(A) Drainage.
(1) Purpose. These design standards and specifications shall serve as minimum requirements for the handling of surface water and drainage. These procedures and regulations shall govern the development of all new and/or modified drainage systems. The development of such drainage systems shall include the conveyance of surface water to an adequate outlet which is capable of carrying the flow.
(2) Preliminary drainage plan. A preliminary drainage plan for all major subdivisions shall be submitted for review and preliminary approval by the Village Administrator. The plan shall show the general runoff pattern of the area which is to be improved as well as showing the runoff patterns of adjacent areas which affect or may be affected by the proposed improved area. A copy of the preliminary plan required by the Planning Commission may serve as the preliminary drainage plan. Sufficient data shall be supplied for the Village Administrator to check the feasibility of the drainage system and stormwater runoff control as proposed by the developer. The preliminary drainage plan shall be approved prior to the preliminary approval of the subdivision plan by the Planning Commission.
(3) Adequate drainage outlet. Surface water runoff of a development shall be drained off site in accordance with this code. The location of the adequate outlet shall be approved by the Village Administrator. The adequate outlet may consist of a ditch, stream, storm sewer or approved retention basins, having sufficient capacity to accommodate the surface water runoff in a reasonable manner.
(4) Drainage easement. An adequate drainage easement shall be required along any drainage way, ditch, watercourse, stream or storm sewer which is not already within the public right-of-way. The easement shall be of sufficient width to allow cleaning, widening, deepening, replacement or other general maintenance of such drainage course. When it is required of the developer to convey surface water outside the limits of the proposed improved area in order to discharge into an approved adequate outlet, it shall be the responsibility of the developer to obtain easements or rights-of-way for construction and/or maintenance of such drainage course. All drainage easements shall be shown on the plat and construction plans. The drainage easements shall be recorded for public use and the maintenance of such drainage courses shall be the responsibility of the property owners receiving direct benefit therefrom.
(5) Right-of-way for drainage structures. When a drainage structure within the public right-of-way extends beyond the limits of the normal public right-of-way, additional right-of-way shall be provided around the structure to allow for adequate maintenance.
(6) Final drainage plan.
(a) A final drainage plan showing the entire drainage system shall be submitted with utility improvements to the Village Administrator for construction approval. The final drainage plan shall conform to these regulations and to any special conditions that were required by the Planning Commission in approving the preliminary plat. The final plan shall include engineering calculations used in determining the design of the drainage courses, the drainage structures and stormwater runoff control structures.
(b) The following shall serve as a minimum requirement for plans and engineering calculations for the on-site drainage:
1. The total tributary drainage areas entering the improved area;
2. Times of concentration, intensity and runoff coefficients used for determining runoff;
3. Discharge volume in cubic feet per second, velocity and additional data needed to establish that the drainage system will convey the flow to the approved adequate outlet;
4. The plan and profile of all drainage courses to where the system discharges into the adequate outlet;
5. Size and type of all drainage improvements including all drainage structures; and
6. Sufficient contours and grading details to show that the proposed improvements will function adequately. All drainage construction plans shall be sealed with the stamp of a professional engineer registered in the state as required by R.C. Chapter 4733. The drainage plan shall be approved by the Village Administrator prior to construction of any portion of the drainage system.
(7) Storm sewers. The Village Administrator may require a storm sewer system wherever an open ditch may present future problems, such as flooding, erosion or endangers the health and safety of the residents of the subdivision or wherever the pavement classification dictates a storm sewer system should be used. The storm sewer system shall be designed to accommodate the tributary drainage areas of the subdivision. The minimum drainage easement for storm sewers outside of the right-of-way shall be 20 feet in width. This easement shall be shown on both the final plat and the construction plans and it shall be labeled “Public Drainage Easement.”
(8) Culverts.
(a) Culverts shall be used to convey water through a roadway embankment and shall be designed so as not to impose a hazard to the roadway or the surrounding area. Attention shall be given to alignment, grade and sizing so hazards shall not exist.
(b) The design system shall be reviewed and approved by the Village Administrator.
