This article is titled The Standard Design Specifications of Powder Springs, also referred to in this code as "standard details."

(a)

Unless otherwise specially set forth in this code or the standard design specifications of this article, all of the materials, methods of construction, and workmanship for the work covered in reference to street construction and storm drainage construction shall conform to the latest standard specifications of the Cobb County Department of Transportation, or if no such standard detail covers the subject improvement, the standard specifications of the Georgia Department of Transportation.

(b)

Design criteria and standards not specifically set forth in this Article specifically or this Development Code generally, and not addressed in county or state Department of Transportation specifications, shall conform to the latest edition of the AASHTO Policy on Geometric Design of Highways and Streets.

(a)

Graded aggregate base course. The base course shall consist of mineral aggregate and may be a combination of natural deposit or a blend of the materials specified. All materials are subject to approval by the public works director. If a blend of materials is used, it shall be blended through a base plant that meets the latest specifications of the Georgia State Highway Department Specification 815.

(b)

Thickness. Street base material shall conform to the thickness as required for the street type in table below.

(c)

Extent. The street base shall extend fully under curb and gutter at least 2" thick. For streets without curbs, the base shall extend at least 6" beyond the edge of payment.

(d)

Unsuitable material. Wherever unsuitable material is found in the subgrade, the unsuitable material shall be replaced with graded aggregate stone.

(e)

Pavement topping - prime. After the base has been placed, mixed, compacted, shaped, inspected and accepted, it shall be primed with suitable asphaltic materials as specified in Department of Transportation Specification 412.

(f)

Pavement topping - roadway binder. After the prime has been inspected and accepted, the roadway or street shall be surfaced with Type "B" binder as required for the street type in the table below.

(g)

Pavement topping - tack coat. Tack coat shall be applied on a prepared road surface according to the requirements of Georgia Department of Transportation Specification 413.

(h)

Pavement topping - final coat. Final topping shall consist of a course of Type "E" asphaltic cement as required for the street type in the table below.

(i)

Staged paving. If 2-stage paving for residential streets is approved by the public works director, the developer shall place the binder course on the street but may delay final paving. Prior to the expiration of the 2-year maintenance bond, the binder surface will be primed with suitable asphaltic materials as specified in Department of Transportation Specification 412. After the prime has been inspected and accepted, the roadway or street shall be surfaced with a minimum 1½" of Type "E" asphaltic concrete wearing surface. No surface treatment pavement as a finished wear surface will be accepted. All asphaltic concrete will be mixed in an asphalt plant meeting the latest requirements of the Georgia Department of Transportation.

Note: See also standard detail 400.02 in article 21 of this development code.

Sight distance requirements at intersections shall be provided in the table below. Distances shall be measured from the centerline of ingress/egress road extending to either side of the abutting street along thoroughfare a distance of 20' from the edge of the thoroughfare. Intersections within subdivisions shall be designed for a minimum sight distance of 160', unless the required design speed exceeds 25 miles per hour. The design speed for sight distance requirements at entrance intersections shall be the existing city or county road speed limit.

Minimum Sight Distance

Note: the public works director may apply Cobb County/GDOT/AASHTO standard for sight distance in lieu of city standard.

The sight distance for horizontal curves at subdivision entrances is determined by the line of sight available 3.5' above the road surface. The sight distance is measured along the existing edge of pavement beginning at the centerline of the proposed entrance and ending where the line of sight intersects it. The line of sight is the projected line of visibility beginning at the entrance centerline and tangent to an obstruction 3.5' above the road surface. Examples of obstructions are vegetation, ground cover, signs, existing topography, etc.

All changes in grade shall be connected by a vertical curve so constructed as to afford a minimum sight distance, said sight distance being measured from the driver's eyes, which are assumed to be 3.5' in height above the pavement surface, to an object 2' high on the pavement.

Minimum length of vertical curves (for interior subdivision thru-streets and long cul-de-sacs) shall be per table below:

Where a deflection angle of more than 10 degrees occurs in the alignment of a street, the radius of curvature of the center line of said street shall be not less than as specified in the table below:

Curved streets shall have a minimum tangent of 100' at intersections as measured from the centerline of cross streets. A tangent of a least 200' in length shall be introduced between reverse curves on collector streets (and at least 100' on local streets).

Temporary turnarounds shall consist of a tack coat and one inch of asphalt.

(a)

Local residential streets. Local residential street curbs shall be Portland cement concrete, 6" x 24" x 9" vertical for roll back type (see standard detail), with a minimum strength of 3,000 psi at 28 days.

(b)

Collector and local commercial or industrial streets. Curbs along collectors and local commercial or industrial street curbs shall be Portland cement concrete, 6" x 24" x 12" vertical type only, with a minimum strength of 3,000 psi at 28 days.

(c)

Additional specifications. Curbing along streets shall meet the following standards:

(1)

Developer's engineer or surveyor shall set line and grade.

(2)

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

(3)

The public works director shall individually approve special curbing design (center islands, etc.).

(4)

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

(5)

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

(6)

All curbing shall be backfilled and grassed.

(7)

Adequate storm drainage structures shall be provided. The curb and gutter shall be constructed so as to present a smooth, even line both horizontally and vertically.

(d)

Valley gutter. A valley gutter may be used across a driveway at its intersection with a street. However, valley gutters shall not be allowed across streets at street intersections unless specifically approved by the public works director.

(a)

Streets with curb and gutter. On streets with curb and gutter, the shoulders shall slope ¼" to the foot toward the roadway for at least 13' (for residential streets, 17' for industrial/commercial streets) from back of curb, and no more than 1/8" to the foot for the remainder of the right-of-way width.

(b)

Streets with swale ditch drainage. On streets with swale ditch drainage, the shoulders shall slope ¾" to the foot away from the roadway for at least 5' to the drainage channel. The maximum slope for the drainage channel shall be 2' of run for each 1 one foot of fall, with a minimum 2' wide channel at the bottom of the swale.

(a)

Minimum pavement width (not including curbs) and right-of-way to accommodate acceleration and deceleration lanes at development entrances are shown on the following table:

(b)

Lane length is measured 150' from radius point to beginning of taper (per standard drawing 400.05; see article 21 of this development code). Tapers are 50'. Vertical face curb and gutter is required through the radii, excluding the tapers. The additional lane can be stopped at the projected property line if there is inadequate right-of-way or excessive cut or fills to install the lane. In this case, the tapers would start at the projected property line unless excessive cut or fills would encroach on the right-of-way limits of the abutting property.

(c)

The cost of any catch basins that must be constructed when an existing city or county road is required to be developed will be paid by the developer.

(d)

Utilities (if required by the utility provider) and drain pipes shall be relocated at the developer's expense outside of the acceleration/deceleration lanes. Waterlines can remain beneath the additional lanes.

(e)

The area behind all curbing shall be backfilled and landscaped.

All utility construction plans within city right-of-way shall be reviewed and approved by the public works director prior to utility construction or placement.

All private utilities that will cross under pavement shall be installed completely throughout the subdivision prior to any roadway base being applied. Installation of approved utility sleeves shall be considered as an alternative.

(a)

Policy. The city's policy is that no existing city roads can be open cut unless unusual circumstances warrant it as approved by the public works director. All utilities beneath pavement shall be installed and the ditch backfilled and thoroughly compacted before any pavement or base is installed, or the pipes shall be bored if installed after street construction.

(b)

Trenching. If the city allows open cutting all trenches under existing paving shall be backfilled and compacted in 6" lifts and excavated to allow for 8" of 3,000 psi concrete and 1½" of asphaltic concrete to be placed. Where permitted, all trenches for underground utilities shall be backfilled and compacted the same day the trench is opened. Trenches under the paving shall be returned to 95% compaction. Trenches elsewhere shall be returned to 90% compaction.

(c)

Width of paving cut. The paving cut shall be widened to a minimum of 9" beyond the edges of the trench and excavated to allow for the 8" of 3000 psi concrete and 1½" of asphaltic concrete to be placed. The edges of the paving cut shall be smooth. A final wearing surface of 1½" of Type "E" asphaltic concrete shall be poured and rolled after the concrete is cured. See Standard Detail 400.13 for illustration.

(d)

Utility manholes and valve boxes. All utility manholes and valve boxes shall be brought to the finished grade within the roadway section.

(a)

Sizing and location of all existing and proposed drainage structures shall be the responsibility of a registered professional engineer, subject to approval by the public works director.

