The improvements hereby required shall be designed, furnished and installed by the subdivider in accordance with the provisions of these Subdivision Regulations and other regulations of the State and County. They shall be installed after the final plat is approved or, in lieu thereof, when financial guarantees for such installation have been approved by the Director of Law and the City Engineer prior to recording of the final plat. The subdivider shall provide and install, within the proposed subdivision, improvements as required by the Planning Commission and the City Engineer.
(a) Drainage. A drainage system shall be designed and constructed by the subdivider to provide for the proper drainage of the surface water of the subdivision and the drainage area of which it is a part. To this end the subdivision shall be graded according to the following requirements and methods:
(1) Drainage plan. Prior to the start of construction of either structures or streets, the subdivider shall furnish a plot plan showing the slab or floor elevation of each structure proposed to be constructed. He shall also show, by the use of arrows, how he proposes to surface drain each lot and shall provide such other information as may be required by the City Engineer. The subdivider shall also submit topographic maps showing the area to be drained, with calculations prepared by a licensed engineer in determining the proposed storm water collection system.
(2) Drainage requirements; grading. No final grading or sidewalk or pavement construction or installation of utilities shall be permitted on any proposed street until the final plat has been approved or conditionally approved. The subdivider shall grade each subdivision as specified herein in order to establish street, block and lot grades in proper relation to each other and to topography, as follows:
A. Street grading plan. A grading plan shall be prepared for the streets along with street improvement details. The grading of the roadway shall extend the full width of the right of way. Planting strips shall be graded at a gradient of not less than two percent nor more than three percent upward from the curb to the sidewalk or property line, unless otherwise approved by the City Engineer.
B. Block grading. Blocks shall be graded as follows:
1. A ridge along rear lot lines, ensuring drainage into the streets; or
2. Parts of all lots draining to a sidewalk or swale along rear lot lines.
C. Lot grading. Lots shall be graded so that water drains away from each building at a minimum grade of two percent. The elevation of a property line swale shall be a minimum of six inches below the finished house grade. Surface drainage swales shall have a minimum grade of one- half of one percent and shall be designed so that surface water will drain into a driveway, street gutter, storm sewer, drain inlet or natural drainage way. Every effort shall be made to preserve and maintain the natural grade of a lot and/or block, subject to approval of the City Engineer. Grades of driveways shall be a minimum of four-tenths of one percent and a maximum of fifteen percent. All grading must be completed prior to occupancy.
D. Topsoil. If grading results in the stripping of topsoil, the topsoil shall not be removed from the site or used as spoil but shall be uniformly spread over the lot after grading is finished.
E. Trees. As many trees as can be reasonably utilized in the final development plan shall be retained and the grading adjusted to the existing grade at the base of the trees. For single-family residential lots eighty feet in width or less, at least one street tree shall be required. For single-family residential lots which have no trees, at least two trees shall be planted on each lot. Plans for planting such trees shall be approved by the Planning Commission. (see subparagraph (b)(6) hereof)
(3) Drainage system requirements. (EDITOR'S NOTE: By Ordinance 22-81, passed April 27, 1981, Council adopted a new storm water drainage manual to replace former subsection (a)(3) hereof, a copy of which is on file with the Clerk of Council.)
(4) Detention/retention basins.
A. Definitions: As used in this subsection inclusive:
1. "Channel" means a natural or artificial watercourse, which continuously or periodically contains moving water or which forms a connecting link between two bodies of water. It has a definite bed and banks which confine the water. "Channel flow" means the water flowing within the limits of the defined channel.
2. "Developer" means any person who acts in his own behalf or as the agent or an owner of property and engages in alteration of land or vegetation, in preparation for, or undertaking construction activity.
3. "Development" means any action, in preparation for, or undertaking, construction activity which results in an alteration of either land or vegetation.
4. "Design and Analysis of Detention/Retention Basin Manual" means the technical design manual prepared by the Engineering Division of the City.
5. "Ditch" means an open channel either dug or natural for the purpose of drainage or Irrigation with intermittent flow. (See stream, drainageway and grassed waterway.)
6. "Drainageway" means a route or course along which water moves or may move to drain an area.
7. "Emergency flow way" means the flow routes and drainageway necessary to convey the 100-year storm.
8. "Flood" means the temporary inundation of any land not normally covered by water due to heavy rainfall or runoff or due to a temporary rise in the level of rivers, streams, watercourses or lakes.
(A) "Average annual flood" means a flood equal to the mean of discharges of all the maximum annual floods during the period of record.
