(A) Grading. The individual building site or developed lot shall be graded in accordance with Chapter 51, Stormwater Management Code, and Chapter 151, Subdivision Rules and Regulations.
(1) Site plan. The final grading of the site and the associated drainage system must comply, in general, with the above. The site plan shall show, in addition to all improvements, all revisions being made to the site which do not conform to the approved grading plan for the subdivision.
(2) Alteration of existing slopes. When the lot is graded to a higher or lower level than the existing grade, the owner shall provide slopes (max. 3:1), retaining walls, or other approved protection, on his property, to preserve the elevation of the adjoining property. Steeper slopes may be approved by the Building Official in special limited cases.
(3) Grading. Grading shall be done as closely as possible to the following criteria:
(a) Protective slopes around buildings shall slope downward from building foundation to lower areas or drainage swales.
1. The horizontal length shall be ten feet except where restricted by a property line. Where restricted by a property line, a drainage swale shall occur at the property line.
2. The minimum vertical fall of protective slopes in rear yards shall be six inches.
(b) 1. In areas other than the protective slopes, the minimum gradient shall be 2%. When acceptable by the Building Official, lesser gradients than that required above may be installed when a lesser gradient is adequate to drain the lot without detrimental effect upon buildings or other lot uses. The maximum gradient shall be no steeper than 2:1. If an undisturbed slope is held by satisfactory existing vegetation or rock outcropping, no limit shall be imposed on the maximum gradient as long as present and future stabilization is assured. Top and bottom of banks at swales, terraces, etc. shall be rounded or otherwise constructed for convenient maintenance.
2. Water being disposed of between houses shall be channeled along the common property line to the drainage system, but in no case shall water from more than one-half acre be collected and disposed of between houses. If water from more than one-half acre is collected, the drainage system shall be designed in accordance with Chapter 51, Stormwater Management Code.
(4) Major drainage system. All parts of the grading and drainage system shall be in conformity with the requirements for major drainage systems as indicated on the subdivision plan.
(a) Grading shall be done so that the drainage pattern (in place or approved) is not changed, and stormwater ground runoff to adjoining property is not increased, redirected, concentrated or caused to spill off the property in new locations, so as to create stormwater problems on adjacent property.
(b) Stormwater must be directed into the same watershed and in the same general direction that existed prior to the site grading operation. Diversion into other watersheds is not permitted, except when approved for very minor grading areas occurring totally within the newly developed lot, and then only when no problem will be created on adjacent property.
(c) Work which is executed but is not in conformance with the regulations and/or the approved site plan, shall be removed and remedial action taken to bring the property into full compliance.
(B) Drainage. The storm drainage system on each lot shall comply with the above and shall include, but is not limited to the following:
(1) Stormwater disposal. An approved surface and/or sub-surface drainage system for the collection and disposal of storm runoff and sub-surface water from the site to prevent flooding, erosion and standing water shall be installed. Concentrated storm drainage shall be directed to approved surface or sub-surface drainage facilities as required herein.
(2) Adjacent properties. The drainage system shall carry and discharge storm water without producing any adverse effect on adjacent or downstream properties. Retention facilities shall be provided, as required by the Stormwater Management Code, to facilitate the containment and slow release of storm runoff.
(3) Out-flow facilities. The choice of out-flow facilities lies with the property owner, but shall be approved by the city, which reserves the right to require use of another facility. Such facilities shall include, but are not limited to:
(a) Existing surface and piped facilities, such as swales, watercourses, drainage easements, storm sewers, etc. as regulated by the City Engineer.
1. Use of storm sewers must be approved, in concept, by the Public Works Director, and no such sewers shall be considered available, unless it is low enough to allow the slope of the lateral entering it to meet the requirements of the Public Works Director.
2. The storm sewer shall be considered available only if the breaking or cutting of the flat paving in the public right-of-way, or if the tunneling under the street to access the sewer is fully approved by the Public Works Director.
a. Street drainage ditches and street gutters, via an outflow pipe (through the curb, where applicable) as regulated within the public right-of-way, by the Public Works Director.
b. Facilities, on the site, approved by the Plumbing Section, Hamilton County Board of Health and the City Engineer.
3. Surface drainage. Positive surface drainage shall be provided for each lot so there is no pocketing of water on any surface. This can be accomplished by grading or installing catch basins, area drains, underdrains, etc. property connected to approved disposal facilities.
a. Grading shall be done so that the existing natural ground drainage of the area is not impeded, distorted or redirected.