(b)

The drainage formula used in determining size of drainage structures shall be determined by the developer's engineer, according to accepted engineering practice, subject to approval of the public works director.

(c)

The 25-year storm event shall be used in designing the storm drains. In cases where a spring, creek, or other watercourse traverses the property, the 100-year storm event will be used for design.

(d)

All stormwater detention facilities shall be designed per the requirements of article 11 of this development code.

(e)

The hydraulic grade line associated with the 100-year storm peak flows of all piped collection systems shall be at or below the structure inlet elevation or the structure rim elevation or the finished grade elevation, whichever is lower, for all storm pipes and structures throughout the system.

(f)

The hydraulic grade line associated with the 25-year storm peak flows of all piped collection systems shall be at or below the crown of the pipe throughout the system.

(Ord. No. 2025-004, § 1 (Exh. C), 4-7-2025)

The reservoir routing method or an equivalent method shall be used in sizing detention ponds. The bowstring method is not acceptable.

An emergency overflow device (which does not include the throttling device) for a detention pond shall be designed to pass the 100-year peak developed inflow without overtopping the dam.

Pond discharge locations shall be in defined drainage ditches.

All development plans will require a hydrology study certified by a registered engineer. The developer's engineer shall include in the hydrology study a discussion of existing conditions downstream of the detention pond, including the flow capacity of downstream drainage structures, and an explanation of how downstream property owners will not be adversely affected by the concentrated runoff. If the downstream system is inadequate, the developer is required to either improve the downstream drainage structure or provide additional storage in the detention facility.

If there is an existing storm drainage system within 150' of the discharge point of the outlet pipe for the pond, then the developer shall extend the outlet pipe and tie-in to the existing system.

The steepest fill slopes shall be 3:1, and cut slopes shall be no steeper than 2:1. Slopes proposed to be steeper require approval of the director of public works.

If a pond is deeper than 4', a chain link or privacy fence shall be required. The fence shall be 6' high. Fence posts shall be set in concrete 10' on centers. There shall be a minimum 10' wide gate for access. The fence shall not be installed across the slope of a dam or dike, but installed completely around the pond and including suitable access.

Storm drainage pipes shall be sloped so as to maintain a minimum velocity of 3 fps so that sediment will not collect.

State Department of Transportation Standard 1030D (or most current) shall be used in determining class (concrete) or gauge of pipe under fill, method of backfilling and pipe installation.

Storm sewer catch basins, drop inlets, manholes, and junction boxes shall be designed by the developer's engineer to Georgia Department of Transportation Standards and subject to final approval by the public works director. Catch basins shall be located outside of intersection radii unless unusual circumstances cause undue hardship, in which case the public works director may waive this requirement.

Street water runoff shall be designed using the gutter spread formula and shall be limited to a maximum distance as follows:

(a)

500' on grades up to 7%.

(b)

400' on grades from 7% to 10%.

(c)

250' on grades over 10%.

(d)

Cul-de-sacs on downhill street grades shall require catch basin throat design and cul-de-sac grading detail.

Subdrainage will be installed to control the surplus ground water by intercepting side hill seepage or by lowering or regulating the ground water level where such conditions exist.

Bridges shall be designed for a 100-year storm event.

Provide riprap at all downstream discharge points of storm drains.

Exit velocities from storm drain pipe for the 50-year storm shall not exceed 10 fps without additional energy dissipators (not including required riprap).

If a new or existing lake is proposed as a part of a subdivision or land development, the developer shall be required to submit a breach analysis and show the dam breach zone on the plans.

When located under a street, cross-drain pipes shall be no less than 18" in size. No storm drain pipe running parallel to the existing primary road shall be located beneath any acceleration/deceleration lane. The public works director may modify or waive this requirement if unusual circumstances exist, such as topography.

The inlet and outlet end of all storm drain pipes (except driveway pipe) shall have either flared-end sections or concrete headwalls that meet the standards of Georgia Department of Transportation 1120 or 1125.

(a)

For storm drain pipes 36" or smaller, pipes shall extend 20' past the rear of any building. For storm drains larger than 36", extend pipes 20' past the rear of any buildings and size the drainage ditch on each end of the pipe to limit the runoff velocity to less than 5 fps, or riprap the ditch.

(b)

For pipes less than 42", the maximum continuous length of pipe shall be 300'.

Junction boxes having access to the pipe shall be constructed to meet the requirements of State Department of Transportation Standard 1030D (or most current).

All man-made ditches between storm drain pipes and downstream of storm drain pipe shall be designed by a registered professional engineer. The ditch profile and cross-sections every 50' shall be shown on the plans. The plans shall show the velocity and flow at each cross-section. Stormwater velocity shall not exceed 5 fps unless the ditches are lined.

Only concrete pipe shall be used within city maintained easements, or street rights-of-way, whether public or private. Concrete pipe shall be reinforced within the right-of-way but may be plain pipe outside of the right-of- way.

Only reinforced concrete pipe shall be used for all dams unless the Georgia Safe Dams Program requires another material.

Metal pipe shall be fully coated and only used outside of the right-of-way.

High density polyethylene (HDPE) pipe shall comply with Georgia Department of Transportation or manufacturer specifications.

(Ord. No. 2025-004, § 1 (Exh. D), 4-7-2025)

(a)

Pipe installation shall conform to Georgia Department of Transportation Standard Specifications for construction of roads and bridges.

(b)

Before any traffic over a storm drain is allowed, the developer shall provide an adequate depth and width of compacted backfill to protect the structure from damage or displacement.

(c)

The developer shall remove any debris or silt that constricts the flow through a pipe as often as necessary to maintain drainage. All pipe structures shall be cleaned before the work is accepted.

(d)

Any damage or displacement that may occur due to traffic or erosion shall be repaired or corrected at the developer's expense.

(a)

Minimum clearance shall be one foot between the bottom of the base or sub-base, if used, and the exterior crown of the culvert.

(b)

There shall be a minimum of 6" between underground utilities and the exterior crown of culverts.

Trench construction for storm drainage pipe shall be in accordance with State Department of Transportation Standard 1030D (or most current).

Where a wet weather stream exists between the proposed road and 20' into the lot, the design professional shall size the driveway culvert as if the driveway was at the lowest point on that lot. The construction plans shall show the minimum driveway pipe size required.

Changes in construction plans caused by field conditions shall be made at the direction of the public works director, with the cost of such changes to be paid by the developer.

[Insert Local Jurisdiction Name]
Runoff Reduction Infeasibility (RRI) Form for
Determination of Infeasibility

Design Professional Primary Contact (Name/Email/Phone): _____
_____

Description of Site/Land Development Application Number: _____
_____

Address: _____
_____

Size (acres): _____
_____

Maximum Practicable Runoff Reduction Volume*: _____

*If any of the stormwater runoff volume generated by the first 1.0 inch of rainfall cannot he reduced or retained on the site, due to site characteristics or constraints, the remaining volume shall be increased by a multiplier of 1.2 and shall be intercepted and treated in one or more best management practices that provide at least an 80 percent reduction in total suspended solids.

GENERAL SUPPORTING DOCUMENTATION

All General Supporting Documentation must be included with this RRI Form for the submittal for a Determination of Infeasibility to be considered complete. Please check each item below to confirm it has been included in the submittal package.

□

Stormwater Concept Plan that has been developed based on site analysis, and natural resources inventory (including impracticability) in accordance with Section 2.4.2.5 of the GSMM

□

GSMM Stormwater Quality Site Development Review Tool for the Stormwater Concept Plan

□

Please include justification that the site cannot accommodate best management practices that rely on evapotranspiration and reuse such as rainwater harvesting or green roofs

SITE CONDITION APPLICABILITY

(descriptions are in Policy on Practicability Analysis for Runoff Reduction)

Please check each applicable item below and confirm the supporting documentation has been included in the submittal for a Determination of Infeasibility.

*Note: A determination of infeasibility cannot be granted solely for economic hardship and must be present with another site condition. Additionally, a determination of infeasibility for economic hardship may only be allowed for up to 50 percent runoff reduction volume.

STORMWATER RUNOFF QUALITY/REDUCTION SUMMARY

Maximum Practicable Runoff Reduction Volume*: _____

Remainder of Volume treated by Water Quality Best Management Practice: _____

*If any of the stormwater runoff volume generated by the first 1.0 inch of rainfall cannot be reduced or retained on the site, due to site characteristics or constraints, the remaining volume shall be increased by a multiplier of 1.2 and shall be intercepted and treated in one or more best management practices that provide at least an 80 percent reduction in total suspended solids.

