[CC 1999 §23-61]
Unless specifically defined below, words or phrases in this Chapter shall be interpreted so as to give them the meaning they have in common usage and to give this Chapter its most reasonable application:
- The City of Chillicothe, Missouri.
- CITY ENGINEER
- The appointed City Engineer of public works or a delegated representative.
- The City Council of the City of Chillicothe, Missouri.
- DESIGN YEAR STORM
- The selected or established frequency or return period of rainfall time-duration for which drainage facilities are to be designed.
- DETENTION BASIN
- Any manmade area which serves as a means of controlling and storing storm water runoff.
- A person directing or participating in the direction of improvements on and/or to land including, but not limited to, the owner of the land, a general contractor or a commercial agent engaged for such activity.
- Any change of land use or improvement on any parcel of land.
- DRAINAGE BASIN (WATERSHEDS)
- The catchment area from which storm water is carried off by a watercourse or storm drainage system. The area served by a drainage system receiving storm and other surface-borne water. The boundaries of a drainage basin are a product of natural topography and drainage system configuration.
- DRAINAGE FACILITY
- A manmade structure or natural watercourse for the conveyance of storm water runoff. Examples are channels, pipes, ditches, swales, catch basins and street gutters.
- DWELLING UNIT
- One (1) or more rooms in a dwelling occupied or intended to be occupied as separate living quarters by a single family as defined herein.
- One (1) or more persons related by blood, marriage, adoption or occupying a dwelling unit as an individual housekeeping organization. A family may not include more than two (2) persons not related by blood, marriage, adoption or occupying a dwelling unit as an individual housekeeping organization.
- IMPERVIOUS SURFACE
- Surfaces on real property where infiltration of storm water into the earth has been virtually eliminated by the works of man.
- IMPROVED LAND
- Land having improvements that are impervious to, or alter the flow of, storm water within the limits of a platted, or otherwise distinguished, parcel of land.
- A structure on or other alteration of land.
- LOW-DENSITY RESIDENTIAL
- Individually platted lots containing two (2) or fewer dwelling units.
- Any person, firm, association, syndicate, partnership, corporation, trust or any other entity having legal title to or a sufficient proprietary interest to legally transfer real property. Proprietary interest shall include, but not be limited to, estate administration, trusteeship, guardianship and actions under a valid power of attorney. Proprietary interest shall not include an agency or a bare employment relation.
- A natural person, corporation, partnership or other entity.
- STORM DRAIN
- An improved storm drain is a closed conduit or paved open ditch for conducting collected storm water. An unimproved storm drain is an open ditch, natural or specifically constructed, for conveying collected storm water.
- STORM DRAINAGE DESIGN MANUAL
- A City manual for use by land developers in the design of storm drainage systems such as storm drains, culverts, streets, gutter flow hydraulics, natural drainage swales and storm inlets. The Storm Drainage Design Manual may include drainage policy to be followed, standard design methods, computation forms and City standards.
- STORM WATER DRAINAGE SYSTEM
- All drainage facilities used for collecting and conducting storm water to, through and from drainage areas to the points of final outlets including, but not limited to, any and all of the following:
- STORM WATER MANAGEMENT PLAN
- A City Master Plan describing the development of, and facilities required for, the storm water drainage system and additional improvements and actions necessary to the management of storm water drainage, entitled "City of Chillicothe, Missouri Storm Water Management Plan", as approved by the Council and from time to time amended.
- A relatively wide, shallow ditch around or between structures used to carry storm water runoff.
- UNIMPROVED LAND
- Land in its natural state.
- A stream, usually flowing in a particular direction (though it need not flow continuously in a definite channel), having a bed or banks and usually discharging into some other stream or body of water.
[CC 1999 §23-62]
No storm water drainage facility shall be constructed, altered or reconstructed without first obtaining a permit. All such construction shall comply with the general requirements and design procedures as set forth in this Chapter and the criteria of the Storm Drainage Design Manual. Storm water drainage facilities shall comport with the storm water management plan.
