A. Purpose
1. The purpose of this Section 5.4 is to establish the minimum acceptable standards for improvement of public streets and utilities, to define the responsibility of the subdivider in the planning, constructing, and financing of public improvements and to establish procedures for review and approval of engineering plans.
2. All improvements required in streets or easements that are required as a condition to plat approval shall be the responsibility of the subdivider.
3. Any subdivider failing to comply with the following minimum acceptable standards shall be punished as provided in these Subdivision Regulations.
B. Engineering Plans
1. Except for specific exemptions relating to rural subdivisions as set forth in these Subdivision Regulations, the subdivider shall have a complete set of engineering plans and specifications prepared by a registered civil engineer who is currently registered in the State of Arizona, and submit such plans to the Public Works Department for approval. Such plans and specifications shall be based on the approved preliminary plat and shall be prepared in conjunction with the comprehensive development plan, or if no comprehensive development plan is required, prepared and submitted in conjunction with the final plat review process.
2. Final engineering plans shall be approved by the Public Works Director prior to recordation of the final plat. This final plan approval is valid for a period of one (1) year. If construction is not started prior to the plan approval expiration, the plans shall be resubmitted to the Public Works Department for an update approval according to then-current standards and guidelines. If, after construction has begun on a project and it is stopped for any reason for a period of one year or more, the plans must be resubmitted for update approval prior to restarting construction. The plans will be reviewed for compliance with then-current standards and requirements.
3. Improvement plans shall include plans, profiles and typical street cross sections that contain the following minimum information:
a. The cover sheet shall include at least the following information:
(1) Name and type of plan.
(2) Vicinity map.
(3) Location map.
(4) Benchmarks approved by the Town.
(5) Basis of bearing for the project.
(6) Name, address, and phone number of subdivider.
(7) Name, address, phone number, and professional seal of engineer preparing plans.
(8) List of utility agencies serving the proposed development.
(9) Plan sheet index.
(10) Approval signature block of the Town officials, including the Public Works Director.
(11) Bluestake note.
b. Plans shall include at least the following information:
(1) Street names.
(2) A north arrow and graphic on each plan sheet.
(3) Stationing and lateral dimensions of streets and rights-of-way, including pertinent survey data and curb return data.
(4) Location of existing and proposed utilities being designed and existing streets to be joined.
(5) Drainage structures, including cross gutters, culverts, catch basins, or similar items. Show a positive outlet for all drainage leaving the site sufficient to ensure will not have a negative impact on the downstream property. All concentrated drainage flowing from public right-of-way onto private property must have a drainage easement to flow into or a note on the final plat relating the drainage impact on the lot.
(6) Curb, gutter, sidewalks and asphalt structures.
(7) Survey monument location to be set, existing control monuments to be referenced prior to destruction and all benchmarks used.
(8) New traffic control devices, all existing traffic control devices within the area of the project, and changes in traffic control devices in the vicinity of the project that are required as a result of the project.
(9) The top and toe of slopes for both cuts and fills shall be shown if the project extends outside of the right-of-way limits.
(10) Location of all existing and proposed water lines, water valves, water meters, water service lines, fire hydrants, sewer manholes, sewer services, storm drains, and street lights shall be shown on the plans.
(11) Construction notes indicating any and all construction items for utilities, paving, storm drainage, etc.
(12) Town current general notes for construction.
(13) A plan sheet showing the location of all traffic control signs shall be included as a plan sheet.
(14) Additional information needed to clarify plans or deal with specific conditions.
c. Profiles shall include at least the following information:
(1) Bench marks, including description, location and elevation;
(2) Existing and finished grade profiles. Profiles of centerline and right and left gutter control line or edge of pavement are required. The presentation must clearly show and distinguish existing profiles and other profile information;
(3) Finished elevations including BVC, PI, and EVC of vertical curves, vertical intersection points, curb returns match lines and all other points needed for vertical control of construction.
(4) Slopes and vertical curve lengths.
(5) Curb return profiles at intersections.