1. All culverts shall be installed, bedded and backfilled in accordance with the State of Ohio Department of Transportation (O.D.O.T.), Construction and Materials Specifications.
2. All conduit shall be reinforced concrete or approved equal.
3. The type of conduit used will be determined by the amount of fill in the embankment in accordance with O.D.O.T. Construction and Materials Specifications.
4. Headwalls and endwalls shall be installed when required by O.D.O.T. design standards.
5. Any special treatment, including catch basins, improved inlets, headwalls, stilling basins, energy dissipators, downstream channel improvements and erosion control shall be taken into consideration by the design engineer.
6. All culverts draining areas larger than 200 acres shall be designated major culverts and shall be designed to convey a 25-year frequency storm.
7. All culverts draining areas 200 acres or less shall be designated minnow culverts and shall be designed to convey a ten-year frequency storm.
(9) Subsurface drainage.
(a) Subsurface drainage shall be used as required to control the flow of ground water. Subsurface drainage is to be used as measure to maintain firm, stable subgrades and foundations; eliminating wet cuts and preventing frost heave; and preventing sloughing and saturation of cut and fill slopes.
(b) Where a roadway consists of a total aggregate buildup with chip and seal surface, it may be determined that an aggregate underdrain will provide adequate subdrainage so long as the roadside ditch remains open and provides an adequate outlet for the aggregate underdrain.
(c) Where a higher classification pavement is being used over any aggregate base or where the ditches are closed in, pipe underdrains shall be used. For roadway structures and slope stabilization, pipe underdrains are to be used as required.
(d) In the design of the pipe underdrain system, consideration shall be given to the type of pipe used, the filter material and the surrounding soils that are to be drained in order to avoid clogging and achieve adequate hydraulic capacity.
(e) The design and construction of all subsurface drainage systems shall be reviewed and approved by the Village Administrator.
(10) Downspout drain lines.
(a) Downspout drain lines may be installed into the storm sewer drainage system. The downspout drain lines should empty into the nearest catch basin or manhole to prevent excessive pipe sizes for the downspout drain lines.
(b) A six inch pipe shall be the minimum size for the collector line.
(c) The design and construction of the downspout drain lines shall be reviewed and approved by the Village Administrator.
(d) Roof drains and sump pumps shall be tied into drains back of the curb connected to the storm sewer system, or if impractical where the lot slopes to the rear and a drainage swale, storm sewer or other outlet method is available, it may be used if approved. All connection into the existing storm sewer shall be inspected and approved by the Village Administrator.
(e) Under no circumstances shall any storm drainage system, downspout drain line or footer drain be allowed to empty into a sanitary sewer.
(11) Hydrologic design.
(a) All calculations for the design rate of runoff (Q) shall be submitted for review and approval of the Village Administrator.
(b) The rational method: Q = CIA
Where: Q = Runoff (cubic feet per second)
C = Runoff coefficient
I = Intensity of rainfall (inches per hour)
A = Tributary area (acres)
Shall normally be an acceptable method for computing the design rate of runoff for tributary areas of less than 200 acres.
(c) The ASCE Manual 1137: Design and Construction of Sanitary and Storm Sewers shall serve as a guideline for formula.
(d) Table 4, Rainfall Intensity and Time of Concentration shall be used in determining the intensity of rainfall.
(e) For tributary areas over 200 acres the Floods in Ohio - Magnitude and Intensity Bulletin by the Ohio Department of Natural Resources or the soil conservation service method may be used in computing the design rate of runoff.
(12) Design frequency structures.
(a) The minimum design frequencies to be considered for drainage structures shall be as follows:
Structures | Frequency (years) |
Bridges | 50 |
Culvert (minor) | 10 |
Flood plain structure | 100 |
Open ditch | 10 |
Storm sewers | 5 |
(b) The design frequency to be considered for an individual structure may be altered by the Village Administrator where there is a flood hazard or where the health and safety of the residents of the subdivision would be endangered by inundation of stormwater.
(13) Open ditches.
(a) The minimum slope of open ditches shall be 1%. All ditches, slopes and areas disturbed by construction shall be seeded and mulched.
