[Ord. No. 1677 §2, 9-22-1999]
The provisions of this Chapter shall constitute and be known as the "Storm Water Management Ordinance" for the City of Richmond, Missouri, hereby called the "City".
The purpose of this Chapter is to protect, maintain and enhance the public health, safety and general welfare by establishing the minimum requirements and procedures to control the adverse effects of increased storm water runoff associated with both future land development and existing developed land within the City. Proper management of storm water runoff will minimize damage to public and private property, ensure a functional drainage system, reduce the effects of development on land and stream channel erosion, assist on the attainment and maintenance of water quality standards, enhance the local government associated with the drainage system, reduce local flooding, maintain as nearly as possible the pre-developed runoff characteristics of the area and facilitate economic development while mitigating associated flooding and drainage impacts.
The application of this Chapter and the provisions expressed herein shall be the minimum storm water management requirements and shall not be deemed a limitation or repeal of any other powers granted by State Statute. In addition, if site characteristics indicate that complying with these minimum requirements will not provide adequate designs or protection for local property or residents, it is the designer's responsibility to exceed the minimum requirements as necessary. Should the requirement contained in this Chapter and guide not be followed, then APWA Section 5600 Development Criteria for storm drainage systems and facilities shall apply. The Community Development Director shall be responsible for the coordination and enforcement of the provisions of this Chapter.
If at some time in the future NPDES storm water regulations are applied to Richmond, then future development will be required to meet the criteria required by NPDES storm water regulations and those requirements shall be incorporated into this Chapter.
[Ord. No. 1677 §3, 9-22-1999]
For the purposes of this Chapter, the following terms, phrases and words and their derivatives shall have the meaning given herein:
- AS-BUILT PLAN
- A set of engineering or site drawings that delineate the specific permitted storm water management facility as actually constructed.
- BEST MANAGEMENT PRACTICES
- A wide range of management procedures, schedules of activities, prohibitions on practices and other management practices which have been demonstrated to effectively control the quality and/or quantity of storm water runoff and which are compatible with the planned land use.
- The City of Richmond, Missouri.
- CITY ADMINISTRATOR
- The official responsible for the administration of the City or his/her duly authorized representative.
- COMMUNITY DEVELOPMENT DEPARTMENT
- The Department of Community Development established by the Council of the City of Richmond, Missouri.
- COMMUNITY DEVELOPMENT DIRECTOR
- The individual designated by the City Administrator to direct the operations of the Community Development Department.
- CROSS-DRAIN CULVERT
- A culvert located under a roadway.
- DESIGN REPORT
- The report that accompanies the storm water management plan and includes data used for engineering analysis, results of all analysis, design and analysis calculations (including results obtained from computer programs), and other engineering data that would assist the City in evaluating proposed storm water management facilities.
- A professional engineer, architect or land surveyor licensed in the State of Missouri who prepares plans and studies required by this Chapter.
- DETENTION STRUCTURE
- A permanent storm water management structure whose primary purpose is to temporarily store storm water runoff and release the stored runoff at controlled rates.
- DEVELOP LAND
- To change the runoff characteristics of a parcel of land in conjunction with residential, commercial, industrial or institutional construction or alteration.
- DEVELOPED LAND USE CONDITIONS
- The land use conditions according to the current, official Zoning Map adopted by the City of Richmond, Missouri.
- Any of the following actions undertaken by a public or private individual or entity:
- 1. The division of a lot, tract or parcel of land into two (2) or more lots, plots, sites, tracts, parcels or other divisions by plat or deed; or
- 2. Any land change, including without limitation, clearing, tree removal, grubbing, stripping, dredging, grading, excavating, transporting and filling of land.
- A grant or reservation by the owner of land for the use of such land by others for a specific purpose and which must be included in the conveyance of land affected by such easement.
- The wearing away of land surface by the action of wind, water, gravity, ice or any combination of those forces.
- EROSION AND SEDIMENT CONTROL
- The control of solid material, both mineral and organic, during a land disturbing activity to prevent its transport out of the disturbed area by means of air, water, gravity or ice.
- EXISTING LAND USE CONDITIONS
- The land use conditions existing at the time of the most recent official aerial photograph available from the City.
- Excavating, filling (including hydraulic fill) or stockpiling of earth material or any combination thereof, including the land in its excavated or filled condition.
- The condition of being impenetrable by water.
- The decree to which a site is impervious.
- The passage or movement of water through the soil profile.
- INTERIOR CULVERT
- A culvert that is not located under a roadway.
- LAND DISTURBING ACTIVITY
- Any use of land by any person that results in a change in the natural cover or topography that may cause erosion and contribute to sediment and alter the quality and/or quantity of storm water runoff.