Design Professional Printed Name _____

Design Professional Signature _____

(Ord. No. 2023-008, § 1(Exh. A), 8-21-2023)

Residential water supply for domestic use shall be in accordance with the following table "Instantaneous Water Demands for Residential Areas," and at a minimum pressure of 20 psi.

Instantaneous Water Demands for Residential Areas

All plans for development must meet all applicable fire protection codes.

The following minimum quantities of water in gallons per minute (gpm) are required prior to development of the property:

(a)

Residential, single-family: 500 gpm for 30 minutes.

(b)

Residential, Multi-family: 750 gpm for 30 minutes.

(c)

Shopping centers: 750 gpm for 30 minutes.

(d)

Motels, light industry, and schools: 750 gpm for 30 minutes.

(e)

Heavy industry, large/tall buildings (warehouses, office buildings, institutional): Minimum 1,000 gpm for 45 minutes.

Spacing of fire hydrants shall be as follows. Hose lay distance is defined as being measured along the route a piece of fire apparatus must travel in laying a fire hose from the fire to the fire hydrant.

(a)

Residential, single-family. Single-family residential developments shall have a maximum hose lay distance of 500' from the hydrant to the most distant building served by that hydrant. Fire hydrants shall normally be located at all intersections, and shall be located at the end of the line on all cul-de-sacs.

(b)

Residential, multi-family. Fire hydrants shall be spaced not more than 500' apart with additional fire hydrants located as necessary to permit all portions of buildings to be reached by hose lays of not more than 300' in length.

(c)

Shopping centers, malls, etc. Fire hydrants spaced not more than 300' so all portions of buildings can be reached by hose lays of not more than 300' in length.

(d)

Motels, light industry, and schools. Fire hydrants spaced not more than 500' so all portions of buildings can be reached by hose lays of not more than 300' in length.

(e)

Heavy/tall buildings. Fire hydrants spaced not more than 300' apart so any portion of the building can be reached by hose lays of not more than 300' in length.

(a)

Residential, single-family: Single-family residential developments shall use a minimum of 6" diameter mains unless larger size mains are called for in a water system master plan.

(b)

Residential, multi-family: Water mains of at least 8" diameter pipe shall be installed; 6" diameter pipe may be used only where it completes a gridiron and then only up to 600' in length between interconnecting mains of approved diameter.

(c)

Large shopping centers, malls, etc.: Water fire mains to be no less than 8" diameter.

(d)

Commercial areas: Commercial areas with less than 200,000 square feet use water main no less than 8" diameter.

(e)

Motels, light industry, and schools: no less than 8" diameter.

(f)

Heavy industry, large/tall buildings: no less than 10" diameter.

The public works director or his designated representative has the authority to waive the minimum water main sizes required in section 21-75, provided that: a note is provided on plans as follows: "I have designed the water service installation for this facility in accordance with all applicable City water specifications in regards to fire flows and these conditions have been met." This note is to be signed and stamped by the engineer providing the calculations. Further, the development applicant provides the city with a copy of the calculations.

Water mains and fire hydrants shall be installed by the developer and approved by the public works director under water pressure and ready for fire fighting before any sheathing may be installed on walls and roof.

(a)

Water lines shall be metered as required by the water provider.

(b)

Each residential unit shall be individually metered.

(c)

Water meters shall be located at the edge of the street right-of-way.

(a)

On existing roads, water lines shall be located on the south and west side of the road, within 2' of the right-of-way with a minimum bury of 42" below the level of the roadbed. Permission must be obtained from the public works director to vary from this requirement.

(b)

Water lines on new residential streets shall be located on the south and west side of the street, 5' from the back of the curb with a minimum bury of 48". For water lines on new streets, all curbing must be installed before any water lines are installed.

(a)

Service laterals shall be located with a minimum bury of 48" within the right-of-way and shallowing to a bury of 12" at the water meter location.

(b)

Service laterals crossing any roads will be placed inside a minimum 1½" diameter casing.

(c)

A "W" shall be sawed into the curb where each service tap is made for permanent location.

(d)

Copper tubing shall be used for all service laterals. Ductile iron shall be required in all other locations.

(e)

Water valves at intersections shall be located behind the curb.

(f)

The required number of valves shall equal the number of streets in the intersection, minus one.

(g)

A gate valve and a minimum of 36' of pipe shall be provided at the end of all lines for phased developments. The end of the line shall be provided with temporary plug and blocking.

(h)

All water lines shall be looped to prevent accumulation of stagnant or contaminated water.

(a)

Any person making application for new fire service connections with private fire hydrant(s), hand hose connection(s), or sprinkler head(s) will be required to have an underwriter approved detector check meter or a factory mutual fire line meter installed as a part of the fire service system.

(b)

When unauthorized water is used through a detector check meter in 3 or more billing periods in one calendar year, it shall be replaced with a factory mutual fire line meter. Unauthorized use of water is defined as non-fire fighting water and/or water use without prior notification and approval of the city.

(c)

All domestic water supply must be metered with proper meter.

(d)

Installation of detector check meters or factory mutual fire line meters as required by this section will be handled by the developer under supervision of the public works director. The cost of installation will be at a rate established for each individual site.

(e)

The public works director shall have the authority to cut off water service to buildings whose owners refuse to comply with the provisions of this section upon 60 day notification.

(f)

The regular monthly fire service standby charge shall be continued for fire service installation having a detector check or mutual fire line meter. The water that is measured by the detector check meter will be billed at 5 times the normal water charge. If the services of legal counsel are required to collect bills, the cost of counsel shall be added to the billing.

(a)

Ductile iron pipe shall be designed in accordance with ANSI A21.50-81 and manufactured in accordance with ANSI A21, 51-81. Wall thickness class shall be Class 350 or latest revision.

(b)

Ductile iron pipe shall have an outside asphaltic coating per ANSI A21.51-81. Pipe shall have standard cement lining inside with asphaltic seal coat per ANSI A21.4-80.

(c)

Pipe joints, except where restrained or flanged joints are specified, shall be push-on or mechanical joint type, and pipe shall be in 18' to 20' nominal lengths with standard deflection pipe sockets. Where restrained joints are shown or specified on pipe larger than 12" diameter the joints shall be "Lock-Fast," lock-ring or equal.

Service pipe shall be copper service pipe, type K, soft temper, seamless copper tubing, conforming to Federal Specification WW-T-T00. Flared joints will be used.

Steel casing pipe, where specified, shall be steel pipe conforming to A.S.T.M. Designation A-139, Grade B, electric fusion welded steel pipe. The pipe shall have a minimum tensile strength of 35,000 psi. The exterior and interior of the pipe shall have a coal tar varnish coating.

Fittings shall be ductile iron furnished in accordance with ANSI Specifications A21.10 (AWWA C110), latest revision, and shall be a minimum of 250 psi pressure class rating. Joints shall be mechanical joint with ductile iron ring or retainer glands conforming to ANSI Specification A21.11 (AWWA C111), latest revision. Cement mortar lining shall be furnished for pipe.

Butterfly valves (valves 12" and larger) shall be bubble-tight closing at the rated pressure with flow in either direction, and shall be satisfactory for applications involving throttling service and frequent operations or operations after long periods of inactivity. Valves shall meet the full requirements of AWWA Standard C504-74 for 150 psi working pressure and shall be suitable for above ground or buried service.

(a)

All interior ferrous surfaces of valves larger than 12" shall have a special epoxy coating meeting the requirements of AWWA C550.

(b)

Valve bodies shall be equipped with integrally cast mechanical joint ends meeting ANSI A21.11 (AWWA C111). Mechanical joints shall be fitted with retainer glands with set screws on ductile iron pipe.

(c)

Butterfly valves installed underground shall come equipped with the manual operator specified in the following subsection.

(d)

Manual operators shall be of the traveling nut, self-locking type and shall be designed to hold the valve in any intermediate position between fully open and fully closed without creeping or fluttering. Operators shall be equipped with mechanical stop-limiting devices to prevent overtravel of the disc in the open and closed positions. Valves shall close with a clockwise rotation. Operators shall be fully enclosed and designed for buried operation.

