[Ord. No. 777 §26-126, 3-23-1994]
The classifications, extent, width, grade and location of all streets shall conform to the Comprehensive Plan and major street plan. Where not shown, the arrangement and design standards of streets shall conform to the provisions herein.
The arrangement of streets in new subdivisions shall be coordinated with existing, proposed and anticipated streets outside of the subdivision. Provision shall be made for the continuation of existing streets in adjoining areas.
When a new subdivision adjoins a tract susceptible to being subdivided, new streets shall be extended to the boundaries of such tract.
Streets shall be related appropriately to the topography and street grades shall conform as closely as practical to the original topography.
Street jogs with centerline offsets of less than one hundred fifty (150) feet shall be prohibited.
Local streets shall be laid out so as to discourage through traffic.
Permanent dead-end streets or cul-de-sacs shall be no longer than five hundred (500) feet, shall provide at the closed end a turnaround having a radius (measured to the back of curb) of at least forty (40) feet and shall provide curb elevations as shown on Standard Drawing No. 10. The right-of-way of a cul-de-sac shall have a diameter of one hundred (100) feet.
Every lot shall have access to a road that provides reasonable ingress and egress for emergency vehicles as well as for the intended use of the lot.
When a subdivision abuts or contains an arterial street, the Planning and Zoning Commission may require marginal access streets or other streets as may be necessary for adequate protection of residential properties and to provide separation of through and local traffic.
Halfstreets shall be prohibited except where such streets, when combined with a similar street (developed previously or simultaneously) on property adjacent to the subdivision, creates a street that meets the right-of-way and pavement requirements of Section 400.460.
The developer shall reimburse the City for cost of any street signs and street light needed in the development as determined by the City.
[Ord. No. 777 §26-127, 3-23-1994]
Clearing and grubbing shall be performed within the right-of-way and easement limits shown on the plans. All timber, brush, roots, stumps, trees or other vegetation cut during the clearing operations shall become the contractor's responsibility to dispose of and shall be either removed from the project site or satisfactorily disposed of on site.
[Ord. No. 777 §26-128, 3-23-1994]
Streets shall be graded in accordance with the lines and grades on plans approved by the City. Before placing curb and gutter or base on a graded subgrade, the subgrade shall be compacted to ninety-five percent (95%) Proctor for a depth of four (4) inches in accordance with MO-DOT 209 and Standard Drawing No 5.
Independent lab testing for compaction of a subgrade shall be provided to the City at the developer's expense. Proof-rolling with a tandem axle, fully loaded dump truck may be required at the direction of the City Engineer or City Public Works Director. Areas found to be soft or composed of unsuitable material, whether in subgrade or below subgrade, must be removed and recompacted with suitable materials. All embankments or fills shall be made in one (1) foot lifts with suitable material. The fill shall be rolled with a sheepsfoot roller after each lift, followed by a smooth-faced roller, each weighing a minimum of eight (8) tons.
[Ord. No. 777 §26-129, 3-23-1994]
Base rock course for streets shall be four (4) inches thick, unless otherwise directed by the City Engineer. The base rock course shall be compacted to ninety-five percent (95%) and shall consist of crushed stone MO-DOT 304 Type 1 and shall be utilized in conformance with Standard Drawing No. 5. Premoistened or plugged base course shall be preferred.
Independent lab testing for compaction and thickness of the base course shall be provided to the City at the developer's expense. Proof-rolling with a tandem axle, fully loaded dump truck shall be required on the base course. Areas found to be soft or composed of unsuitable material, whether in base course or below the base, must be removed and recompacted with suitable materials.
[Ord. No. 777 §26-130, 3-23-1994]
A total of five (5) inches of asphalt base shall be provided in two (2) separate lifts of three (3) inches and two (2) inches in conformance with MO-DOT Section 301. An additional two (2) inch asphalt surface wear course shall be provided in conformance with MO-DOT Section 401-BP2. The base asphalt courses and asphalt surface course shall be compacted to ninety-five percent (95%) and shall be utilized in conformance with Standard Drawing No. 5. Independent testing for asphalt density/compaction and asphalt extractions shall be provided to the City at the developer's expense. Independent coring for asphalt thickness of the asphalt base and asphalt wear surface may be required by the City at the developer's expense.
[Ord. No. 777 §26-131, 3-23-1994]
Where soils are unusually unstable, it may be required for the developer to have soil tests run and a pavement design made by a qualified soils engineer.
[Ord. No. 777 §26-132, 3-23-1994]
All streets shall be constructed with concrete curb and gutters in conformance with Standard Drawing No. 5. The concrete forms shall be metal, free of marks or kinks and shall be rigidly held in position. The use if a slipline curbing machine is preferred. Expansion and control joints shall be provided as noted on Standard Drawing No. 5.