- Any action necessary to preserve storm water management facilities in proper working condition in order to serve the intended purposes set forth in Article I of this Chapter and to prevent structural failure of such facilities. Maintenance shall not include actions taken solely for the purpose of enhancing the aesthetic aspects associated with storm water management facilities.
- NATURAL WATERWAYS
- Waterways that are part of the natural topography. They usually maintain a continuous or seasonal flow during the year and are characterized as being irregular in cross-section with a meandering course. Construction channels such as drainage ditches shall not be considered natural waterways.
- A material e.g., natural rock, riprap, concrete, plastic, etc., that will not experience surface wear due to natural forces of wind, water, ice, gravity or a combination of those forces.
- NON-POINT SOURCE POLLUTION
- Pollution contained in storm water runoff from ill defined, diffused sources.
- OFFICIAL MAP
- The Zoning Map adopted by the City Council showing the zoning districts, streets, highways and parts theretofore laid out, adopted and established by law and any amendments thereto resulting and adopted by the City Council or additions thereto resulting from the approval of subdivision plats and the subsequent filing of such approved plats.
- ONE HUNDRED YEAR FREQUENCY STORM
- A storm that is capable of producing rainfall expected to be equaled or exceeded on the average of one (1) in one hundred (100) years. It also may be expressed as an exceedance probability with a one percent (1%) chance of being equaled or exceeded in any given year.
- ON-SITE STORM WATER MANAGEMENT
- The design and construction of a facility necessary to control storm water runoff within and for single development.
- 1. The person who has or represents those having financial or operational control over the land disturbing activity; and/or
- 2. The landowner or person in possession or control of the land who directly or indirectly allowed the land disturbing activity or has benefited from it or who has failed to comply with any provision of this Chapter.
- POST DEVELOPMENT CONDITIONS
- The conditions which exist following the completion of the land disturbing activity in terms of topography, vegetation, land use and rate, volume or direction of storm water runoff.
- PRE-DEVELOPMENT CONDITIONS
- Those land use conditions that existed prior to the initiation of the land disturbing activity in terms of topography, vegetation, land use and rate, volume or direction of storm water runoff.
- PRELIMINARY PLAT
- The preliminary plat of residential or commercial subdivision submitted pursuant to the City's subdivision regulations.
- RECORD SURVEY
- A final field survey which locates the visible surface features of a constructed storm water facility on the ground, but without locating non-visible or subsurface features such as the actual route and elevation of buried pipe.
- REGIONAL STORM WATER MANAGEMENT
- The design and construction of a facility necessary to control storm water runoff within or outside a development and for one (1) or more developments.
- REGISTERED CIVIL ENGINEER
- A civil engineer properly registered and licensed in the State of Missouri.
- REGISTERED LAND SURVEYOR
- A land surveyor properly registered and licensed in the State of Missouri.
- REGISTERED LANDSCAPE ARCHITECT
- A landscape architect properly registered and licensed in the State of Missouri.
- RESPONSIBLE PERSON
- Any foreman, superintendent or similar individual who is the on-site person in charge of land disturbing activities.
- RETENTION STRUCTURE
- A permanent structure whose primary purpose is to permanently store a given volume of storm water runoff. Release of the given volume is by infiltration and/or evaporation.
- Solid particulate matter, both mineral and organic, that has been or is being transported by water, air, ice or gravity from its site of origin.
- The installation of vegetative or structural measures to establish a soil cover to reduce soil erosion by storm water runoff, wind, ice and gravity.
- STAGE WORK OR STAGE CONSTRUCTION
- A plan for the staged construction of storm water facilities where portions of the facilities will be constructed as different stages of the proposed development are started or completed.
- STORM WATER CONCEPT PLAN
- The overall proposal for a storm drainage system, including storm water management structures, and supporting documentation as specified in the Storm Water Management Design Guide for each proposed private or public development to the extent permitted by law. Also included are the supporting engineering calculations and results of any computer analysis, if necessary.
- STORM WATER MANAGEMENT DESIGN GUIDE
- The manual of design, performance and review criteria for storm water management practices prepared under the direction of the City or contacted professional. Copies of this manual can be obtained from the City.
- STORM WATER MANAGEMENT FACILITIES
- Those structures and facilities that are designed for the collection, conveyance, storage, treatment and disposal of storm water runoff into and through the drainage system.
- STORM WATER MANAGEMENT PLAN
- The set of drawings and other documents that comprise all of the information and specifications for the drainage systems, structure, concepts and techniques that will be used to control storm water as required by this Chapter and the Storm Water Management Design Guide. Also included are the supporting engineering calculations and results of any computer analysis.
- STORM WATER MANAGEMENT QUALITATIVE CONTROL
- A system of vegetative, structural or other measures that reduce or eliminate pollutants that might otherwise be carried by storm water runoff.