(b) Ditch linings shall be installed as follows:
Type of Cover | Allowable Velocity (ft/second) |
Seeded lining | 0—3 |
Sodded lining | 0—5 |
Lining to be approved by Village Administrator | Above 5 |
(c) The minimum dimensional requirements for open ditches shall be a two foot bottom width, one and one-half foot depth, with back slopes graded to a four to one slope unless otherwise approved by the Village Administrator.
(d) All open ditches outside of the normal right-of-way shall be protected with a minimum 20 foot drainage easement.
(e) The easement shall be shown on the final plat and the construction plans and it shall be labeled “Public Drainage Easement.”
(14) Seeding and mulching.
(a) All ditches, right-of-way areas and areas disturbed during construction are to be seeded and mulched. The specifications in Table 5, developed in cooperation with the Soil Conservation Service, outline the minimum requirements that shall be followed for both rate of application and time table for seeding.
Table 5 - Specification for Seeding and Mulching | |||
Kind of Seed | Seeding Dates | Per 1,000 Sq. Ft. | Per Acre |
Table 5 - Specification for Seeding and Mulching | |||
Kind of Seed | Seeding Dates | Per 1,000 Sq. Ft. | Per Acre |
Tall fescue | March 1 to September | 1 pound | 40 pounds |
Annual rye grass | 1/4 pound | 10 pounds | |
Red clover | 1/4 pound | 10 pounds | |
Small grain mulch | March 1 to September 1 | 100 pounds (3 bales) | 2 tons 50 bales |
Fertilizer | March 1 to September 1 | 25 pounds of 10-10-10 equivalent | 1000 pounds 10-10-10 or equivalent |
For seedings made from September 1 to March I, add the following: | |||
Rye or wheat | 3 pounds | 2 bushels | |
Tall fescue | 1 pound | 40 pounds | |
(b) Seeding shall be done within two days after final grading or following seedbed preparation with a disc or other suitable equipment. On slope in land the final operation shall be done on the contour.
(c) Mulch shall be applied immediately after seeding and spread evenly over the entire area.
(d) Seed shall be applied uniformly with a cyclone seeder, drill, cultipacker seeder or hydro seeder.
(15) Storm sewer design.
(a) Where a storm sewer system is to be constructed within a roadway where curbs are installed, catch basins with curb inlets shall be required in accordance with the design specifications and standard drawings of the State of Ohio Department of Transportation, Division of Transportation, Bureau of Location and Design.
(b) Where a storm sewer system is being constructed and there are no curbs being installed or the storm sewer system is being installed away from the roadway, there shall be a drainage swale over the storm sewer system draining to the inlet basin. All such inlet basins shall be spaced according to these regulations and of the type specified by O.D.O.T. design criteria.
1. Computation of conduit design profile: computation of storm sewer lines shall be based on either Manning’s or Kutter’s Formula:
Manning’s Formula |
V = 1.486 R 2/3 S 1/2 n |
Kutter’s Formula |
V= 1.811 0.00281 (RS)1/2 n + 41.67 + S |
1 + n .00281 |
R 1/2 41.67 + S |
WITH Q = VA
Q= Discharge (cubic feet/second)
A = Area (square feet)
Q= Discharge (cubic feet/second)
A = Area (square feet)
WHERE S = Slope (feet/feet)
R = Hydraulic radius (feet)
N = Friction factor
V = Velocity (feet/second)
R = Hydraulic radius (feet)
N = Friction factor
V = Velocity (feet/second)
2. All storm sewers shall be designed with hydraulic slopes sufficient to give a mean velocity of not less than three feet per second, when flowing full, based on a value of n = 0.015 for sewers up to and including 27 inches; and n = 0.013 for sewers greater than 27 inches for clay and concrete pipe.
3. All catch basins and manholes shall be precast or cast-in-place concrete and shall be constructed in accordance with the design specifications of O.D.O.T.
4. In the case of sewers where velocities exceed 15 feet per second, special provisions shall be made to protect against erosion and displacement.
5. No storm sewer shall be less than 12 inches in diameter, and must be reinforced concrete or approved equal.
6. Single-family house spouting and footer drain connections shall not be less than four inches in diameter.
7. When storm sewers are increased in size, or when smaller sewers join larger ones, the invert of the larger should be lowered to maintain the same energy gradient, i.e., by placing the crown of both sewers at the same elevation.
