(a) Construction Plans and Details.
(1) A. Drawings showing cross-sections, profiles, elevations, construction details and specifications and cost estimates for all required improvements shall be prepared by a registered civil engineer. The construction plans shall be approved by the Engineer and after approval shall become the property of the Municipality.
B. Plans shall be prepared in ink on mylar film and shall be on standard size 24" x 36" sheets. Should more than three (3) plan sheets be required, a title sheet shall also be included, on which shall be shown the allotment name, and a small scale index map showing the names or letter designation of all proposed streets. The distance from the allotment line, or a street in said allotment, to a known landmark shall also be shown. A suitable title block shall be included on each sheet in the lower right corner.
(2) A. The developer shall submit on U.S.G.S. Topo maps, or other suitable maps, information showing the areas to be drained and submit all data used by his engineer to design the drainage ditches and to determine pipe sizes and structures. The Commission will not review any portion of a subdivision located in areas subject to periodic flooding as shown on the City of Twinsburg Flood Insurance Rate Map, unless the developer or subdivider can prove to the satisfaction of the Engineer by construction plans that such improvement will be made so as to render the area substantially safe from such flooding and that he will complete the work before approval by Council of the record plat. The methods used in calculating sizes of pipe and structures and the design and location shall be acceptable to the Engineer.
B. A complete drainage study shall be made, using the rational method, with the variable adjusted to suit the particular locality, which shall be subject to approval of the Engineer. A complete computation sheet shall be submitted, completely filled out and showing the pipe or sewer size selected. Consideration shall be given to the theory of critical flow and the grades of storm sewers and culverts shall not be arbitrarily increased in order to reduce the required pipe size.
C. Should a structure larger than standard pipe size be required within the allotment, a bridge or sectional plate culvert may be designed, subject to approval of the Engineer. Separate sheets for such structure shall be included in the plans, completely detailed and indicating the highway loading for which it was designed.
(3) Plan and profile of all streets shall be prepared on half plan and half-profile sheets, with the street plan at the top of the sheet and the profile at the bottom. Horizontal scale shall be not greater than fifty feet (50') to the inch and the vertical scale, five feet (5') to the inch, or one-tenth (1/10) of the horizontal scale.
(4) A. Plan sheets shall show the street centerline, centerline sectioning, street names or letter designation, sublot numbers, right of way lines, pavement lines, storm and sani-tary sewer lines, water lines, inlets, manholes, culverts, gutter lines, guard rail, monuments, the P.C. and P.T. of all horizontal curves, together with the curve data, appropriate notes covering construction, a title block, and north point. Sheets shall be numbered in an orderly consecutive manner so that one sheet follows the preceding sheet in a logical sequence.
B. The profile portion of the sheet shall show the original ground profile at the centerline and at both building setback lines and the proposed profile grade with all vertical curve data including the calculated non-passing sight distance for all convex curves (Minimum sight distance shall be three hundred feet 300' from a height of four and a half feet (4 1/2')). The proposed water line and storm and sanitary sewers, including manholes and inlets with the sizes, grades and invert elevations of each, shall be shown as well as all culvert pipe with its location, size, type and class and invert elevations of the two ends.
C. Stationing, corresponding to the plan stationing, shall be shown on the profile, and sea level elevations shall be indicated thereon. Location and description of the U.S.G.S. Bench mark used shall be shown in a box, either on the plan or profile potion of the sheet.
(5) The typical section of the proposed roadway selected from these regulations shall be included, preferably on the sheet with other details of construction. The typical section shall be half-width and shall show the right of way width, pavement width, berm width, or curbs, location of gutters, or curbs, storm sewers, sanitary sewers, water mains, inlets, guardrail, etc. The vertical scale may be exaggerated to show the thickness of each layer of roadway material, its kind and covering specifications. Appropriate notes for each type of material proposed to be used shall be placed directly below the section.
(6) Construction details for all special types of construction proposed, shall be included, preferably on the separate sheet with the typical section. Included shall be special ditch checks, headwalls, concrete aprons, unusual size inlets and manholes, guardrails, barricades, cut-off walls, cradles, etc.
(7) On the topographic sheet to be included with the plans, shall be shown the area in acres draining to each inlet. Each area shall be numbered or lettered, with its outline clearly shown.
(8) Two (2) complete sets of all construction plans and computations shall be submitted to the Engineer for approval. In cases where only slight modification in the plans are found necessary, a copy will be marked and made available to the designing engineer for these corrections. If extensive modifications are required, the Engineer may reject the plan and approval will not be given. When satisfactory, the tracings shall be brought to the Municipal Engineer for his signature. The design engineer will retain the original to add "as built" information. The design engineer shall submit five (5) copies of the signed plan for construction purposes to the Engineer. Contractors must work from an approved, signed copy of the plans.
(9) Watercourses within the street right of way or alongside lot shall be piped or channeled to a natural watercourse or storm sewer if nearby. Material and construction shall be in accordance with the specifications outlined in the Subdivision General Notes.
(10) Any development with frontage on an existing public dedicated Street shall be improved as required by City Council. In no case shall the improvement required be less than set-ting ditches back a standard distance from the existing pavement and back sloping the lots in accordance with the typical section.
(b) Modifications.
(1) If it becomes necessary to modify the improvements as approved due to unforeseen circumstances, the subdivider shall inform the Engineer in writing of the conditions requiring the modifications. Written authorization from the Engineer to make the required modifications must be received by the subdivider before proceeding with the construction of any modified improvements.
(2) At the completion of the construction and before acceptance, the subdivider shall submit the original set of mylars to the Engineer with all "as built" information on the plans as a permanent record, showing the locations, sizes and elevations of all improvements as constructed.
(Ord. 173-2000. Passed 12-17-00.)