(B) "Regional flood" means the name applied to the 100-year flood in flood plain information reports. The 100-year flood has a one percent probability of being equaled or exceeded in a period of 100 years.
(C) "Maximum probable flood" means the largest flood discharge believed possible considering the meteorologic conditions and snow cover on the watershed.
9. "Floodway" means the channel of the watercourse and those portions of the adjoining flood plain which are used to convey the regional flood.
10. "Grassed waterway" means a broad and shallow natural course or constructed channel covered with erosion resistant grasses or similar herbaceous cover and used to conduct surface water.
11. "Hydrologic and hydraulic study" means engineering study to determine rates, volumes and distribution of storm runoff and its collection, storage and conveyance.
12. "Runoff" means the portion of rainfall, melted snow or irrigation water that flows across the ground surface and eventually is returned to streams.
(A) "Accelerated runoff "means increased runoff due to less permeable surface area primarily caused by urbanization.
(B) "Peak rate of runoff" means the maximum rate of runoff for any storm.
(C) "Runoff volume" means the total quantity or volume of runoff during a specified time period. It may be expressed in acre-feet, in inches-depth of the drainage area, or in other units of volume.
13. "Storage" means the control, retention or detention of runoff.
(A) "Detention storage" means storm runoff collected and stored for a short period of time and then released at a controlled rate. (Dry Pond)
(B) "Retention storage" means storm runoff collected and stored for a short period of time and which is released at a controlled rate leaving in the facility a minimum pool of water. This facility is often associated with water-related recreational or aesthetic uses. (Wet Pond)
14. "Storage facility" means any facility used to store, retain or detain storm runoff, which shall include but not be limited to retention and detention storage facilities, rooftop or parking lot ponds, basins, depressions and pools.
15. "Storm frequency" means the average period of time in which a storm of a given duration and intensity can be expected to be equaled or exceeded.
16. "Storm drainage system" means the surface and subsurface system for the removal of water from the land, including both the natural elements of streams, gullies, ravines, marshes, swales and ponds, whether of an intermittent or continuous nature, and man-made elements which include conduits and appurtenant features, culverts, ditches, channels, storage facilities, streets and the storm sewer system.
(A) "Initial drainage system" means that part of the storm drainage system which is used regularly for collecting, transporting and disposing of storm runoff, snow melt and miscellaneous minor flows. The capacity of the initial drainage system should be equal to the maximum rate of runoff to be expected from a design storm which may have a frequency of occurrence of once in two, five or ten years. The initial system is also termed the "convenience system", "minor system" or the "storm sewer system" and may include many features ranging from curbs and gutters to storm sewer pipes and open drainage ways.
(B) "Major drainage system" means that storm drainage system which carries the runoff from a storm having a frequency of occurrence of once in 100 years. The major system will function whether or not it has been planned and designed and whether or not improvements are situated wisely in respect to it. The major system is also termed the "emergency flow way". The major system usually includes many features such as streets, ravines and major drainage channels. Storm sewer systems may reduce the flow in many parts of the major system by storing and transporting water underground.
17. "Stream" means a course of running water usually flowing in a particular direction in a definite channel and discharging into some other stream or body of water.
18. "Watercourse" means a channel in which a flow of water occurs either continuously or intermittently in a definite direction. The term applies to either natural or artificially constructed channels.
B. Design and Analysis of Detention/Retention Basin Manual.
The Manual is hereby adopted by the City, and the policies, standards, specifications and provisions contained therein shall apply to the development of all subdivisions in the City.
C. Hydrologic and hydraulic studies.
1. A hydrologic and hydraulic study of each subdivision shall be submitted prior to final plat approval and as part of the construction drawings.
2. These studies will be used to establish the adequacy of the drainage system of the development site. As part of these studies, the adequacy of the storm drainage facilities necessary to carry the runoff from the initial storm design shall be shown. Also the flow routes and drainageways necessary to convey the 100-year storm (the emergency flow way) through the development shall be shown. Necessary easements shall be shown.
3. These studies will also be used to establish the adequacy of the drainage system of the proposed development to receive and convey any initial and major storms from dominant (upstream) property.
4. These studies will also be used to establish the adequacy of the drainage system of the proposed development so as not to create or worsen drainage problems downstream. As part of these studies, storage facilities, when used, will be located and iden tified by type.
D. Stormwater runoff limitations.
1. If the hydrologic and hydraulic studies reveal that the proposed development or subdivision would not increase the total volume of runoff, the peak rate of runoff after development shall not be greater than the peak rate of runoff before development for all return periods of storms up to 100 years.