8. In no case shall a larger pipe empty into a smaller one, even though the capacity of the smaller pipe is greater, unless prior approval is given by the Village Administrator.
(16) Appurtenances to storm drainage design.
(a) Storm sewers constructed within five feet, center to center, of sanitary sewers, shall have premium joints, i.e., meeting A.S.T.M. C433333 or C425. This criteria shall apply to mains as well as connections.
(b) Storm manhole joints shall be of the same type as its incoming sewer, premium joint sewer, A.S.T.M. C433 or C425, hence premium joint manhole A.S.T.M. C443.
(c) Manholes or catch basins shall be installed at all changes of size, grade and/or alignments.
(d) Maximum spacing for manholes and catch basins shall be 300 feet, as measured horizontally along the centerline of the pipe.
(e) The minimum cover for drainage pipes under pavement shall be 12 inches from the bottom of the pavement build-up to the crown of the pipe.
(f) The minimum internal diameter of manholes shall be 48 inches.
(g) Inlet catch basins shall be placed at all low points, and/or where required by the Village Administrator.
(h) All trench loading calculations shall be submitted to the Village Administrator. The type of pipe selected shall be of the class, material, construction and structure required to withstand the loads imposed.
(i) Headwalls and end walls shall be designed by a professional engineer registered in the state. Architectural treatment of headwalls and end walls may be required.
(j) The Village Administrator shall be consulted for design criteria for special manholes, non-circular sewers or special structures.
(k) The Village Administrator may require a special pipe material to be used for conditions such as alkalinity, excessive depth, polluted water or flat slopes.
(l) All drainage pipes shall be laid and maintained to the required lines and grades as shown on the plans. Manholes shall be installed with the main line unless otherwise approved in writing by the Village Administrator.
(m) All drainage pipes laid under pavement or within three feet the edge of the pavement shall be bedded, backfilled with granular material and mechanically tamped.
(B) Intersection/curb radius. The minimum curb radius shall be 25 feet to face of curb. An area of clear vision at street intersection shall be provided
(C) Driveways. The maximum grade on driveways shall not exceed 12%. Driveway pipe shall be reinforced concrete pipe or equal with a minimum diameter of 12 inches and a minimum length of 20 feet.
(D) Sidewalks. Sidewalks shall be composed of portland cement concrete, and shall conform to Item 608 of the current Construction and Material Specifications, State of Ohio, Department of Transportation. The outside edge of sidewalks will normally be placed within one foot of the street right- of-way line.
(E) Guard rail, seeding and the like. The necessity for guard rail, seeding, type backfill or other special conditions shall be determined with the assistance of the Village Administrator or his or her representative before completion of the construction plans.
(F) Cul-de-sac boulevard. The paved area within the circular space at the termination of cul-de-sacs shall have a minimum outside radius of 52 feet and an inside radius of 32 feet.
(G) Street name signs. The owner shall furnish and erect street name signs at all street intersections within the subdivision. The minimum requirements for the signs shall be 0.08 inch, reflectorized, six inches by 24 inches, with three-inch letters erected on two-inch galvanized, wrought-iron steel posts driven 30 inches into the ground and extending eight feet aboveground.
(H) Public utilities.
(1) Where public utilities, including telephone, gas, water, cable television, telecommunications, electric and sewers are available, provision shall be made for the installation of same before the street improvement is made, if feasible and possible. Laterals to gas, water, sewer, electric and telecommunication lines shall be sufficient in number to accommodate all possible users and shall extend to or beyond the street lines. Gas, water and sewer lines shall have sufficient capacity to provide service for all users and for the users that may in the future be added to the extension of the lines.
(2) All underground gas, telephone, cable television, telecommunication cable and electric lines shall be so designed and constructed to avoid conflict with any water and sewer lines, and the use of underground utilities is encouraged by the Commission. All trenches under the paved areas shall be backfilled with sand, gravel and screenings. (See division (A) above.)
(I) Stormwater runoff control.