Stormwater curb inlets and boxes shall be constructed in conformance with Standard Drawing No. 15.
[Ord. No. 777 §26-133, 3-23-1994]
Cut and fill slopes on any street right-of-way may not exceed 2:1.
[Ord. No. 777 §26-134, 3-23-1994]
The minimum grade on a finished public street shall be one-half percent (0.5%). The maximum grade on a street shall not be greater than six percent (6%) unless no other practical alternative is available. However, in no case may streets be constructed with grades that create a substantial danger to the public safety.
Vertical Curves. The length of vertical curves shall be no less than that determined by the formula L = KA, where:
L = Length of Vertical Curve
A = Algebraic Difference in Grades
K = Determined by the following Table of "K" Values:
[Ord. No. 777 §26-135, 3-23-1994]
Intersections involving the junction of more than two (2) streets shall be prohibited.
Streets shall intersect as nearly as possible at right angles and no two (2) streets shall intersect at less than sixty degrees (60°).
Except where no other alternative is practical or legally possible, no two (2) streets may intersect with any other street on the same side at a distance of less than four hundred (400) feet measured from centerline to centerline of the intersecting street. When the intersected street is an arterial, the distance between intersecting streets shall be at least one thousand (1,000) feet.
Street curb intersections shall be rounded by a tangential arc with a minimum radius of twenty-five (25) feet for intersections of two (2) residential local streets and thirty (30) feet for intersections involving collector or arterial streets. Where substantial use is anticipated by large vehicles, such as recreational vehicles or semi-trailers, the curb radius shall be increased to accommodate the anticipate use.
Design Speed, Sight Distance, Centerline Radius.
[Ord. No. 777 §26-136, 3-23-1994]
At no-stop intersections, the intersection shall be constructed so that a person standing at a location on the centerline of any street ninety (90) feet from the intersection of the street centerlines has an unobstructed view to a point located on the centerline of the intersecting street ninety (90) feet (in either direction) from the intersection of the street centerlines. See Standard Drawing No 1.
At stop intersections, the intersection shall be constructed so that a person standing ten (10) feet back of the intersection of right-of-way lines on the stop street has an unobstructed view to a point on the right-of-way line of the intersecting through street located seventy (70) feet from the intersection of the right-of-way lines. See Standard Drawing No. 2.
[Ord. No. 777 §26-137, 3-23-1994]
At street intersections, the intersections of the paved surfaces shall be rounded with a minimum radius as shown in Standard Drawing No. 4. Where streets intersect at less than right angles, a greater radius may be required.
[Ord. No. 777 §26-138, 3-23-1994]
All driveway entrances and other openings onto streets within the City's planning jurisdiction shall be constructed so that:
A driveway entrance shall be constructed to keep stormwater from entering the driveway from the street and running into garages and shall conform to Standard Drawing No. 6.
[Ord. No. 777 §26-139, 3-23-1994]
Sidewalks shall be at least four (4) inches thick, at least four (4) feet in width, shall have a base of at least two (2) inches of compacted crushed stone and shall be constructed with expansion control joints in conformance with Standard Drawing No. 6.
Whenever the Board of Aldermen finds that a means of pedestrian access is necessary from the subdivision to schools, parks, playgrounds or other roads or facilities and that such access is not conveniently provided by sidewalks adjacent to the streets, the developer may be required to reserve an unobstructed easement of at least ten (10) feet in width to provide such access.
Where required, wheelchair ramps shall be constructed in accordance with Standard Drawing No. 9.
[Ord. No. 777 §26-140, 3-23-1994]
All utilities and improvements which are to be installed in street rights-of-way shall be completed prior to construction of the street.
[Ord. No. 777 §26-141, 3-23-1994]
The required inspections for street improvements are:
When construction is started.
After subgrade has been prepared.
When curb construction is started.
After curbs are finished.
After curb backfill is completed.
During black base placement.
When coring and proof-rolling surfaces and when all layers of asphalt hot mix are being placed.
After all material/trash has been cleared from the street and right-of-way and all lot pins have been set.
Final inspection for approval.
Core test will be taken at developer's expense to check for thickness, at the City's discretion.
Independent lab testing of new public streets for density/compaction and thickness of the subgrade (dirt), subbases (crushed stone), asphalt base and asphalt surfaces are required and shall be provided to the City at the developer's expense. (Proctor test for dirt and stone compaction and extraction and Marshall tests for asphalt, mix and density on each asphalt layer.)