(A) Any entrance whether in a rural or urban area, shall not obstruct or restrict the normal water drainage along or across the county road, unless suitable provisions are made therefor. The Public Works Superintendent shall be satisfied that the type, size, and installation of the drainage features proposed in the application are adequate for present and foreseeable future requirements and have a reasonable life span. The type of drainage pipe material shall be approved by the Public Works Superintendent.
(B) Requirements for drainage shall be as follows:
(1) Necessary drainage structures for an entrance shall not be tied onto an existing roadway drainage structure unless the necessary junction boxes, manholes, and catch basins are installed by permittee in accordance with county specifications.
(2) The size, length and type of the entrance pipe shall be as required by the Public Works Superintendent, but in no case shall be less than 15 inches in diameter and not less than 20 feet in length.
(3) All entrance pipe shall meet appropriate Public Works Department specifications and requirements. Pipe shall be of sufficient length to prevent end damage and may require that the permittee provide concrete headwalls. Sloped box inlet or outlet may be required by the County Superintendent, (Standard Drawing No. RDB 110-01 or 111-02).
(4) Valley gutters constructed of concrete or bituminous material, which meet Public Works Department standards, may be used in lieu of entrance pipe where such pipe cannot be placed.
(5) Where long lengths of pipe are used, catch basins or clean-out boxes shall be installed at approximate intervals of 50 feet based on pipe diameter of 15 inches. Special consideration may be given to placement of clean-out boxes at longer intervals for pipe with larger diameters. Boxes shall also be constructed at all angles in pipe alignment.
(6) When necessary, gratings and catch basins must be employed to intercept and prevent water flowing from the driveway over the sidewalks or roadway.
(7) Utilities are not to be placed in or through existing drainage structures.
(8) When a fill is to be placed against an existing roadway, such fill shall be constructed to intersect the outside shoulder edge and slope away from the road on a 6:1 slope to the ditch flow line or a depth of three feet. Furthermore, special drainage features, as required by the Public Works Superintendent, shall be required of the applicant to adequately drain the road bed and shoulders. This refers to french drains or toe drains in the existing fill.
(9) Occasionally, underpavement drainage is provided by sand, crushed stone or other types of drains from the pavement through the shoulder of the road. Requests to join the pavement at these existing drainage points must accompanied by plans showing the method proposed to extend these drains so that their original purpose will be continued. This provision is applicable to commercial and private entrances.
(10) Any proposal to alter or significantly increase a drainage area, run-off factors or change in any way a drainage structure must be accompanied by a complete drainage survey (upstream and downstream) based on a 25-year and 100-year storm with hydraulic analysis of all affected drainage structures in the area and prepared by a registered, licensed engineer.
(Ord. 620.1, passed 3-1-79; Am. Ord. 101.00, passed 6-13-95) Penalty, see § 95.99