No clearing, grading, borrowing or filling of land shall be done without obtaining a permit from the City Engineer. All such work shall comport with the storm water management plan. No permit may be issued pursuant to this Subsection for clearing, grading, borrowing or filling of land on tracts greater than five (5) acres except in conjunction with a building permit issued in accordance with the provisions of Chapter 500. Every permit issued under this Subsection for clearing, grading, borrowing or filling of land not in conjunction with a building permit shall expire within one (1) year from the date of issuance.
The City Engineer shall promulgate rules and regulations governing the issuance of the permits required by this Section.
[Ord. No. 99-09 §1, 2-8-1999]
The following proposed fees for storm water drainage and grading projects be set as follows:
[CC 1999 §23-63]
Prior to the issuance by the City of a building permit for any low-density residential construction, the City Engineer's office will prepare the permit noting any special conditions to be met for storm drainage. This shall normally be accomplished within three (3) working days after receipt of the application.
Prior to the issuance by the City of a building permit for any other type of construction, the property owner, the developer or their agent shall have a detailed drainage plan approved by the City Engineer in accordance with this Chapter. The property owner, developer or their agent shall, at his/her own expense, submit necessary plans, designs and specifications to the City Engineer for review and approval.
Provisions of this Section for plan requirement may be waived by the City Engineer if, in his/her opinion, the amount of land disturbed and trees, shrubs, grass or vegetation is destroyed or removed or the construction, reconstruction, repair or alteration of any building does not materially alter or increase the flow of water.
[CC 1999 §23-64]
The City Engineer or his/her designated representative may periodically inspect the development site. Through such periodic inspections the City Engineer will review whether the drainage plan is properly implemented and that the improvements are maintained by the developer or owner until such time, if any, maintenance is taken over by the City.
[CC 1999 §23-65]
Whenever improvements to land are made, easements for the storm water drainage system shall be provided across private property. Easements through existing developments may be obtained as deemed necessary by the City Engineer. Drainage easements shall include access from a convenient public street. Maintenance of storm water sewers, lined drainage channels and related facilities located within public drainage easements shall be the responsibility of the owner of the project, unless the City, by ordinance, specifically agrees to undertake the maintenance. The City may undertake all maintenance activities, deemed necessary by the City Engineer, of natural watercourses and other unlined drainage channels located within public drainage easements; however, assumption of such maintenance activities does not relieve the property owner of the responsibility for normal maintenance including debris removal, cutting of vegetation, repair of erosion and removal of silt. Maintenance of storm water facilities located on private property and not within any public drainage easements shall be the responsibility of the property owners and shall include debris removal and cleaning, cutting of vegetation, repair of erosion, removal of silt and maintenance of structural facilities.
[CC 1999 §23-66]
The following shall be complied with in any development:
Storm water. Storm water shall be carried in enclosed storm conduits or open channels on the basis of criteria established in this Section, subject to final determination and approval of the City Engineer. It shall be understood that the requirements outlined in these standards are only minimum requirements.
Open channels. Open channels shall be located in drainage easements designed to provide a 50-year flood plain. The developer may be required to pave a channel if such paving is necessary to attain ultimate design capacity or to stabilize the embankments and channel flowline. If the channel extends between buildings, consideration must be given to provide adequate protective measures such as paving the channel invert and side slopes, bank protection or fencing. Open channels in residential areas shall generally be located along the rear or side lot lines.
Side line drainage. Storm drainage along the side lot lines of residential property for pipe sizes through twenty-four (24) inch diameter shall be in conduit for the full length of the side lot line or the nearest natural drainage way of a larger tributary stream. Discharge protection shall be provided to minimize erosion and disperse flow.
Storm drainage along the side lot lines of residential property for pipe sizes above twenty-four (24) through forty-eight (48) inch diameter shall be in conduit to a point thirty (30) feet to the rear of the front building line or ten (10) feet beyond the rear line of the structure, whichever is greater. Extension of the system shall then be continued from this point the full length of the side lot line or to the nearest natural drainage way of a larger tributary stream with a stable ditch section.