Valves 10" and smaller shall be gate valves. These valves shall be non-rising stem design, iron body, bronze mounted and have double disc and parallel seat. Valves shall be designed for a minimum working pressure of 200 psi and shall have 2" square operating nuts, except in meter vaults where handwheels shall be installed. Valves shall have non-rising stems, shall open when turned to the left and shall meet AWWA Specifications. Class 150 valves with flanged connections shall have one 125 pound flanges conforming to ANSI B16.1, and Class 250 valves with flanged connections shall have 250 pound flanges. Mechanical joints shall be fitted with retainer glands with setscrews on ductile iron pipe. Gate valve shall be manufactured per city specifications.

Valve boxes for valves shall be approved standard cast iron, adjustable-shaft boxes having a minimum shaft diameter of 5¼". The casting shall be coated with 2 coats of coal tar pitch varnish. The lids of all boxes shall bear the word "Water" or the letter "W." Boxes shall meet city specifications.

(a)

Air and vacuum relief valves shall be cast iron body and covers with bronze trim, stainless steel float, Buna-N-Seal, and shall be designed for a minimum working pressure of 150 psi.

(b)

The valve shall be designed to exhaust large quantities of air during the filling period, and small quantities of air that collect in the line while operating under pressure. The valves shall be equal in all respects to Clow Corporation combination air release valves. Valves shall be of the size shown on the plans and called for in the proposal.

(c)

Gate valves between water main and air relief valve shall be all bronze, solid wedge with screw connection equal to Jenkins Company's Figure #370.

(d)

Meter box shall be manufactured per city specifications.

(e)

Air and vacuum release valves to be connected to the service main with tubing as shown in the standard detail drawings.

(a)

All fire hydrants shall be designed and manufactured to comply with the latest specifications of the American Water Works Association (AWWA). They shall be designed for 150 pounds working pressure. The hydrants shall be of simple design, easy to operate, effectively and positively drained and protected from damage by freezing, and convenient for repairing and replacing parts.

(b)

Hydrants shall be equipped with one 4½" diameter pumper nozzle and two 2½" diameter hose connections, which shall have threads meeting the latest requirements of the State Fire Insurance Commission. Hydrants shall have a safety flange on the barrel and coupling on the valve stem, to prevent damage to barrel and stem in case of traffic accident. Hydrants shall be Mueller Company's centurian traffic model, M & H Style 129 traffic model, or American Darling Model B62B, or U.S. Pipe Manufacturer's Sentinel model or East Jordan Iron Works 5CD250, or equivalent as determined by the public works director.

(c)

The construction to the main line shall be with mechanical joint locked hydrant tee equal to American Cast Iron Pipe Company A-10180. The connection at the base of the hydrant shall be mechanical joint with ductile iron retainer gland, for Class 150, centrifugally cast, 6" cast iron pipe. The valve opening shall meet the requirements of the AWWA Specifications for 4½" hydrant. The valve, valve seat and inner working parts shall be easily accessible. The depth from the surface of the ground to the bottom of the connecting pipe shall be 36". The distance from the ground to the hose nozzle shall not be less than 24". Each hydrant shall be neatly painted with a red reflective paint.

(d)

Each hydrant shall be tested to 150 psi. The first test shall be made with the valve closed. The second test shall be made with the main valve open but all nozzles closed. While this test is being carried on, the hydrant shall be subjected to a hammer test. Any hydrant showing defects by leakage, sweating or otherwise shall be rejected. The barrel and all parts shall withstand these tests. These tests shall be made in the field after the hydrants are installed.

Saddles shall be either Smith Blair 313 or 311, Dresser Style 194, or Clow Style #3407 for A.C. and D.I.P. and Style 3401 for P.V.C.

Mechanical joint plugs shall be similar and equal to F-1035 by the Clow Corporation.

Pipe connections between new pipe and existing pipe shall be made with Dresser Style 90 long steel couplings for pipe sizes 2" and below; for pipe sizes above 2" use M.J. solid sleeves.

All metal parts of curb stops shall be made of bronze. The stops shall be Ford B23-332 or Mueller padlock wings for flared copper service pipe. The cock shall be operated with a combined cap and tee and shall open when turned counter-clock wise.

Corporation cocks shall have threaded inlet and outlet connection for flared copper service pipe. All metal parts of the cock assembly shall be made of bronze. The cock shall be operated with a tee head and shall open when turned counter-clockwise. The cock shall be a Mueller H-15000, a Hayes 5200, a Ford F600, or approved equal.

P.V.C. casing pipe shall be used for long-side services and the type shall be Schedule 40.

Meter boxes shall be plastic boxes with cast iron lids.

Tapping valves shall be Mueller, M.J. Type, 200 psi, H-665, or equal.

Tapping tees shall be Mueller, M.J. Type, 200 psi, H-616 or equal, for pipe size as shown.

Sewers shall be designed as separate sanitary sewers only in which rainwater from roofs, streets, and other areas and groundwater from foundation drains are excluded. Overflows from sewers shall not be permitted.

Sewer systems should be designed for the estimated ultimate tributary population. Tributary population is considered to be all areas upstream of the discharge point of the system being designed. Sewers will be designed and installed to the uppermost property line of the development being served. Consideration should be given to the maximum anticipated capacity of institutions, industrial parks, etc.

(a)

In determining the required capacities of sanitary sewers, the following factors should be considered: maximum hourly sewage flow; additional maximum sewage or waste flow from industrial plants; ground water infiltration; topography of the area; and depth of excavation.

(b)

New sewer systems shall be designed on the basis of an average daily flow of sewage of not less than 400 gallons per household per day. Sewers should be designed to carry the per capita flow when flowing one-half full. Normally, all sewers shall be designed with a peaking factor of not less than 2½ and this may be increased upon the direction of the reviewing engineer. When deviation from the foregoing per capita rates is demonstrated, a description of the procedure used for design shall be included.

No sewer shall be less than 8" after leaving the uppermost property line to be served.

(a)

Any sewers installed in the street shall be sufficiently deep to provide 5' of cover at the inlet end of all service laterals at the street right-of-way, and over any part of the main or service within the street right-of-way.

(b)

Any sewers on off street easements shall have a minimum of 3' of cover unless cast iron or ductile iron pipe is used. Filling over the pipe to obtain minimum cover is not allowed if the fill will impede the natural flow of surface water or will cause an erosion problem.

(a)

All sewers shall be so designed and constructed to give mean velocities, when flowing full, of not less than 2' per second based on Kutter's formula using an "N" value of 0.013. The following are the minimum slopes which should be provided; however, slopes greater than these are desirable. These minimum slopes will be used only when sufficient flows are expected to maintain a velocity of 2' per second and maintain a cleaning action in the line.

Minimum Slope of Sewer by Size
(Slope in feet per 100 feet)

(b)

Sewers shall be laid with uniform slope between manholes.

(c)

Sewers on 20% slope or greater shall be cast iron or ductile iron pipe and shall be anchored securely with concrete anchors to prevent displacement by erosion or shock.

(d)

Maximum slope of sewers shall be 30% and sewers shall be designed at less than 20% whenever possible.

When a small sewer is connected to a large one, the connection shall not be lower than matching the 0.8 depth point of both sewers to the same elevation. For example, when connecting an 8" pipe to a 60" pipe a point 6.4" above the invert of the 8" pipe shall not be lower than a point 48" above the invert of the 60" pipe.

All sanitary sewer pipe up through 15" diameter must be Polyvinyl Chloride (PVC), Ductile Iron Pipe (DIP), or Steel Pipe, except where DIP or Steel Pipe is designated. For 18" diameter pipe and above, the contractor may have the option of using either High Density Polyethylene (H.D.P.E.), Polyvinyl Chloride (P.V.C.), Reinforced Concrete Pipe (R.C.P.), Ductile Iron Pipe or Steel Pipe, except where Ductile Iron Pipe (DIP) or Steel Pipe is specifically shown on the plans. All pipe shall be constructed with a minimum Class "C" bedding.

(a)

Ductile iron sewer pipe shall be required at all utility crossings with less than 2' of clearance, in cross country locations where cover is less than 3', in streets where cover is less than 5', in fills, and where PVC sewer pipe has more than 18' of cover.

(b)

Ductile Iron Pipe shall be designed in accordance with ANSI Specification A21.50-81. The thickness and class of the pipe shall be governed by ANSI Specification A21.50-81.

(c)

Pipe shall be manufactured in accordance with ANSI Specification A21.51-81 latest revision.