2. If the hydrologic and hydraulic studies reveal that the total volume of runoff is increased, the peak rate of runoff after development from the critical storm shall not exceed the predevelopment peak rate of runoff from a one-year frequency storm for a twenty-four hour period. The critical storm shall be determined in accordance with the Manual and the peak rate of runoff for each storm of greater or lesser frequency shall be determined in accordance therewith. Provided, however, that the peak rate of runoff after development may not exceed the peak rate of runoff before development.
E. Subdivision drainage system.
1. Storm drainage facilities for the subdivision or development shall be designed to accommodate runoff from the five year storm frequency. Site design and grading plans shall provide emergency drainageways, in order to avoid both damage to structure and endangering public safety, which emergency drainageways shall be designed to accommodate runoff from storms exceeding the five year storm frequency, but not exceeding the 100 year storm frequency.
2. The initial drainage system shall be located within street rights-of-way whenever practicable. If the collector facilities cannot be located in street rights-of-way, then they shall be located adjacent to side or rear lot lines where easements shall be provided to, and along, the facilities.
3. All storm water flow from the proposed subdivision, including flows from upstream areas passing through, and further including increased flows attributable to changes in time of concentration or changes in the former runoff factor (imperviousness), shall be conveyed to the proper outlet for the entire tributary area via a natural channel or an artificial channel either or both of which shall be improved so as to be of adequate capacity.
F. Easements and access. Access to flood control or storm drainage facilities for emergency, inspection, maintenance and improvement purposes, shall be provided as follows:
1. Access to flood control or storm drainage ditches, channels and storage facilities, shall be by means of easements. Such easements shall be not less than fifteen feet in width, exclusive of the width of the ditch, channel or other facility it is to serve, and an easement of this type shall be provided on one side of a flood con trol or storm drainage ditch, channel or similar type facility.
2. Access along flood control or storm drainage ditches and channels, shall be by means of easements. Such easement shall not be less than fifteen feet in width, exclusive of the width of the ditch, channel or other facility it is to serve, and an easement of this type shall be provided on both sides of a flood control or storm drainage ditch, channel or similar facility.
3. Access along the initial drainage system shall be by means of easements. Such easement shall be not less than fifteen feet in width, with a minimum of five feet in width on each side of the center line.
4. Access around storage facilities shall be by a ten foot easement in the case of detention dry basins, and twenty-five foot easement in the case of retention wet basins, measured from the line of the design high water level and shall include the storage facility itself.
5. Easements for the emergency flow ways shall be a minimum of fifteen feet in width.
6. Flood control or storm drainage easements containing underground facilities, shall have a minimum width of ten feet.
G. Maintenance. Any portion of the drainage system, including on-site and off-site storage facilities, that is constructed by the developer will be continuously maintained by the owner or owners subsequent in title of the affected lands unless it is officially accepted by the City for maintenance. The developer shall cause the maintenance obligation to be inserted in the chain of title to the affected lands as a covenant running with the land in favor of the City.
(Ord. 154-79. Passed 10-22-79.)
(b) Street Improvements. The subdivider shall design and construct pavements, curbs and gutters of sizes and types not less than set forth in Appendix H (see following these Subdivision Regulations) for all public and/or private streets, drives or parking areas. Pavement cross-sections shall be as shown in Appendix H. The construction and materials shall be as specified by the State of Ohio Department of Transportation Construction and Material Specifications Manual, the latest edition, or by the City Engineer.
(1) Pavements.
A. Type 1 Arterial. Pavement: Eight inch reinforced concrete pavement with three inch sub-base and four inch shallow pipe underdrain. Width: Forty-eight feet including four inch curbs.
Grade: 0.5% Minimum
5.0% Maximum
B. Type 1A Minor Arterial. Pavement: Eight inch reinforced concrete pavement with three inch sub-base and four inch shallow pipe underdrain.
Width: Thirty-six feet including four-inch curbs.
Grade: 0.5% Minimum
5.0% Maximum
C. Type 2 Collector. Pavement: Seven inch reinforced concrete pavement with three inch sub-base and four inch shallow pipe underdrain.
Width: Twenty-eight feet including four-inch curbs.
Grade: 0.5% Minimum
7.0% Maximum
D. Type 3 Subcollector. Pavement: Seven inch reinforced concrete pavement with three inch sub-base and four inch shallow pipe underdrain.
Width: Twenty-six feet including four inch curbs.
Grade: 0.5% Minimum
7.5 Maximum
E. Type 4 Local. Pavement: Seven inch reinforced concrete pavement with three inch sub-base and four inch shallow pipe underdrain.