(6) Drainage structures and utilities.
(7) Extension of the improvement project as required to ensure that the design is compatible with future extensions.
(8) Consistent stationing throughout the plans.
(9) Additional information needed to clarify profiles or deal with special conditions, including, but not limited to, profile or drainage channels, stationing and elevations at beginning and end of all curb returns, grade breaks and beginning and end of construction.
d. Cross Sections shall include at least the following:
(1) Typical street cross-sections are needed for each condition encountered and each should be clearly identified as to where it applies.
(2) Materials and thickness, including sub-base select material aggregate base, prime coat, asphaltic concrete, curb and gutter, and sidewalk with notation of the engineering firm preparing the soils reports and the report numbers, if applicable. The specification and types of materials shall be stated.
(3) Horizontal dimensions to all key points, including rights-of-way.
(4) Cross slopes.
(5) Parkway conditions. Maximum and minimum slopes are to be shown for cuts, fills, and side hill conditions. Any side ditches or other special conditions are to be shown. A minimum two (2)-foot wide flat area shall be constructed behind the sidewalk or curb before the slope begins.
(6) Right-of-way widths in relation to centerline, and identified by street name to which it is applicable;
(7) Limits of applicability by station if necessary.
e. The plans shall contain the current Town “General Notes” for water, sewer, grading, and paving construction as prepared by the Public Works Director.
f. One set of Record Drawings on reproducible film and electronic file (AutoCAD or approved equal) of all improvements must be submitted to and approved by the Public Works Director prior to final approval of the project.
C. Construction and Inspection
1. All improvements in the public rights-of-way and easement s shall be constructed under the inspection and approval of the Town. The subdivider shall be responsible for the total cost of all inspection and testing during the construction of all improvements. The subdivider will execute an Infrastructure Improvement Agreement (IIA) with the Town and the subdivider will be responsible for the performance of the required inspections and testing. If the IIA provides that the Town will perform the inspection and testing, an estimated advance payment will be provided to the Town prior to the commencement of any construction work. If the IIA provides that the subdivider will be responsible for providing qualified engineers to conduct inspection and testing, a payment in the amount as established by resolution, will be required for the Town's oversight and monitoring of the IIA requirements.
2. All construction work shall be performed and all material furnished shall be in reasonably close conformity to the lines, grades, cross sections, dimensions, and material requirements, including tolerances shown on the plans and profiles or indicated in the specifications. The Public Works Director shall determine the limits of reasonably close conformity in each individual case and the Public Works Director's judgment shall be final and conclusive.
3. The Public Works Director shall be notified at least three (3) calendar days before the start of any construction. Clearing and grubbing activities shall not proceed without approved Improvement Plans by the Public Works Director.
4. All relocation and reconstruction of irrigation and utility facilities shall be conducted to the standards of the owning utility and the Town.
5. All underground utilities installed in streets shall be constructed prior to the surfacing of such street. Service stubs for underground utilities to platted lots within the subdivision shall be placed to such length as not to necessitate disturbance of street improvements when service connections are made.
6. Prior to the Town accepting any subdivision, the subdivider shall submit engineering record drawings or as-built plans for all water and sewer infrastructure.
The record information shall be submitted on both a high quality mylar having a thickness of approximately four (4) mil and in a digital format that is compatible with the Town computer database to facilitate the inclusion of the plans into the Town database. Typically, the form of these files will be in DXF, DWG or other similar industry standards digital file developed in a recent version of AutoCAD according to the Town’s technological capabilities. Additionally, a certified letter from a professional land surveyor shall be required, stating that the centerlines of streets, easements, and survey monuments are located as denoted on the final plat.
7. When public infrastructure improvements for a subdivision are accepted by Council for maintenance and operation, the developer shall provide all approvals from all appropriate regulatory agencies (for example, ADEQ Approval of Construction) and shall provide a warranty or guarantee for a period of two (2) years against defective materials and workmanship.