(d)

Pipe shall be coal tar epoxy lined and seal coated with approved bituminous seal coat in accordance with AWWA C151, latest revision. Coal tar epoxy lining shall adhere to the specifications of this Division.

(a)

The lining material for ductile iron pipe and fittings shall be Koppers Bitumastic No. 300-M coat tar epoxy, Sikagard 62 or approved equal. Two coats of different colors, each 8 to 10 dry mils thick shall be applied in accordance with the manufacturer's recommendations to obtain a minimum dry film thickness of 16 to 20 mils. Each pipe joint shall be marked with the date the coating was applied and its numerical sequence of application on that date. A permanent marker of identifiable color shall be used. The coating shall be allowed to cure for a minimum of 5 days at temperatures of 70°F to 100°F before pipe installation. The contractor shall submit test reports verifying the dry film thickness and the thoroughness of the coating.

(b)

Each joint shall be thoroughly sealed with the epoxy coating material during installation to provide a continuous coating throughout the pipe and allowed to cure.

DIP joints shall be of the bell and spigot type with push-on joints, conforming to ANSI Specification A21.11 or mechanical joints.

The contractor shall provide unplasticized polyvinyl chloride (PVC) plastic gravity sewer pipe meeting the requirements of ASTM D3034 (latest revision) in the sizes shown unless otherwise indicated on the contract documents.

Pipe and fittings shall meet the requirements as specified under ASTM D3034 (latest revision) for pipe through 15" and ASTM F679 for pipe 18" through 27". All pipe and fittings shall be suitable for use as a gravity sewer conduit. Bell joints shall consist of an integral wall section with elastomeric gasket joint that provides a watertight seal. Standard laying lengths shall be 20' (± one inch). The pipe shall be capable of passing all tests that are detailed in this specification.

Minimum wall thickness shall be as provided in the following table:

Thickness of PVC Sewer Pipe Wall

All fittings and accessories shall be manufactured and furnished by the pipe supplier. They shall have bell and/or spigot configurations compatible with that of the pipe and shall have an equivalent wall thickness.

The contractor will be required to furnish a written outline of the manufacturer's quality control program for the Engineer's approval prior to shipping any pipe to the project. Before installing any pipe the contractor shall furnish written certification that all pipe through 15" meets ASTM Specification D3034 and for 18" through 27" must meet ASTM F679. At least one sample from each 100 pieces of pipe furnished shall be subjected to each test outlined under Section 8 of ASTM D3034. The samples will be tested by an independent laboratory approved by the Engineer, and a certified copy of results will be furnished to the Engineer. If any test is not met then 9 additional tests of that property will be ordered, and if any of these 9 tests are not met, the manufacturer will not be allowed to furnish materials for this project. The cost of all testing shall be included in the contractor's bid proposal and no pipe shall be installed until the testing is complete and approved by the Engineer.

Minimum "pipe stiffness" (F/Y) at 5% deflection shall be 46 psi for all sizes, when tested in accordance with ASTM Standard Method of Test D2412 (latest edition), to determine the "External Loading Properties of Plastic Pipe by Parallel Plat Loading." There shall be no evidence of splitting, cracking, or breaking at a deflection of up to 30% of the original diameter.

There shall be no evidence of flaking, swelling, or disintegration when the pipe material is tested in accordance with ASTM D2152, "Quality of Extruded Poly (Vinyl Chloride) pipe by Acetone Immersion."

Pipe and fitting joints shall comply with ASTM D3212 (latest edition) for "Joints for drain and Sewer Plastic Pipes Using Flexible Elastomeric Seals." Joint assemblies shall not leak when subjected to both an internal and external hydrostatic test at equivalent pressures of 10.8 psi gauge for a period of one hour. Pipes shall be tested in straight alignment, axially deflected position, and by shear load test as otherwise defined in paragraphs 7.2, 7.3, and 7.4 of ASTM D3212.

(a)

PVC pipe will be installed in accordance with ASTM D2321 (latest revision).

(b)

In any area where the pipe is below existing ground water level, the contractor will embed PVC pipe in sand or graded gravel. No special compaction requirements will be necessary; however, the sand or gravel must extend from 6" below the pipe to 12" above the pipe, and the material must be firmly placed under the pipe haunches.

(c)

When embedding PVC pipe in friable, compressible soils (e.g., silt, clay, sandy clay, silty clays, etc.), special care must be exercised to provide a uniform (undisturbed or fully compacted) trench bottom. Additionally, the backfill must be compacted to 95% standard proctor in 6" to 8" lifts to 12" above the top of the pipe. Initial backfill shall be compacted to the densities outlined in D2321. The engineer may require up to 10 random compaction tests to insure compliance with D2321.

(d)

If any material tested is less than the required density, the contractor shall re-compact said material at no additional cost to the owner, and the engineer shall then have the right to additional compaction tests at the expense of the contractor to ensure compliance with D2321.

(e)

The contractor shall use SDR-35, for pipe with 0 to 20' of fill. PVC pipe cannot be used with more than 20' of fill.

(a)

Vertical deflection of installed pipe shall not exceed 7½% of the undeflected diameter as defined in Table X1.1 of ASTM D3034.

(b)

Each segment of line (except service lines) will be tested at the end of each month just prior to submitting for payment on that segment. Upon completion of the pipe laying, and at least 30 days after installation (to allow for settling), the pipe will be tested again for final acceptance. The test shall be performed by the contractor pulling a mandrel of specified dimensions through the pipeline.

This specification covers the requirements of high density polyethylene profile wall gravity sewer and drain pipe fittings in nominal sizes 18" through 96" with integral bell and spigot gasketed and welded joints.

Class selection for high density polyethylene profile wall sewer pipe shall be a minimum of Class 160 for pipe with 0 to 20' of fill. Polyethylene pipe cannot be used over 20' deep.

Pipes and fittings shall be manufactured from high density polyethylene resin compound which shall meet the requirements of Type III, Class C, Category 5, Grade P 34 per ASTM D 1248. Materials meeting the requirements of ASTM D3350 with a cell classification PE 334433C or higher are also suitable. The pipe shall contain a minimum of 2% carbon black as an ultraviolet inhibitor.

The average inside diameter and the minimum wall thickness of the waterway of the pipe shall comply with ASTM F894 for RSC Class 160 pipe.

The pipe shall be produced with bell and spigot end construction. Joining shall be accomplished by use of neoprene rubber gaskets complying with the physical requirements as specified in ASTM F477. Joints shall be in accordance with ASTM D3212 and withstand an internal operating pressure of 50 psi.

The profile wall shall be substantially strong to protect against any diametrical deformation. All polyethylene profile wall pipe shall have a minimum specific pipe stiffness of 46 psi at a deflection of 5% of the internal diameter when tested and calculated in accordance with ASTM D24212 (latest edition).

(a)

If the results of any tests do not meet the requirements of this specification, the tests may be conducted again in accordance with agreement between purchaser and seller.

(b)

In retesting, the product requirements of this specification shall be met and the test methods designated in this specification shall be followed. If upon retest failure occurs, the quantity of product represented by the tests shall be rejected.

(a)

Vertical deflection of installed pipe shall not exceed 7½% of the undeflected diameter as defined in Table X1.1 of ASTM D3034.

(b)

Each segment of line (except service lines) will be tested at the end of each month just prior to submitting for payment on that segment. Upon completion of the pipe laying, and at least 30 days after installation (to allow for settling), the pipe will be tested again for final acceptance. The test shall be performed by the contractor pulling a mandrel of specified dimensions through the pipeline.

The work included in this section and related sections includes furnishing all labor, equipment, and materials required to install, test, and inspect reinforced concrete (ASTM C-76) pipe sewers, including all risers, plugs, fittings, and bedding, as shown on the drawings and/or specified herein.

The contractor must submit to the owner and engineer the concrete pipe manufacturer's evidence of a working quality control program for approval, prior to any pipe being manufactured. The program and standards of manufacturing must be established and well defined. The program must include the minimum following requirements:

(a)

A full time quality control technician.

(b)

A complete and working quality control laboratory capable of testing and recording the requirements set forth in these specifications for concrete pipe.

(c)

Written documentation of the concrete pipe manufacturer's performance on a recent sewer project. The performance results must be from a tested and approved installation of the pipe material set forth in this specification from either the owner and/or engineer stating that the pipe tested and met the requirements.