(1) Purpose. This criteria shall serve as the minimum requirements for control of stormwater runoff leaving developments. These regulations require controlling of the discharge rate of runoff prior to its release to off-site land.
(2) Design frequency.
(a) The peak rate of runoff from an area after development shall not exceed the peak rate of runoff from the same area before development for all storms from a two-year to a 100-year frequency.
(b) Determine the total volume of runoff from a two-year frequency storm occurring on the area before and after development.
(c) Using the percent increase in volume of runoff in the development, pick the critical storm from the following table:
The percentage of increase in volume of runoff is equal to or greater than | and less than | The critical storm for discharge limitation shall be |
0 | 20 | 2 year |
20 | 50 | 5 year |
50 | 100 | 10 year |
100 | 250 | 25 year |
250 | 550 | 50 year |
500 | - | 100 year |
(d) The peak rate of runoff from the critical storm and all more frequent storms occurring on the development area shall not exceed the peak rate of runoff from a two-year frequency storm occurring on the same area under predevelopment conditions. Storms of less frequent occurrence than the critical storm of the 100-year storm shall have peak runoff rates from equivalent size storms under predevelopment conditions.
(e) Storage volume does not have to be provided for runoff from off-site upstream areas. Upstream runoff waters should be conveyed through the site in accordance with the current conditions.
(3) Final stormwater runoff control plan. A final stormwater runoff control plan shall be submitted to the Village Administrator for final approval. The final plan shall be developed in accordance with currently accepted policy and criteria. The final plan shall include all the engineering data required in division (I) hereof, and shall also include:
(a) The predevelopment rate of runoff and intensity for the various rainfall frequencies used in the analysis;
(b) The hydroiogic data of the tributary area, including time of concentration, intensity and runoff coefficients;
(c) The location of the proposed detention facility in relation to the tributary area;
(d) The inflow hydrographs for the tributary area prior to development for the various rainfall frequencies used in the analysis outlined in division (I)(2)hereof;
(e) The critical storm hydrograph based on the criteria outlined in division (I)(2) hereof;
(f) The storm hydrographs of the less frequent occurrences to check peak runoff rates;
(g) The maximum permissible release rate from the detention facility (i.e., outflow hydrograph);
(h) The storage volume required for the detention facility;
(i) The design of a facility for release of stored water and for bypassing excess flows of exceedingly rare rainfalls that cannot be accommodated by the storage facility;
(j) The design for complete and timely drainage of stored runoff by sufficient basin slope and/or alternate release mechanisms without causing secondary problems;
(k) Type of detention facility (rooftop, parking lot, basin and the like); and
(l) Safety precautions.
(4) Maintenance. The village shall assume responsibility for permanent maintenance of the major structures and facilities designed to control stormwater runoff. Major structures shall consist of, but not be limited to, sewer lines, catch basins and manholes. Maintenance of minor structures, above ground retention/detention structures, ditches and all other open watercourses, shall be the responsibility of the individual homeowners. Special covenants shall be written into the title of individual lots so the homeowners are aware that portions of their property shall be used for temporary water storage, and copies of covenants included with the final plat.
(5) Right of entry. Ownership and/or easements for the purpose of maintenance shall be granted to the village for access to all major stormwater control structures and facilities for which the village is assuming permanent maintenance responsibility.
(6) Financing. A “Perpetual Maintenance Agreement,” whereby all benefitting property owners of the allotment shall be assessed their proportionate share of the maintenance costs shall be provided.
(7) Parking area. When utilizing a parking area for detention facilities, the depth of water retained shall not exceed ten inches, and preferably six inches.
(J) Erosion and sedimentation control.
(1) Purpose. The following procedures have been specified to help minimize erosion and sedimentation problems encountered during the development process. Meeting the following standards and criteria does not relieve any person or firm from liability for erosion or sediment damage to another person’s property.
(2) Review procedures.
(a) All subdivisions shall be reviewed by the Village Administrator to see if the control plan shall be submitted for all subdivisions containing more than ten lots or the construction of a street.
(b) An erosion and sedimentation control plan shall be submitted for all subdivisions containing more than ten lots or the construction of a street.
