[CC 2001 §16.24.010; Ord. No. Z-3-90F §1, 9-11-1997; Attachment §405.060(A — C), 9-11-1997]
Receipt of the signed copy of the preliminary plan is authorization for the subdivider to proceed with the preparation of the plans and specifications for the following minimum improvements and with the preparations of the final plat. Prior to the construction of any improvements required or to the submission of a bond in lieu thereof or to the provision for any assessment for such construction, the subdivider shall furnish all plans, information and data necessary to determine the character of the improvements to an Administrative Officer designated by the City Council. These plans shall be examined by the Administrative Officer and will be approved, if in accordance with the requirements of this Chapter. Following this approval, construction can be started or the amount of a bond determined or an assessment provided for.
No final or official plat of any subdivision shall be approved unless:
The subdivider agrees with the City Council upon an assessment whereby the City is put in an assured position to install the improvements listed below at the cost of the owners of property within the subdivision;
The improvements listed below have been installed prior to such approval; or
The owner of a tract may prepare and secure approval of a preliminary subdivision plan of an entire area and may install the above improvements only in a portion of such area, but the improvements must be installed in any portion of the area for which a final plat is approved for recording; provided however, that trunk sewers and any sewage treatment plants shall be designed and built in such a manner that they can easily be expanded or extended to serve the entire area.
[CC 2001 §16.24.020; Ord. No. Z-3-90F §1, 9-11-1997; Attachment §405.060(D), 9-11-1997]
Street plans, profiles and specifications shall be prepared by a registered professional engineer and approved by the Administrative Officer, Planning and Zoning Commission and City Council.
All streets and public ways shall be graded to their full width, including side slopes and to the appropriate grade and shall be improved by construction of an approved surface in units of one (1) block or more for streets entirely within the subdivision but may include fractional blocks ending at the subdivision boundaries. Such construction shall be subject to inspection and approval by the Administrative Officer designated by the City Council.
Paved streets, with curbs and gutters, shall be surfaced to the following minimum widths, as measured from inside curb lip to inside curb lip: arterial (two lane), forty-four (44) feet; collector, forty (40) feet; sub-collector, thirty-six (36) feet; local, thirty-two (32) feet; marginal access, twenty-four (24) feet. Alleys, within a business district, shall be surfaced to a minimum of sixteen (16) feet. Cul-de-sac turnarounds shall be paved within ten (10) feet of the right-of-way. In instances where parking will be restricted, the above dimensions can be varied with prior approval of the Planning and Zoning Commission and the City Council.
Street surfacing or pavement type shall be restricted to the following two (2) types and shall be constructed in accordance with design characteristics at least equal to those set forth in Article V "Design Standards" of this Chapter.
Prior to the placement of street or alley pavements, adequate surface and subsurface (if required) drainage facilities shall be installed by the subdivider. Pipe used for drainage purposes shall be of corrugated metal, bituminous coated corrugated metal, reinforced concrete or extra-strength vitrified clay of an approved design, size and strength to meet the requirements of the specified conditions which may be encountered. Minimum diameters of pipe to be used shall be as follows:
All construction shall be completed in accordance with the specific conditions in the agreement for street improvements within the improvement plans and in a manner acceptable to the authorities having jurisdiction.
When changes from the accepted plans and specifications become necessary during construction, written approval from the authorities having jurisdiction shall be secured prior to the execution of the changes.
Adequate provision for the maintenance of all street improvements shall be made by dedication to and acceptance for maintenance by the local authorities having jurisdiction or by other suitable means.
Curbs And Gutters.
Curbs and gutters shall be made of Portland cement concrete containing five and one-half (5½) bags of cement per cubic yard of concrete and shall have three percent (3%) to five percent (5%) entrained air.
Curb construction for concrete pavements may be integral. Roll type curbs may be permitted where approved by the Planning and Zoning Commission and City Council.
In accordance with Section 71.365, RSMo., when sidewalks are to be provided, curbs shall be constructed (ramped) so as to enable persons using wheelchairs to travel freely and without assistance. All new curbs and any existing curbs which are a part of a reconstruction project shall comply with these requirements.
At each crosswalk a ramp shall be built into the curb so that the sidewalk and street blend to a common level. Such ramps shall be not less than thirty-six (36) inches wide and shall not have a slope greater than one (1) inch rise per twelve (12) inches length (eight and three-tenths percent (8.3%)). For all ramps there shall be a gradual rounding at the bottom of the slope.
An exception may be granted where, because of surrounding buildings or other restrictions, it is impossible to conform the slope of the ramp with these requirements. In this event, the ramp shall contain a slope with as shallow a raise as possible, but not to exceed ten percent (10%).
Driveway ramps shall not extend past the vertical face of the curb; and ramps shall be built into the curb so that the ramp and street blend to a common level. For all ramps there shall be a gradual rounding at the bottom of the slope.
In the event of development of existing roadways with curbing, the developer shall submit, as a part of the preliminary plan, a curb cutting request for all proposed driveway ramps which shall be subject to approval by the Administrative Officer, Planning and Zoning Commission and City Council.
All plans for the installation of curbs and gutters shall be subject to approval by the Administrative Officer, Planning and Zoning Commission and City Council.
Sidewalks shall be constructed along at least one (1) side of every minor street shown on the plat in accordance with applicable standard specifications of the City and sidewalks shall be constructed along both sides of all major streets; provided however, that where the property is platted in lots having an area of at least twenty thousand (20,000) square feet and width of at least one hundred (100) feet, the City Council may waive this requirement.