(d)

A zero defect program for daily material testing and finished product testing to assure quality control as the pipe is being manufactured and shipped for this particular project.

(e)

Provide the services of a competent factory representative of the pipe manufacturer for purposes of supervising and/or inspecting the installation of pipe. This service shall be for the duration of the project.

(f)

Provide equipment and labor to air test each joint of pipe (30" diameter and larger) as it is installed. Joint tester shall be "Cherne Large Diameter Joint Tester" or equal. This testing shall in no way relieve the contractor from the responsibility of performing infiltration/exfiltration tests.

(a)

Concrete gravity pipe (ASTM C-76) used on this project shall meet all materials and testing requirements of ASTM C-76, ASTM C-443, and ASTM C-497 (except where modified herein). Manufacturer shall secure the services of an independent testing laboratory to conduct the tests. Testing laboratory shall be approved by the engineer prior to conducting any tests. All testing costs shall be paid for by the pipe manufacturer.

(b)

Testing shall be in job lots (a Job Lot is a continuous run of one size of pipe for this project) for a maximum of 6% of pipe quantity or a minimum of 5% of pipe quantity. The test specimen will have a minimum of 2 joints for pipe of 16' laying length. For pipe of 12' laying length, the maximum number of joints shall be 7 and the minimum number shall be 2. Bulkheads will be included in this joint count.

(c)

A representative of the Owner will be present to witness all tests that are conducted at the manufacturer's site and shall record all results. Manufacturer shall notify the Engineer at least 48 hours prior to conducting any tests.

(d)

The following test shall be required: Pipe barrels shall be subjected to an internal hydrostatic pressure of 10 psi for 10 minutes. Pipe joints shall be subjected to an internal hydrostatic pressure of 13 psi for 10 minutes. The testing of the joints will be in the straight and deflected alignment. The manufacturer shall conduct 3 external load crushing strength tests per job lot. This test shall be by the 3-edge bearing method. The test may be taken to Ultimate Load. Absorption tests shall be conducted as per ASTM C-497. The absorption rate of the sample from the pipe wall shall not exceed 6%.

(e)

If any test specimen fails to pass any of the above tests, 2 additional test specimens shall be chosen at random from the job lot and tested. If either of those 2 specimens fails the test, then the entire job lot is subject to rejection. If the manufacturer requests further testing, then every section of pipe in the job lot must be tested.

(f)

In addition to the above tests, manufacturer shall conduct tests to determine alkalinity of cover concrete as detailed in this section.

(g)

Each pipe shall be clearly marked as required by the governing ASTM standard specifications to show its class, date of manufacture, and the name of trademark of the manufacturer.

(h)

Any pipe or specials which have been broken, cracked or otherwise damaged before or after delivery or which have failed to meet the required tests, shall be removed from the site of the work and shall not be used therein.

The contractor shall provide a guarantee against defective materials and workmanship.

(a)

All concrete pipe and fittings 12" in diameter and larger shall be reinforced concrete sewer pipe conforming to the latest requirements of ASTM C-76 with the following modifications: All concrete pipe with 0 to 20' of fill shall be a minimum of Class III with 4500 psi concrete. All pipe with 20 to 30' of fill shall be Class IV with 4500 psi concrete. All pipe with 30' of fill and over shall be Class V with 5500 psi concrete.

(b)

Pipe shall have circumferential reinforcement as required for the particular class of pipe furnished. The bell and spigot of the joint shall contain circumferential and longitudinal reinforcement. Reinforced concrete pipe shall be centrifugally cast or vibrated, horizontally or vertically cast or made on a Packerhead machine and shall be furnished in lengths not more than 20' and not less than 8', except where short lengths are required for construction conditions. Reinforced concrete pipe shall have bell and spigot joints suitable for the use of a rubber gasket to be provided as a part of this item.

(c)

Concrete pipe for sanitary sewers shall have bell and spigot joints consisting of self-centering steel joint rings securely attached to the pipe reinforcing steel. The steel joint rings shall be suitable for use with a rubber O-ring type gasket to be provided as part of this item.

(d)

Bell and spigot joints consisting of self-centering steel joint rings shall have the joint rings securely attached to the pipe reinforcing steel. The rings which form the joint shall be made so that they will join with a close, sliding fit. The joint surfaces shall be such that the rubber gasket shall be confined on all sides and shall not support the weight of the pipe. The spigot ring shall have an external groove accurately sized to receive the gasket. Special section steel for spigot rings shall conform to ASTM A-283, Grade A, or ASTM A-306, Grade 50. The bell ring shall be flared to permit gradual deformation of the gasket when the joint is assembled. Minimum thickness of bell rings shall be s (3/16"). Bell rings ¼" or thicker shall conform to ASTM A-283, Grade A, or ASTM A-306, Grade 50. Bells less than ¼" thick shall conform to ASTM A-570, Grade A. Each ring shall be precisely sized by expansion beyond the elastic limit of the steel and then gauged on an accurate template. All exposed surfaces of both rings shall be protected by a corrosion-resistant coating of zinc applied by an approved metallizing process after proper cleaning.

(a)

The coal tar epoxy system shall be Koppers 300 M, Porter Tarset, Wise Chem CTE 200, Amercoat 78, Protecto 101 or equal.

(b)

The interior concrete or mortar surfaces of pipe and fittings are to be sandblasted and painted with one coat of a high-build, coal tar epoxy system or 2 coats of a standard coal tar epoxy system. The dry film thickness of the total system shall be 16 mils minimum on concrete or mortar surfaces and on steel joint ring surfaces.

(c)

Sandblasting shall result in a clean dry surface free of oil, grease, or other contaminants. Any air pockets over ¼ inch in diameter and ⅛" deep appearing on the concrete surface after sandblasting will be filled with an epoxy sand patching material such as those sold by Sherwin-Williams, Glidden, or Moran. The epoxy sand patch should be troweled prior to the application of the coal tar epoxy.

(d)

Any steel surfaces to be painted should be sandblasted, solvent cleaned, or wire brushed prior to painting. Application of the coal tar epoxy shall be by brush, roller, or spray system using equipment recommended by the manufacturer of the coal tar epoxy system. The temperature during application and curing of coal tar epoxy shall be as recommended by the manufacturer of the coal tar epoxy. Time between coats (if applicable) shall be as recommended by the manufacturer of the coal tar epoxy.

(e)

If the inside joint recess will be mortared and painted with coal tar epoxy in the field, the pipe supplier shall not paint the inside vertical surfaces at the ends of the pipe. When the inside joints will not be mortared in the field, the pipe supplier shall paint the inside vertical concrete or mortar surfaces at each end of the pipe.

(f)

The paint shall be extended continuously over the front lip of the steel spigot ring and a minimum of 2" onto the sealing surface of unrestrained bell rings so that all interior joint surfaces which can be exposed to the fluid inside the pipe are coated.

Steel pipe shall meet the requirements of ASTM A-139 Grade B, AWWA C-200-75 and shall be coal tar lined 3/32" in accordance with AWWA C-203-75. The outer coating shall be sand/grit blasted, primed to Federal Specification TTP-86C. Pipe shall have a minimum wall thickness of 0.250".

(a)

Manholes. Precast concrete manholes shall consist of precast reinforced concrete sections with eccentric, (or flat slab for shallow manholes) top section and a base section conforming with the typical manhole details as shown on the Standard Detail Drawings.

(b)

Manhole sections. Precast manhole sections shall be manufactured, tested, and marked in accordance with the latest provisions of ASTM Standard Specifications, Serial Designation C 478.

(c)

Manhole section joints. Joints of the manhole sections shall be of the tongue-and-groove type, sections shall be joined using O-ring rubber gaskets, flexible plastic gaskets conforming to the applicable provisions of ASTM Standard Specification, Serial Designation C 433, latest revision, or an approved bituminous mastic joint material.

(d)

Lift holes. Each section of the precast manhole shall have not more than 2 holes for the purpose of handling and laying. These holes shall be sealed with cement mortar using one part Portland cement to 2 parts clean sand, meeting ASTM Standard Specifications, Serial Designation C 144, latest revision.

(e)

Manhole steps. Manhole steps conforming to the applicable provisions of ASTM Specification C 478, latest edition, shall be of #4 steel reinforcing bars covered with Polypropylene Plastic or rubber and shall be supplied with depth rings and other necessary appurtenances. Steps shall be similar to and of an equal quality to the "PS1-PF" by M. A. Industries, Inc. of Peachtree City, Georgia. The step shall be factory built into the precast sections. See the standard details for a typical manhole step detail.