Storm drainage along the side lot line of residential property for pipe sizes above forty-eight (48) inch diameter shall be designed with a stable ditch section.
In all instances, a surface swale shall be provided over the drainage system to contain at least a 50-year storm.
Under roadways. Where culverts are placed under roadways, they shall extend to the limits of right-of-way or the toe of the roadway embankment if that distance is greater and proper hydraulic structures shall be provided for dissipation of velocity to prevent erosion. Embankments shall be protected by riprapping or some other approved method to prevent erosion against a 50-year frequency storm.
Future connections. Pipe drains or culverts constructed to intercept the flow of ditches or channels, which may be enclosed in a conduit at a future time, shall be laid at the required depth to permit their extension at the same required depth.
Intersections. Curb inlets shall be installed at or near intersections where they are deemed necessary for the safety of pedestrian and vehicular traffic. Curb inlets shall be placed so as to intercept the storm water before it reaches the crosswalks and no curb inlet shall be located within a crosswalk. The above is particularly important in commercially zoned areas and other areas of high pedestrian traffic and is considered desirable in all other areas.
Drainage onto sidewalks. Tributary areas where sidewalks exist or are proposed, and which drains across a public sidewalk, must not exceed three thousand (3,000) square feet of impervious area, including roofs discharging upon paved areas, or nine thousand (9,000) square feet of sodded areas or a proportional amount for a combination of such areas. Paved, roofed or other impervious areas exceeding three thousand (3,000) square feet shall be provided with drains for discharge into storm conduits, channels or street gutters.
Downspouts. Downspouts shall be connected to the drainage system when possible by a method approved by the City Engineer. Where no system exists, they shall not be directed to adjacent lots or structures. They shall not be discharged directly onto sidewalks or entrance ways.
Flow toward streets. Any concentration of surface flow in excess of two (2) cubic feet per second (cfs) for the 10-year frequency rain shall be intercepted before reaching the street right-of-way and shall be carried by an enclosed storm drain to connect with a drainage structure at the low point in the street right-of-way or to discharge to a watercourse.
Parking lots and garages. Adequate provisions shall be made for the disposal of storm water from parking lots and garages. Plans shall be submitted for approval to the City Engineer to ensure measures are taken to limit the flow of water onto adjoining property to adjacent sidewalks or streets in a quantity that would be detrimental to or inconvenient to persons using the streets or sidewalks.
Detention basin. Detention basins shall be designed using methods acceptable to the City Engineer. Detention basins shall be designed by a registered professional engineer or architect, authorized to practice in the State of Missouri, who shall provide a statement as to the characteristics of the achieved storm water flow restrictions.
Easements. The minimum width of easements for storm water drainage shall be fifteen (15) feet. Where a storm drain consists of a closed conduit, the width shall be the greater of fifteen (15) feet or the sum of the conduit diameter and twice the cover depth over the conduit.
[CC 1999 §23-67]
Drainage plans will be satisfactory to the City Engineer and will normally include the following:
A boundary survey for unplatted parcels by a licensed surveyor.
Details defining the alignment, boundary and acreage of any natural drainage course, drainage facility or subdrainage area on the land in question.
Detail drawings of profiles and specifications for construction of channels, conduits, detention ponds, culverts, bridges and all other drainage facilities reasonably necessary to ensure that flood and storm waters, including drainage from other lands which will contribute runoff to the subject property, will be adequately drained, stored or otherwise controlled. Included in the drainage plan shall be a schedule containing the estimated dates of completion of construction for all storm water drainage facilities shown on the drainage plan. If the drainage plan is approved and the building permit issued, the applicant shall comply with said schedule.
Specific plan details shall include the following:
Plan sizes shall be twenty-four (24) inch by thirty-six (36) inch or twenty-two (22) inch by thirty-four (24) inch plan and profile. Minimum horizontal scale of one (1) inch equals fifty (50) feet and vertical scale of one (1) inch equals ten (10) feet.