D. Development of Plans and Specifications
The “Uniform Standard Specifications and Details for Public Works Construction” as published by the Maricopa Association of Governments (MAG) are recognized as acceptable construction specifications and standard details. Because of variations in climate, soils, and availability of materials, modifications to the MAG specifications may have been implemented by the Town. The MAG specifications shall be utilized at the direction and approval of the Public Works Director. Other pertinent manuals for the development of plans and specifications include “A Policy on Geometric Design of Highways and Streets” as distributed by AASHTO; all design manuals, specifications, and standard details as distributed by the Arizona Department of Transportation; all engineering bulletins as distributed by the Arizona Department of Environmental Quality; “Manual on Uniform Traffic Control Devices for Streets and Highways” as distributed by the U.S. Department of Transportation, Federal Highway Administration; and the various design manuals, procedures, and guidelines as published by professional organizations and governmental agencies.
E. Streets
1. Except as specifically exempted for rural streets as set forth in these Subdivision Regulations, a geotechnical report shall be required for the pavement design of all subdivision streets. The design approach shall be based on the latest methodology that is utilized by the Arizona Department of Transportation or the American Association of Highway and Transportation Officials.
Traffic volumes for the pavement design shall be based on a trip generation analysis as developed by the Institute of Transportation Engineers.
2. Portland cement concrete shall normally be used for all required curb and gutter, valley gutters, and sidewalks unless otherwise approved by the Public Works Director.
3. A seal coat shall be required on all street paving projects. If pavement cuts occur after the final lift of asphaltic concrete then a chip seal will be required.
4. The developer shall be responsible for the installation of all regulatory, warning, and street signs for the orderly movement of vehicles and for public safety. Regulatory and warning signs shall be in conformance Manual on Uniform Traffic Control Devices. Street signs shall be in accordance with Town standards and include 911 or emergency addressing.
F. Drainage
1. Subdivider must show the limits of the one hundred (100)-year floodplain on the final plat in a readily retraceable manner with frequent ties to intersecting lot lines for all flows of fifty (50) cubic feet per second or more.
2. Watercourses that are relocated, altered, or include any man-made improvements, should be developed with channel treatments that allow for the reestablishment of vegetation. The use of concrete will be limited to headwalls, cut-off walls, transitions, and areas with limited right-of-way because of existing improvements. The placement of concrete structures shall be at the discretion of the Public Works Director.
3. Culverts for streets shall be designed to convey at the fifty (50)-year peak discharge with no flow over the roadway. Additionally, the flow depth over the street shall be limited to one (1.0) foot for one hundred (100)-year peak discharge if the street provides all weather access.
4. A minimum pipe diameter of eighteen (18) inches is required for all street crossings and a minimum pipe diameter of twelve (12) inches is required for all driveways.
5. Culvert outlet velocities should be kept below fifteen (15) feet per second unless approved by the Public Works Director due to special conditions. The maximum velocity should be consistent with the channel stability requirements at the culvert outlet. If the culvert velocities exceed permissible velocities for the proposed outlet (greater than five (5) feet per second for natural conditions depending on soil types), suitable outlet protection must be provided.
6. Drainage ditches or storm drains along streets and adjacent areas shall be required to avoid trapping water and to ensure positive drainage away from the streets. Street drainage shall be designed to provide for one (1) lane of traffic on all local streets and one (1) lane of traffic in both directions for all collectors and arterials for the ten (10)-year peak discharge.
G. Water
1. New water facilities shall be designed in accordance with the Arizona Department of Environmental Quality (ADEQ) and the Arizona Department of Health Services Bulletin No. 10 (latest edition). Any deviation from the bulletin's requirements shall have the written approval of the Public Works Director.
2. All water mains shall be a minimum of six (6) inches in diameter, unless designated otherwise by the Public Works Director, to ensure minimum water flow requirements of the pressure zone or the Chino Valley Comprehensive Water Master Plan.
3. All water mains, valves, and fittings shall be constructed with materials having a working pressure rating of two hundred (200) pounds per square inch.
4. The longitudinal bending of water mains shall not be allowed. All changes in direction or angle will require the appropriate fittings.