4. Yard drainage. Where no storm sewer is available, no garage apron, driveway, stairwell, window (area) well, foundation drain, walkway, below-grade entrance area, or any below-grade area subject to receiving storm drainage shall be permitted unless it has a gravity drainage system or an approved sump well and pump installation.
a. Outflow shall comply with division (B)(3) of this section, except that no clear water sump discharge shall be permitted into a street gutter or onto a private or public sidewalk or roadway. Sump discharge onto the property must be so that flow onto the sidewalk is restrained without ponding.
5. Building drainage. All new buildings, except accessory buildings less than 800 square feet in area, or buildings with roof overhangs of 12 inches or more that have a side yard of at least six feet six inches from the far edge of the overhang to the property line, shall be equipped with gutters and downspouts.
a. Without gutters. Where no gutters are used the plans submitted for the building permit shall show on a grade plan of the lot that roof runoff water shall follow drainage swales formed by intersecting slopes and that these swales carry water to some natural water course on the same property or to street curb.
b. With gutters. When gutters and downspouts or sump pumps are used, their discharge shall be connected by a pipe to a storm sewer if available. If such sewer is not available, the collector pipe shall run to a street gutter in conformance with division 6.a. below or street drainage ditch if same is available. If neither sewer, gutter nor street drainage ditch is available, the collector shall run to a natural drainage course on the owner's property. The storm sewer shall not be considered to be available if the public right-of-way paving would have to be broken to get to the sewer, or if tunneling under the street would have to be resorted to. Splash blocks may be used in lieu of piping for downspouts provided they drain into approved drainage swales.
6. Work in the right-of-way. The following shall apply to all work done in the right-of-way:
a. Curb cuts. Curb cuts for downspout drains must be made with a saw or other approved cutting tool. Maximum pipe size through the curb shall be three inches nominal. Top surface of the pipe must be at least one inch below the highest part of the curb. The pipe must cross the curb at a right angle to the curb. After cutting and installation of pipe, curb shall be restored to original contours in an approved manner. (Epoxy resin cement or ThoroPatch are acceptable materials for curb repair). Only cast iron pipe or galvanized iron pipe may be used. Said pipe shall extend from the curb to the edge of the right-of-way.
b. Driveway approach. Driveway approach must meet approved standards. The planting strip must be filled, graded and sodded. All utility boxes within the public right-of-way must be at grade level.
c. Additional fee. In addition to the building permit fee, the person or contractor shall be charged for inspection of all work within the street and/or crosswalk right-of-way at the rate of inspection fees in effect at the time of the inspection. The city retains the right to deduct any inspection charges from the bond posted prior to return of the bond amount.
d. Bond amount. Bond amount to be posted by the builder to assure proper compliance of construction within the right-of-way shall be as prescribed in Chapter 156 (Comprehensive Fee Schedule).
e. Hazardous defects. If defects or conditions exist within the right-of-way which is hazardous to the health and safety of the public, the builder will be given written notice of these effects or hazardous conditions by the city. If after three working days these defects or conditions are not corrected, the builder may be cited to court for violation of the code. The city will then correct these defects or hazardous conditions. The city will be reimbursed for its work from the right-of-way bonds. The city may use up to the cash value of the right-of-way bonds on hand to correct these defects of hazardous conditions. The builder will then be required to put up cash for each additional right-of-way bond which will be issued with the maximum amount of cash required to be $500. No further building permits shall be issued to any builder until he has redeposited a sum sufficient to bring his right-of-way deposit account up to its maximum limit of liability.
f. Work within the right-of-way. All work within the right-of-way must be completed and inspections made prior to the issuance of the certificate of occupancy.
(C) Survey. Application for a permit for any new building must be accompanied by the required number of site surveys of the property, prepared by a registered surveyor. This must show, in addition to the lot location, bounds and building location on the lot, including the following information:
(1) Sewers. Type of sewer (such as storm, sanitary, combined) material and size of sewer, sea level elevations of sewer inverts at location of laterals, inlets, outlets, catch basins, manholes (when sewer is to be utilized); the proposed floor level of the lowest floor (including basement or cellar) of building.
(2) Grading. Accurate, field verified, sea level elevations of existing grades; proposed final grades of yard to determine compliance with this section.
(3) Drainage. Drainage pattern and/or facilities that is available for use or which are to be constructed.
(4) Utilities. The location of water, sewer, gas, phone, and any other utility on the lot are required to be shown on the survey plat.
(Ord. 25-2019, passed 8-5-19)