The cover sheet key map of the entire project to scale one (1) inch equals two hundred (200) feet showing storm drains and facilities, both existing and to be constructed.
Plans and profiles of each storm drain, showing location, size, design flow, flowline elevations, gradients and materials, boring information and rock elevations along the proposed storm drain anywhere applicable; location, depths and sizes of adjacent or crossing wastewater lines and utilities; and special construction requirements such as concrete cradle or encasement, backfill, size and class of pipe, etc.
All elevations shall be based upon U.S.G.S. datum with location noted of benchmark used.
Typical cross sections of swales, ditches or channels.
Details of special structures, culverts, transitions, headwalls, aprons and junction chambers, all adequately detailed and dimensioned including placement of steel. Unless otherwise indicated, standard City structures are assumed where applicable.
For all detention basins, if any, a plot of storage volumes with corresponding water surface elevations and of the basin outflow rates for those water surface elevations.
The cover sheet will contain the following certified statement by a registered professional engineer or architect:
A drainage area map showing topography shall be furnished for the development. For low-density residential development, this shall be in conformance with platting procedures. For any other development a drainage area map showing topography shall be furnished for the development. The scale of such maps to be as follows:
Design computations. The engineer or architect shall have detailed design computations available to support his/her design and shall submit them to, or review them with, the City Engineer.
[CC 1999 §23-68]
The design procedures stipulated in the latest edition of the Storm Drainage Design Manual shall be followed insofar as they are applicable. Written justification for all deviations must be prepared and submitted in accordance with the variance procedures set forth in this Chapter.
All drainage plans shall meet the design requirements of any City ordinance regulating floodwater control and subdivision of land.
[CC 1999 §23-69]
Location Of Structures. In addition to any other requirements set forth by ordinance for construction in designated flood hazard areas, the following restrictions for construction adjacent to all watercourses and other drainage facilities shall apply:
No house or building and no other structure which is not floodproofed shall be constructed within thirty (30) feet of the top of the bank of a watercourse or other drainage facility nor shall any such structure be constructed with openings at an elevation below four (4) feet above the highest bank of a watercourse or top of other drainage facilities which traverse or are adjacent to the parcel being developed.
The City Engineer may vary the above requirements upon visiting the building site for low-density residential construction or reviewing plans for any other construction should such revisions not diminish the overall intent of this Chapter.
Existing Storm Drains. No cuts shall be made nor fill deposited over existing storm drains nor shall existing storm drains be altered without the approval of the City Engineer.
[CC 1999 §23-70]
Conformance With Storm Water Management Plan. Drainage plans submitted by developers must be developed in conformance with the storm water management plan in effect at the time of the submission.
Restriction Of Runoff. The City may require that storm drainage systems for tributary areas upstream of existing storm drainage facilities include on-site storm water detention facilities limiting the peak discharge to that which would have occurred for the existing land use type prior to a zoning change or prior to development of the area. The City may waive such requirements for detention facilities when the developer makes satisfactory arrangements to improve or provide a downstream drainage system of adequate hydraulic capacity for peak rates of discharge to the system, including discharge from the developer's site, to a point downstream where the rate of total runoff from the site is ten percent (10%) or less of the total runoff rate conveyed by the downstream system measured at the time of system peak rate. The City may, at its option, also permit downstream system improvements and detention combinations that provide the same level of control.
Storm Water Management Plan Facilities. Drainage plans and facilities constructed by developers for developments encompassing more than forty-three thousand five hundred sixty (43,560) square feet in total area, including areas not directly subject to improvements, must include any improvements not previously constructed, which are planned as part of the storm water drainage system on the affected property pursuant to the storm water management plan. For purposes of this paragraph, the storm water management plan in effect at the time of submission of the drainage plan shall govern. Also for purposes of this paragraph, the affected property shall include any adjacent property under common ownership with, and within one hundred (100) feet of the limits of, the parcel of property being developed. Where the cost of such storm water related improvements exceeds ten percent (10%) of the total cost of the development, excluding the cost of land, the developer may petition for City participation in financing and/or contribution to the funding of the improvements.