When constructed, sidewalks shall be of Portland cement concrete four (4) inches thick, six (6) inches across driveways, with a minimum width of four (4) feet. "Dummy" control joints shall be placed every five (5) feet and expansion joints shall be placed every forty (40) feet. Concrete shall contain five and one-half (5½) sacks of cement per cubic yard and shall have three percent (3%) to five percent (5%) entrained air. Finish shall be by wood float or broom with all edges and joints tooled. The location of sidewalks shall be as shown in Article V "Design Standards".
The subdivider shall provide for the disposal of sewage within the subdivision in accordance with applicable regulations of the City regarding the use of public and private sewers within the City or any future ordinances which may supersede those now in effect. Where a public sanitary sewer main is reasonably accessible, the subdivider shall provide the subdivision with a complete sanitary sewer system, including the lateral connection for each lot, connected to the sewer main. All necessary construction requirements, such as sewer mains and lift stations, shall be the responsibility of the subdivider and approved by the Administrative Officer, Planning and Zoning Commission and City Council and shall comply with the regulations of the Missouri Department of Natural Resources.
Where no sanitary sewer system is accessible and no plans for a sewer system have been prepared and approved, the developer may, upon approval by the Missouri Department of Natural Resources, Administrative Officer, Planning and Zoning Commission and City Council, install individual disposal devices on individual lots within the subdivision. All such individual devices shall be constructed and maintained in accordance with the regulations and requirements of the Missouri Department of Natural Resources and the City.
Water Lines. The subdivider shall provide the subdivision with a complete loop-type water distribution system adequate to serve the area being platted. The system shall include a connection for each lot, water mains a minimum of six (6) inches in diameter and fire hydrants spaced a maximum of five hundred (500) feet apart. The Planning and Zoning Commission shall not approve the final plans for such systems until the Missouri Department of Natural Resources certifies to the Commission that the water supply system is in compliance with the applicable regulations of the State of Missouri and is in accordance with applicable City ordinances.
Adequate surface and subsurface drainageways for the removal of stormwater shall be provided by the subdivider. The extent to which storm drainage facilities shall be required shall be based upon an analysis of need prepared by a registered professional engineer. The analysis shall be based upon a rational method of computing stormwater runoff, using the maximum of one (1) hour rainfall to be expected within a ten (10) year time period. Times of concentration, soil infiltration rates and other variable factors to be used in the analysis shall be discussed with and approved by the Administrative Officer during the preliminary considerations of the subdivision.
A stormwater system, with surface inlets, shall be provided by the subdivider in all cases where curb and gutter are to be installed and whenever available evidence indicates that such a system is necessary as a result of natural surface drainage.
In the absence of a storm sewer system, a water-retarding grass shall be planted in the strip between the sidewalks and the surfacing edge of the street.
Any person proposing to locate a structure of a use within one hundred (100) feet of any stream or main drainage channel shall include a statement by a registered professional engineer based on a study of the watershed area and the probable runoff; that the structure or use in the location proposed will leave adequate space for the flow of floodwater; provided however, that no building shall be permitted within fifty (50) feet of the top of the bank of any stream or drainage channel.
A water-retarding grass shall be planted by the subdivider along any stream or open drainage channel in an area extending a minimum of fifteen (15) feet on either side of the top of the bank of any stream or drainage channel within or adjacent to a proposed subdivision.
All electrical and telephone utility lines shall be installed underground in accordance with the provisions specified in the Missouri Public Service Commission General Order No. 52 and amendments thereto.
Where gas, telephone and electric service lines are placed underground throughout the subdivision, the mains, lines, cables and conduits shall be located within easements or public rights-of-way in separate trenches and in a manner which will not conflict with other underground services. All controls, valves, transformers and terminal boxes shall be located so as not to be hazardous to the public. Should the Commission allow electric and telephone lines to be carried on overhead poles, rear and side lot easements shall be provided if necessary.
All excavations for public utilities made under paved areas shall be properly backfilled with approved granular materials thoroughly compacted in place and street repairs shall be completed to restore the street surface. All such repairs or reconstruction shall be at the expense of the developer or utility involved. No excavation of any street may be undertaken until all necessary permits are obtained.
All unpaved or otherwise unimproved areas within public rights-of-ways or public use areas shall be landscaped in a manner approved by the Planning and Zoning Commission. In informal plantings of street patterns, informal plantings of trees in accordance with an approved landscape development plan may be permitted. In no case shall trees be planted in an area where they may cause damage to underground service utilities.
All landscaped strips, parkways and screening areas dedicated to the public shall be graded, seeded and planted in an appropriate manner. Where shrubs are required for the purpose of screening, specimen, density and other pertinent features shall be approved by the Planning and Zoning Commission.
Monuments And Markers.
All property surveys shall be conducted according to the current minimum standards for property surveys as set out by the State Land Survey Authority. All monuments and markers shall be established and installed to meet the requirements for monumentation of the Missouri Land Survey Authority.
Monuments shall be provided by the subdivider and so placed that the center point shall coincide with the intersection of the lines to be marked, with the top of the monuments level with the surface of the ground (or underground where necessary) after final grading.
All permanent monuments required by the State Land Survey Authority shall be of a type and installed according to the requirements of the State Land Survey Authority. All other markers shall consist of galvanized steel, wrought iron pipe or steel bars at least twenty-four (24) inches in length and one-half (½) of an inch in diameter.
Markers shall be set by the subdivider:
At the intersection of all lines forming angles in the boundary of the subdivision;
At the intersections of street right-of-way lines and at the beginning and end of all curves along street property lines;
At all points where lot lines intersect street right-of-way lines;
At all angles in the lot property lines; and
At all other lot corners.
A permanent bench mark shall be accessibly placed and accurately noted on the subdivision plat, the elevation of such bench mark to be based on a United States Geological Survey datum.