(f)

Pipe holes. Holes in precast bases to receive sewer pipe shall be precast at the factory at the required locations and heights. Knocking out of holes in the field will not be permitted, however, holes can be cored in the field with a coring machine. All manholes shall have Kor-N-Seal (or equal) rubber boots for all pipe entries/exits.

(g)

Bases and inverts. Manhole bases and inverts shall be constructed of 2,500 psi concrete in accordance with details on Standard Detail Drawings and the trough shall have the same cross-section as the sewers which it connects. The manhole base and invert shall be carefully formed to the required size and grade by gradual and even changes in sections. Changes in direction of flow through the sewer shall be made to a true curve with as large a radius as the size of the manhole will permit. The minimum drop through a manhole shall be 0.1 foot.

(h)

Manhole foundation. The manhole base shall be set upon a 6" (minimum thickness) mat of #57 crushed stone.

(i)

Brick. Brickwork required to complete the precast concrete manhole shall be constructed using one part Portland cement to 2 parts clean sand, meeting ASTM Specifications, Serial Designation C 144, thoroughly mixed to a workable plastic mixture. Brickwork shall be constructed in a neat and workmanlike manner. Cement mortar shall be used to grout interior exposed brick joints and faces. No more than 3 courses of brick with 9" maximum total depth of bricks may be used to adjust manhole covers.

(j)

Frame and cover. The cast iron frame for the manhole cover shall be set at the required elevation and properly anchored to the masonry. Frames and covers shall be Neenah R-1776 or equal in compliance with the latest edition of ASTM 48. Where manholes are constructed in paved areas, the top surface of the frame and cover shall be tilted, if necessary, to conform to the exact slope, crown and grade of the existing adjacent pavement. In areas where manhole tops may be submerged by street runoff or high flood waters, the manhole lid shall be "self-sealing." All covers shall have sewer printed on them.

(k)

Masonry work. Masonry work shall be allowed to set for a period of not less than 24 hours. All loose or waste material shall be removed from the interior of the manhole. The manhole cover then shall be placed and the surface in the vicinity of the work cleaned off and left in a neat and orderly condition.

(l)

Location. Manholes shall be installed at the end of each line; all changes in grade, size, or alignment; at all intersections; and at distances normally not greater than 350'. Spacings for 8" sewers can be more than 350' but not more than 400' and will be allowed only in isolated cases when, in the opinion of the reviewing engineer, it is impractical to install an additional manhole and when the extra distance will not impede maintenance of the line. Manhole spacing in sewers 10" and larger will conform to Ten State Standards. In no circumstance will a spacing of greater than 300' be allowed when the slope exceeds 10%. Cleanouts may be used only for special conditions and shall not be substituted for manholes nor installed at the ends of laterals greater than 150' in length. Manholes in cross-country areas shall be elevated so that the top is 18" above ground.

(m)

Drop manholes. A drop pipe shall be provided for a sewer entering a manhole at an elevation of more than 2' above the manhole invert. The drop pipe shall be of ductile iron materials. All outside 90 degree elbows shall have thrust block poured below the elbow. Outside Drop Manhole will be noted on the construction plans at any time the drop exceeds 2'. Where the difference in elevation between the incoming sewer and the manhole invert is less than 2', the invert shall be sloped to prevent solids deposition.

(a)

Steel casing pipe shall be used for all cased piping where the carrier pipe is 8" or greater in size.

(b)

Steel casing pipe shall have a minimum yield strength of 35,000 psi and shall conform to the requirements of ASTM A139. It shall be fully coated on the exterior and interior with a coal tar coating. The casing pipe diameter shall be 6" to 8" greater than the "bell" diameter of the carrier pipe. Minimum wall thickness shall be as shown on the following table:

Thickness of Steel Sewer Pipe Wall

Wastewater treatment facilities must comply with all rules contained in the "Rules and Regulations for Water Quality Control" of the Georgia Department of Natural Resources, Chapter 391-3-6 latest edition, as amended from time to time.

The public works director of the City of Powder Springs shall have the right to review and modify facility designs if these modifications are in the interest of the city.

The public works director and/or his designated representative of the City of Powder Springs shall have the right to review and inspect all construction and may reject any work that does not meet quality control standards.

After completion of construction, the city will provisionally accept the project for operation subject to the requirements for maintenance as provided in these specifications.

The developer shall submit 6 copies of an approved operations and maintenance manual for the facility to the City of Powder Springs.

The developer shall post a maintenance bond on the facility for a 2 year period after completion and acceptance of the facility by the City of Powder Springs. In addition the developer shall post a payment bond on the facility for all subcontractor and material supplier work.

It shall be the developer's obligation to provide all maintenance for a 2 year period after acceptance of the project by the City of Powder Springs. At the end of the 2 year maintenance period the public works director and/or his designated representative of the city shall inspect the facility, and upon correction by the developer of all deficiencies noted by the public works director and/or his designated representative, the city will accept the facility for operation.

If a developer wishes the city to consider allowing the relocation of an existing wastewater treatment facility the following shall apply:

(a)

All of the rules outlined in other sections of this division shall apply.

(b)

The city or its consultant will inspect the facility that is proposed to be relocated and prepare a deficiency list, which must be corrected by the developer prior to acceptance of the facility by the city.

(c)

All of the cost incurred by the city for the consultant's time will be borne by the developer as will the cost of correcting deficiencies noted per this section.

All reports, plans and studies submitted to the city by the developer must carry the seal of a Professional Engineer competent in the design of sewerage treatment works in the State of Georgia.

(a)

Flooding. Lift stations shall remain fully operational and accessible during the 25-year flood. All electrical controls shall be above the 100-year flood level. All motors and mechanical equipment shall be protected against physical damage from the 100-year flood.

(b)

Access road. Access roads shall be paved with a 12' wide surface of either concrete (4" thick with wire mesh) or asphalt (6" Graded Aggregate Base, plus 2" Type E asphalt). Maximum grade shall be 20%.

(c)

Fencing. Lift station sites shall be fenced with a minimum of 6' high chain link fencing topped with 3 strands of barbed wire. Access gates shall be a minimum of 15' in width. A paved area inside the fencing shall be provided to facilitate service vehicle access to the pumping station wet well and other facilities. A paved turn around area shall be provided whenever the access road length exceeds 200' or when the road grade exceeds 10%.

(d)

Screening. Where natural screening is not present to screen the site from view of residences, special plantings shall be installed to screen the site.

(e)

Ground covers. All ground areas inside the fence and extending 4' beyond the fence shall be treated with a herbicide and covered with a geotextile fabric, followed with a 4" thick layer of #57 stone. The geotextile fabric shall be a nonwoven polypropylene weighing 8 oz./S.Y. with a minimum burst strength of 250 psi, such as Amoco Type 4553 or equal.

(f)

Water supply. A metered water supply line (¾ inch minimum size) shall be installed to the site, and a freeze-proof yard hydrant located near the wet well. The hydrant shall be equipped with a suitable backflow preventer (Watts No. NF8 or approved equal).

(g)

Lighting. One pole-mounted, photo cell controlled, watt mercury vapor security light shall be installed. It shall be equipped with a manual on/off switch (located in the main control panel) to override the photocell control.

(h)

Ownership. Both the lift station site and the access road right-of-way shall have ownership dedicated to the city, and this shall be indicated on the subdivision plat or development plan. The dedicated space for the lift station shall include sufficient space for parking of 2 trucks, plus turn-around, plus slope maintenance. The dedicated width on road right-of-way shall be 30' minimum.

(a)

Lift stations having less than 500 gpm capacity (per pump) shall utilize 2 submersible centrifugal pumps each having a capacity equal to the design flow.

(b)

Lift stations having a capacity of 500 gpm or more shall be reviewed on an individual basis and may have requirements differing from those outlined in this division.

(c)

Grinder type centrifugal pumps will be used for pumps of less than 100 gpm. Force mains shall be sized to provide a velocity of at least 2½' per second.

(d)

The design shall allow for easy removal of any pump or equipment item without the need to shutdown the entire lift station.

(e)

Manufacturers meeting approved standards include Flygt, Aurora, and Myers. Others meeting these standards may be approved. The city reserves the right to review each application on an individual basis.