Width: Twenty-six feet including four-inch curbs.
Grades 0.5% Minimum
8.0% Maximum
F. Type 5 Cul-De-Sac. Pavement: Seven inch reinforced concrete pavement with three inch sub-base and four-inch shallow pipe underdrain.
Width: One hundred feet Diameter
Grade: 0.5% Minimum
8.5% Maximum
G. Type 6 Marginal Access. Pavement: Seven inch reinforced concrete pavement with three inch sub-base and four inch shallow pipe underdrain.
Width: Eighteen foot lanes
Grade: 0.5% Minimum
5.0% Maximum
H. Type 7 Rural Residential. Pavement: Eight and one-half inch asphalt or seven inch reinforced concrete pavement with three inch sub-base and four inch shallow pipe underdrain.
Width: Twenty feet, pavement edge to pavement edge.
Grade: 0.5% Minimum
8.5% Maximum
I. Type 8 Rural Cul-De-Sac. Pavement: Eight and one-half inch asphalt: Seven inch reinforced concrete pavement with three inch sub-base and four inch shallow pipe underdrain.
Width: One hundred feet diameter, pavement edge to pavement edge.
Grade: 0.5% Minimum
8.0% Maximum
In rural residential subdivisions with development densities of not more than one dwelling unit per two gross acres, the subdivider shall design and construct pavements of sizes and types not less than those set forth in paragraphs (b)(1)H. and I. hereof and in Appendix H for all public and private streets. The affected township shall decide which pavement will be required for each street type.
(Ord. 78-79. Passed 6-11-79; Ord. 82-82. Passed 6-28-82.)
(2) Curbs and gutters. Concrete curbs and gutters, either separate or integral with the pavement, shall be provided where indicated by the typical cross-section shown in Appendix H (see following these Subdivision Regulations).
(3) Sidewalks. Sidewalks shall be provided in the location shown by the typical cross-section in Appendix H or where prescribed by the Planning Commission. Sidewalks shall be constructed of concrete four inches thick with the thickness increased to six inches where the sidewalk is crossed by a driveway. The construction and materials shall be as specified in Item 608 of the State of Ohio, Department of Transportation Construction and Material Specifications Manual, the latest edition.
(4) Street name signs. The subdivider shall install street signs at all street intersections. The signs shall conform to the specifications of the Director of Public Service and shall be mounted at a height of approximately seven feet above the top of the curb or the crown of the pavement. They shall be located on diagonally opposite corners on the far right-hand side of the intersection for traffic on the more important streets.
(5) Street lights. The subdivider shall contact Council to arrange for the installation of public street lights in the subdivision. The installation of private street lights shall be as prescribed by the Planning Commission.
(6) Trees. Street trees shall be provided as follows:
A. Species. The trees shall be of species which are resistant to damage and disease and which do not cause interference with underground utilities or street lighting. The species of trees suggested are red maple, Norway maple, sugar maple, sycamore maple, red oak, thornless honey locust, London plane tree, amur cork tree, sweet gum, buckeye, ruby red horsechestnut, European hornbeam, hornbeam, American hop hornbeam, Chinese hackberry, hackberry, maidenhair tree and European linden. Trees which have undesirable characteristics such as fruit, low branches, unpleasant odors, excessively thick foliage, susceptibility to disease or attack by insects or large root systems, such as poplar, willow, cottonwood, American elm, ailanthus, mountain ash, silver maple, ash leaved maple and Oregon maple are prohibited in the planting strip. Poplar, willow or cottonwood trees, if planted on private property, shall be located not less than 100 feet from any public sewer.
B. Location. Street trees shall be spaced so that there will be approximately ten feet between branch tips when the trees are full grown. No trees shall be planted within forty feet of the intersection of two street right-of-way lines. Approaches to buildings should be considered when locating trees.
C. Size. Trees shall be at least one and one-half inches in diameter, one foot above the ground. The lowest branches shall be not less than seven feet and no more than ten feet above the ground.
(7) Planting screens or fences. The Planning Commission may require and permit planting screens or fences where double-frontage lots abut a major arterial street and/or between a major arterial thoroughfare and a marginal access street, provided that such planting screens or fences do not constitute a safety hazard. A plan of proposed planting screens or fences shall be submitted for approval with the final plat.
(8) On-site landscaping. The Planning Commission may require additional on-site landscaping.