Alternative Improvements. In reviewing petitions for variances from the requirements of this Section, the City will consider alternative improvements or types of improvements proposed by developers which the City deems to be equivalent for the purposes of storm water management.
[CC 1999 §23-71]
No person shall damage or discharge or place any substance into the drainage system which will or may cause obstruction to flow or other interference with the operation of the storm water drainage system. Any person violating this Section for damaging the storm water drainage system shall be liable to the City for all expense, loss or damage incurred by the City due to such violation or damage, in addition to any other penalties set forth herein.
[CC 1999 §23-72]
If it is determined that development is not proceeding in accordance with the approved drainage plan, the City Engineer shall issue a written stop work order to the developer detailing the nature and location of the non-compliance and specifying what remedial work is necessary to bring the project into compliance. The developer shall immediately stop work on all aspects of the development except the required remedial action, which shall begin. The developer shall complete the remedial work within a reasonable time after receipt of said order. Upon satisfactory completion of the remedial work, the City Engineer shall issue a notice of compliance and the development may proceed.
[CC 1999 §23-73]
General Provisions. Where undue hardship or practical difficulties may result from strict compliance with this Chapter, the developer may petition for a variance. The City Engineer may recommend, and the Council may approve, variances so that substantial justice may be done and the public interest secured; provided that any such variance shall not have the effect of nullifying the intent and purpose of this Chapter; and further provided that the Council shall not grant variances unless they find and determine that:
The granting of the variance will not be detrimental to the public safety, health or welfare or injurious to other property or improvements.
The conditions upon which the request for a variance is based are unique to the property for which the variance is sought, are not applicable generally to other property and are not self-imposed.
Because of the particular physical surroundings, shape or topographical conditions of the specific property involved, a particular hardship to the owner would result, as distinguished from a mere inconvenience, if this Chapter was strictly interpreted and carried out.
Conditions. In recommending variances and exceptions, the City Engineer may recommend and the Council may require such conditions as will, in the judgment of each, secure substantially the objectives of the standards or requirements of this Chapter.
Procedures. A petition for a variance shall be submitted at the time of filing for a preliminary plat or for application for building permit. The petition shall state fully the grounds for the request and all facts relied upon by the petitioner.
[CC 1999 §23-74]
The provisions of this Chapter shall be administered and enforced by the City Engineer. The City Engineer shall prescribe forms for attainment of the purposes of this Chapter and for the proper enforcement thereof. The City Engineer may delegate the administration of this Chapter or any part thereof, subject to limitations of the ordinances of the City, to duly qualified employees, deputies or agents of the City.
[CC 1999 §23-75]
Floods from storm water runoff may occur which exceed the capacity of storm water drainage facilities constructed and maintained under this Chapter. This Chapter does not guarantee that property will always be free from storm water flooding or flood damage. This Chapter shall not create a liability on the part of, or cause of action against, the City or any officer or employee thereof for any flood damage. Neither does this Chapter purport to reduce the need or the necessity for obtaining flood insurance.
[CC 1999 §23-76; Ord. No. 98-150, 11-9-1998]
Conditions. Regulation of storm water drainage and the attachment of reasonable conditions thereto is an exercise of the valid Police power delegated by the State of Missouri to the City. Property owners have the duty of compliance with reasonable policies, regulations, standards and conditions established by the City for design, construction, improvement and restrictive use of the land so as to conform to the physical and economical development of the City and to promote the health, safety and general welfare of the community at large.
Interpretation. The provisions of this Chapter shall be the minimum requirements for the protection of the public health, safety and general welfare.
Conflict. Conflict with public and private provisions:
Public provisions. Where any provision of this Chapter imposes restrictions different from those imposed by any other law or regulation, whichever is more restrictive or imposes a higher standard shall control.
Private provisions. This Chapter is not intended to abrogate any easement, covenant or any other private agreement or restriction; provided that where the provisions of this Chapter are more restrictive or impose higher standards or regulations than such easement, covenant or other private agreement or restriction, the requirements of this Chapter shall govern.