5. All dead ends on new mains shall be provided with a blow-off cock in the plug or cap, and reaction backing or thrust blocking shall be arranged not encased or covered by the concrete, if used.
6. Fire hydrants shall be spaced at a distance no greater than five hundred (500) feet apart in residential areas and five hundred (500) feet apart in commercial and industrial areas. The measurement between fire hydrants shall be linear and the measurement will be effected along the centerline of the streets. The Chino Valley Fire District may adjust the distances between fire hydrants when circumstances dictate.
7. The water system for the subdivision must be capable of supplying and sustaining the required flows for fire protection throughout all subdivided properties as approved by the Town. For residential areas, the minimum required fire flow capability is one thousand (1,000) gallons per minute for a duration of two (2) hours with a minimum system pressure of twenty (20) pounds per square inch while the required fire hydrant flow rate is being met. For all multi-family, industrial and commercial areas, the Chief Building Code Official, in consultation with the Chino Valley Fire District, shall determine minimum fire flow capability and that flow will be provided with a minimum system pressure of twenty (20) pounds per square inch.
8. The approval of the final design of the water system rests with the Council and will be based on the conformity of the design to policy, standards, and specifications. The subdivider is responsible for all approvals with ADEQ and other regulatory agencies.
9. The Town may issue building permits after the approval of the water system and the installation of an all-weather road. Approval of the water system requires that the water lines have been successfully pressure tested and disinfected to Town standards and that fire flow can be provided to all subdivided properties. An all-weather road for this purpose means that the sub-grade and aggregate base material has been constructed to the approved plans and specifications and the width of the road is a minimum of twenty (20) feet wide. Water service shall not be connected to any structures until approval from ADEQ is received.
10. The Town will not issue any certificates of occupancy until the subdivision improvements are accepted for maintenance and operation by Council.
H. Sewer
1. New sanitary sewerage facilities shall be designed in accordance with the Arizona Department of Environmental Quality (ADEQ) and the Arizona Department of Health Services Bulletin No. 11 (latest edition). Any deviations from the bulletins requirements must have the written approval of the Public Works Director.
2. New sanitary sewers shall be designed to carry the designated peak wet weather flow from the area that will be ultimately tributary to the respective reach of sewer.
3. No public gravity sewer lines shall be less than eight (8) inches in diameter. All gravity sewer line pipes shall be of bell and spigot and gasketed joints.
4. The longitudinal bending of PVC SDR 35 sewer pipe is allowable with a minimum allowable radius of one hundred-fifty (150) feet and no joint deflection. Because longitudinal bending is allowable for PVC sewer pipe, drop manholes shall be discouraged with elevational differences addressed by vertical sweeps of the sewer main.
5. Testing of gravity sewer lines and manholes may include multiple test methods to ensure a minimum of inflow and infiltration. Sewer lines shall be subject to but not limited to low pressure air testing, deflection testing, and closed circuit TV inspection. Manholes, at a minimum, shall be vacuum tested after the frame and cover are installed.
6. Low pressure pipe shall be PVC SDR 21 with gasketed joints or HDPE SDR 11 with welded joints. Substitution may be provided if the pipe is of equal or better quality.
7. Low pressure sewer system shall be pressure tested in accordance with applicable test procedures for potable water lines.
8. The outfall for all low-pressure sewer systems shall include adequate measures to prevent sulfide corrosion of manholes and to mitigate odors.
9. Pump stations that are to be operated and maintained by the Town shall be designed as a wet/dry well type system and include odor control, corrosion mitigation measures, and supervisory/control and data acquisition systems.
10. Sewer house service connections shall have adequate separation or protection from potable water house service connections. Sewer service lines should be installed at points ten (10) feet from the lowest lot corner adjacent to the sewer main. Crossing of water and sewer service lines, especially a low-pressure sewer with water service line, may require that the sewer service line be sleeved.
11. The Town will not issue any certificates of occupancy until the subdivision improvements are accepted for maintenance and operation by Council.