(f)

Lift stations with pumps up to 15 hp shall be supplied with a spare complete pump. Lift stations with pumps above 15 hp shall be supplied with an extra impeller and set of bearings plus a complete set of manufacturer's recommended spare parts.

Pumps shall have the following features:

(a)

Non-clog impeller.

(b)

Be capable of passing a 3" sphere (except grinder pumps).

(c)

Be capable of running without being submersed.

(d)

Have dual mechanical seals with seal leak indicator light in the control panel.

(e)

Pump and motor casings shall be cast iron, and all fasteners shall be stainless steel.

(f)

Motor shall be selected to be non-overloading under all operating conditions.

(g)

Motor winding shall have a heat sensor with auto reset to prevent overheating; 3-phase motors shall have 2 sensors.

(h)

Operating speed of the pump shall not exceed 1,800 rpm without special approval.

(i)

Motor shall have upper and lower roller bearings.

(j)

The pump shall be automatically connected to the discharge connection elbow when lowered into place, and shall be easily removed for inspection or service. There shall be no need for personnel to enter pump well. Sealing of the pumping unit to the discharge connection elbow shall be accomplished by a simple linear downward motion of the pump. Each pump shall be equipped with a chain (of aluminum or other non-corrosive material) for easy removal.

(a)

Wet well volume. The wet well volume shall be sized to limit pump cycles to no more than 6 cycles per hour under worst conditions.

(b)

Ventilation. For wet wells, the minimum requirement shall be 2 gravity vent pipes designed for natural ventilation. Where conditions are conducive to formation of hazardous conditions (in the design engineer's opinion) then mechanical ventilation shall be provided. For dry wells, mechanical ventilation shall be required.

(c)

Submersible lift stations. Submersible lift stations shall have a wet well structure and a separate valve pit. Both structures shall be precast concrete with a monolithic base. The valve pit shall be 4' by 4' by 5' deep with manhole steps, floor drain pipe, and a 3' by 3' aluminum access hatch. Wet wells may be either round or rectangular and shall have a diameter or width of at least 4'. Wet wells shall be sized to meet cycle time requirements with a drawdown (i.e., the distance between high water level and low water level) of not more than 3'. The wet well shall have an aluminum hatch large enough for easy removal of pumps.

(d)

Riser sections. Riser sections in precast units shall be sealed watertight using butyl rubber sealant or other approved sealant. Mastic shall not be used. Structures shall be adequately reinforced for all loading conditions normally encountered during shipping, construction and service. All openings (for pipes, hatch, conduits) shall be either cast in place or neatly cut. Sewer pipe connections shall utilize rubber boot connectors, and be watertight. The wet well shall be equipped with an aluminum ladder.

(e)

Accessories. All materials inside the wet well and valve pit shall be corrosion resistant. Mechanical equipment requiring ferrous metals shall have a coal tar epoxy coating. Guide rails for pumps shall be stainless steel. Miscellaneous metals including fasteners shall be aluminum or stainless steel; anchor bolts shall be stainless steel.

(f)

Pressure gauge. A pressure gage shall be installed on the force main downstream of the gate valves, inside the valve pit and visible from ground level. A corporation stop shall be installed on the tap to allow removal of the gauge.

(g)

Valves. The discharge pipe of each pump shall have a check valve followed by a gate valve before the 2 pipes join into a common force main.

(a)

The force main shall be sized for a minimum velocity of 2½' per second with one pump operating.

(b)

Force mains of 4" diameter or larger shall be ductile iron pipe. Smaller force mains may be used only with grinder pumps and shall be PVC pipe, SDR-21 with gasket joints. PVC pipe shall not be exposed to sunlight or freezing temperatures. Buried PVC pipe shall be marked continuously with metallized locator tape.

(c)

The force main profile shall slope continuously upward where practical. If high points occur where air could be trapped in the pipe, then an air release valve (of the type made for sewage applications) will be installed (in a manhole) at the high points.

(a)

Lift station controls and electrical components shall be factory-wired in completely weather proof stainless steel metal cabinets (NEMA 4X stainless steel). The cabinet shall be provided with condensate heaters and spare fuses of each type that is used in the electrical/control system.

(b)

A main circuit breaker shall be installed to disconnect power to the entire station.

(c)

Three phase power will be provided for all motors exceeding 5 hp. Phase converters will not be allowed.

(d)

Protection against voltage surge and loss of a phase shall be provided.

(e)

The factory-wired panel shall be equipped with a ground bus and neutral bus. Terminal shall be suitable for either aluminum or copper wire. All internal panel wiring shall be copper.

(f)

Motors shall be suitable for either 230 volt or 460 volt operation.

(g)

Wet well level shall be controlled by 4 sealed mercury tube float switches. All floats shall be provided with 25' of Type SJO flexible cord and shall be attached to a bracket mounted at the top of the wet well.

The pump control system shall include the following features:

(a)

Lead pump/lag pump alternator.

(b)

Alarm light and horn to indicate high water level.

(c)

Seal failure indicating light.

(d)

Pump failure indicating light.

(e)

Condensate heater.

(f)

Lead pump selector switch.

(g)

H-O-A switch and run light for each pump.

(h)

Control voltage shall be 120v. Wiring shall be neatly tied and number coded to facilitate maintenance. A schematic diagram shall be furnished with the panel.

(i)

120v GFCI-type receptacle.

The need for providing a permanent in-place generator will be determined on the basis of storage time in the sewers leading to the pump station. If the storage time is less than 12 hours then a permanent standby generator must be installed. If storage time equals 12 hours or more only a transfer switch and provisions for connecting to a portable generator will be required. Where required, emergency power will be supplied by an on-site emergency generator. The generator shall be diesel powered with an automatic transfer switch and provisions for an automatic exercise cycle. Specifications for the generator shall be provided by the city.

The following rules shall apply:

(a)

Storage volume available shall be taken as the volume between the low water level in the wet well and the elevation at which overflow would first occur (this might be the top of the wet well or that upstream manhole having the lowest top elevation). Volume of the wet well, manholes and sewer mains will be counted.

(b)

The rate of sewage inflow for these computations shall be taken as 150 gallons per day per residential unit. Systems serving other than residential customers will be considered individually.

(c)

Height of manholes shall not be extended above normal for the purpose of meeting this rule. The design shall ensure overflow before backing sewage into a dwelling or other building.

The minimum requirement for standby power for lift stations shall be that each station that does not have a permanent in-place generator shall have installed a manual transfer switch and receptacle for quick connection of a portable generator.

Submittal of construction plans shall include the following lift station information:

(a)

Capacity calculations. Use one gpm capacity per house on residential developments of less than 200, except that the minimum pump capacity shall be 30 gpm.

(b)

System head calculations; tabulated and plotted on the pump curve. Include a plot of force main velocity.

(c)

Standard drawings, details and specifications sufficient to ascertain compliance with the requirements of this division.

(d)

Calculations showing determination of wet well volume and cycle time at design conditions.

(e)

Calculations showing volume of storage available in the event of a power outage. The storage zone shall be delineated on plan and profile drawings of the sewer system.

(f)

Buoyancy computations showing that structures are protected against flotation.

After construction plan approval but before purchasing any lift station equipment, shop drawings shall be submitted including the following information:

(a)

As-built drawings shall be furnished including one set of mylar sepias plus 4 sets of prints Manufacturer's catalog sheets, performance curves, installation drawings, specifications and list of options for the specific pump that is offered for approval.

(b)

Catalog data for controls, valves, hatches, yard hydrants, precast wet well and other manufactured items.

(a)

After installation and before placing the system into full operation, the work must be inspected by the developer's engineer who must then issue a certification to the city verifying that all work has been done in accordance with approved plans.

(b)

After acceptance of the work by the engineer, a factory representative shall inspect and start up the system certifying rotation, capacity; amperage draw, lack of vibration and other standard check points.

(c)

This certification shall state the beginning date of the warranty and include a copy of the warranty.

On or before the date of start-up, 5 sets of factory operations and maintenance manuals shall be delivered to the city. These shall include the name of the contractor (or whoever's name the purchase was under), the serial numbers of pumps, telephone number and address for purchase of parts and detailed wiring schematics.

Regardless of the manufacturer's warranty terms, the developer will be responsible for all repairs necessary within one year from the date the station is completed and approved by the city. The developer will be required to furnish such assurances to the city as deemed appropriate by the city to ensure prompt action.