed within the right-of-way.

(q)

Conformance with other regulations. Construction plans for all facilities covered by standard design specifications and the City of Smyrna subdivision regulations shall conform to the soil erosion and sediment control ordinance and the flood damage prevention regulations.

(Ord. No. 94-05, 4-4-94; Ord. No. 94-06, 4-4-94; Ord. No. 94-07, 4-4-94; Ord. No. 94-09, 6-6-94; Ord. No. 94-10, 6-6-94; Ord. No. 2002-11, 8-5-02)