(c) Subdivisions of less than ten lots which are a portion or phase of a larger proposed allotment shall submit a tentative erosion and sediment control plan for the entire allotment.
(3) General guidelines.
(a) When originating upgrade, runoff shall be intercepted or diverted away from the construction site so as to minimize the amount of flow over the construction site.
(b) Sediment basins, debris or desilting basins, silt fences, and/or silt traps, shall be installed and maintained to remove sediment of runoff waters from land undergoing construction.
(c) Terraces, diversions and/or grassed waterways should be installed and maintained as part of the water disposal system to further control water and sediment damage.
(d) Permanent vegetation, including the use of sod, and structures should be installed and maintained as soon as possible to help control water and sediment damage.
(e) Erosion control is to be installed prior to completion of construction. When work is being done during slow growing or dormant seasons, alternate and/or temporary solutions shall be effected.
(4) Control procedures.
(a) No disturbed land being developed shall have an average annual soil loss leaving the development area which exceeds 15 tons per acre for the first year, commencing from the time of initial earth disturbances, and four tons per acre for any other year as determined by using the Universal Soil Loss Equation (see U.S. Soil Conservation Service Handbook, Water Management and Sediment Control for Urbanizing Areas).
(b) When any construction could result in the sloughing, sliding or dumping of earth materials into a public waterway, the developer shall obtain a 404 permit from the Corps of Army Engineers.
(c) Drainage swales shall be constructed and seeded, sodded or protected with fabric material until vegetation if effective.
(d) Areas at the side, front and rear of new lots shall be seeded prior to construction even if final grading necessitates reseeding. Where lots may not be developed within 60 days, the entire area shall be seeded.
(e) New embankments shall be compacted and seeded within one week after placement. Drainage swales constructed shall be protected within one week after installation.
(f) Drainage swales and ditches where slopes exceed 4% shall have paved inverts. Outlets of storm sewers or paved ditches shall be provided with dumped rock and rip rap or, in problem areas, with stilling basins.
(g) The velocity of construction runoff water shall be decreased to retard erosion and give sediment or silt a chance to precipitate.
(h) Sediment laden runoff shall be trapped or filtered in temporary and permanent basins or by other acceptable methods.
(i) Drainage easements shall be provided where required for future or present drainage facilities event though installations are not made initially.
(j) Areas within the village adjacent or in developments which are used for agriculture shall not have vegetation removed to the property or ditch lines but shall maintain a ground cover buffer at least ten feet side. Drainage swales in areas adjacent to developments shall be maintained in vegetation especially when draining into developed allotments and streets.
(k) New construction and drainage swales shall be seeded within one week after installation.
(4) Plan contents. A plan developed to meet the requirements of this section shall contain information listed below explaining how the standards and criteria established in this section shall be met. Such plan may be incorporated as a part of other improvement plans or may be a separate document:
(a) The boundary lines and approximate acreage;
(b) Existing topography of the development area and of the land adjacent to it within 100 feet of the boundaries including the location of buildings, structures, utilities, water bodies, sewers, drainage facilities, vegetative cover, paved areas (streets, roads, sidewalks and the like), and other significant natural or human-made features;
(c) A general description and location of predominant soil types, all proposed earth disturbances including areas of excavation, grading, filling, installation of utilities, removal or destruction of topsoil and spreading of earth material and including a time schedule of each operation;
(d) Proposed use including present development and future utilization with detail on soil cover both vegetative and impervious;
(e) Provisions for erosion control during construction (temporary) and during the life of the development (permanent). Such provisions shall include a time schedule and sequence of operations with an estimated time exposure;
(f) Provisions for permanent stormwater management and the control of accelerated runoff to an adequate receiving outlet both on and off the development area;
(g) Design computations for measures of erosion and sediment pollution control structures;
(h) Provisions for maintenance of erosion and sediment control facilities;
(i) Title, scale, direction arrow, legend, date and name of person preparing plans and a statement giving any applicable engineering assumptions and calculations; and
(j) Name and address of the owner and/or person responsible for the developing the area.
(Ord. 09-2001, § 116.86, passed 3-5-2001)