(c) Sewer and Water Facilities. Adequate central sanitary sewerage, storm sewerage and water supply systems shall be provided by the subdivider, either by the installation of new systems or by connection to existing systems which are deemed adequate by the County Sanitary Engineer to handle the additional demands and volume which will result from the proposed subdivision. The subdivider, prior to the submission of a plat for approval by the Planning Commission, must receive written approval for the extension or installation of a central water system and central sanitary sewerage system from the County Sanitary Engineer, the City Engineer, the County Health Department, the Ohio Department of Health and the particular private or public utilities involved. The Planning Commission may grant an appropriate variance from the foregoing requirements when one or more of the following conditions are met:
(1) If each of the proposed lots is two acres or larger in area, has an average of 240 feet or more frontage on a public street and, using the Regional Land Use and Development Plan as a guide, rural density of development appears to be most suitable for the area in which the subdivision is proposed;
(2) If central sanitary sewerage systems cannot be provided because of inadequate stream flow, as determined by the Ohio Department of Health, or because of the inability to connect with existing sanitary sewers, or if central water supply systems cannot be provided because of inadequate water supply, as determined by the Ohio Department of Health, and, using the Regional Land Use and Development Plan as a guide, urban density of development appears to be most suitable for the area in which the subdivision is proposed. Under these conditions, the subdivider may be permitted to develop interim individual sewage disposal and/or water supply systems, provided that written evidence is submitted that the subdivider has demonstrated to the satisfaction of the Ohio Department of Health and the County Health Department that subsoil conditions are suitable for such interim sewage disposal facilities.
(d) Public Sites. The Planning Commission shall require the dedication of land for parks, playgrounds, open space and/or school sites, as specified in Table One herein, for lands outside the Municipality, provided that the Township Trustees have certified to the Planning Commission, prior to the official filing of the preliminary plan, a request that such dedication be required as a condition precedent to the approval of subdivisions in the Township.
Where a comprehensive Land Use and Thoroughfare Plan, showing the planned location of such public sites, has been adopted by the Planning Commission and the Township Trustees and certified to the Commission, the Commission shall require that such dedication be in conformity with such Plan. Where the land area shown on such Plan for such public sites exceeds the amount required by Table One herein, such additional land shall be reserved for a period of one year to permit such land to be acquired by the appropriate public body.
TABLE ONE
LAND AREA REQUIRED FOR PUBLIC USE
Average Lot Area in Square Feet Portion of Acre Single-Family Residential per Gross Acre and other uses in Subdivision 43,561 or more 0.06 acre 20,001 to 43,560 0.07 acre 12,001 to 20,000 0.08 acre 8,001 to 12,000 0.09 acre less than 8,000 0.10 acre Multifamily 0.12 acre Industrial* 0.05 acre
Business* 0.05 acre |
*Planning Commission may vary requirement.
If no public site is indicated on the Land Use and Thoroughfare Plan, the subdivider, in lieu of dedicating land in the amount indicated in Table One, may, if he desires, pay an amount equal to the improved value of such land as determined by three appraisers, one to be selected by the subdivider, one by the Planning Commission and one acceptable to both. Any payment in lieu of dedication of public land shall be used to purchase school or park sites which shall serve the subdivision for which the payment was made.
It is recommended that public sites for schools be at least ten acres in area; that sites for neighborhood parks total at least seven acres; and that school-park sites be at least fifteen acres in area. It is also recommended that public sites in adjoining subdivisions be located together so that larger, more usable sites are created. Any land dedicated for a public park or open space, other than buffer areas which separate industrial, multifamily or business areas from single or two-family residential areas, shall be graded, fertilized and seeded as follows:
(1) Fertilizing. Commercial fertilizer, 12-12-12, shall be applied at the rate of twenty pounds per 1,000 square feet.
(2) Seeding. Seeding shall include grasses and clover in the following proportions: five percent alsike clover; sixty-five percent creeping red fescue; twenty-five percent Kentucky blue grass; and five percent redtop.
(e) Monuments. Monuments shall consist of one-inch pipe or steel rods set in and running through a concrete block at least six inches in diameter and at least thirty inches long. The bottom of such block shall be set at least thirty inches below the finished grade on the plat and the points at which they may be found shall be designated on such plat. All monuments set in pavement shall be set in standard monument boxes. Where new streets intersect existing streets, the monuments may be placed on the centerline of the new road at the right of way of the existing road. Four monuments shall be set in each plat of ten lots or less and not less than six shall be set in each plat containing over ten lots.
(Ord. 76-79. Passed 6-11-79.)
(Ord. 76-79. Passed 6-11-79.)