- STORM WATER RUNOFF
- The direct response of a watershed to precipitation and includes the surface and subsurface runoff that enters a ditch, stream, storm drain or other concentrated flow during and following the precipitation.
- The division of land into two (2) or more lots or parcels. The term "subdivision" shall also include all resubdivisions of land or lots.
- SUBDIVISION, MINOR
- The division of land into two (2) but not more than four (4) lots which does not include any new streets, improvements, easements or rights-of-way; a division of land in which each parcel is five (5) acres or more in area and does not include any new streets, improvements, easements or rights-of-way, or other provisions for public areas and facilities; the division of land held in a bona fide partnership in existence for two (2) or more years upon dissolution thereof; a division of land among the immediate members of a family for personal use which does not include any new streets, improvements, easements or rights-of-way.
- 1. Does not include any new streets, easements, right-of-way, rights of ingress or egress but shall include an approved sewer and water system.
- 2. Does not include a provision for a public area or public facility.
- 3. Conforms to the minimum lot area and other requirements contained in the Zoning Code.
- 4. Conveys the right-of-way necessary for road widening and maintenance of City roads where the granting of such right-of-way can be given without undue hardship.
- A structure measured with a lining of grass, riprap or other materials which can function as a detention structure and convey storm water runoff without causing erosion.
- TEN-YEAR FREQUENCY STORM
- A storm that is capable of producing rainfall expected to be equaled or exceeded on the average of once in ten (10) years. It may also be expressed as an exceedance probability with a ten percent (10%) chance of being equaled or exceeded in any given year.
- TWENTY-FIVE YEAR FREQUENCY STORM
- A storm that is capable of producing rainfall expected to be equaled or exceeded on the average of once in twenty-five (25) years. It may also be expressed as an exceedance probability with a four percent (4%) chance of being equaled or exceeded in any given year.
- TWO-YEAR FREQUENCY STORM
- A storm that is capable of producing rainfall expected to be equaled or exceeded on the average of once in two (2) years. It may also be expressed as an exceedance probability with a fifty percent (50%) chance of being equaled or exceeded in any given year.
- The modification by the City Council of the minimum storm water management requirements for specific circumstances where the strict adherence of the requirements would result in unnecessary hardship and not fulfill the intent of this Chapter.
- The relinquishment from storm water management requirements by the City Council for a specific land disturbing activity on a case-by-case review basis.
- WATER QUALITY
- Those characteristics of storm water runoff from a land disturbing activity that relates to the physical, chemical, biological or radiological integrity of water.
- WATER QUANTITY
- Those characteristics of storm water runoff that relate to the rate and volume of the storm water runoff to downstream areas resulting from land disturbing activities.
- The drainage area contributing storm water runoff to a single point.
[Ord. No. 2081, 5-14-2008]
All storm water ditches, creeks, streams or waterways are to be maintained by the adjoining property owners and shall be kept free from leaves, brush and debris to maintain a continuous flow of water except where such ditches, creeks and waterways are designated as part of the City critical storm water management system by the City of Richmond.
[Ord. No. 1677 §4, 9-22-1999]
No person shall develop any land without having provided for appropriate storm water management measures that control or manage runoff in compliance with this Chapter, unless exempted in Section 412.040.
[Ord. No. 1677 §5, 9-22-1999]
The following development activities are exempt from the provisions of this Chapter and the requirements of providing storm water management measures:
Land disturbing activities on agricultural land for production of plants and animals useful to man.
Land disturbing activities undertaken on forest land for the production and harvesting of timber and timber products.
Construction or improvement resulting in less than a fifty percent (50%) increase in square footage of single-family residences or their accessory buildings.
[Ord. No. 1677 §6, 9-22-1999]
To assist in the design and evaluation of storm water management facilities in the City, a Storm Water Management Design Guide has been developed. Example design procedures and criteria are presented for conducting hydrologic and hydraulic evaluations. Although the intention of the guide is to establish uniform design practices, it neither replaces the need for engineering judgment nor precludes the use of information not presented. Other accepted engineering procedures may be used to conduct hydrologic and hydraulic studies if approved by the City.
If individual lots or sections in a residential/commercial subdivision are being developed by different property owners, all land disturbing activities related to the residential/commercial subdivision shall be covered by the approved storm water management plan for the residential/commercial subdivision. Individual lot owners or developers shall sign a certificate of compliance that all activities on that lot will be carried out in accordance with the approved storm water management plan for the residential/commercial subdivision on file in the office of the Community Development Director.
Residential/commercial subdivisions which were approved for construction by the City Council prior to the effective date of these regulations are exempt from these requirements. Development of new phases of existing subdivisions which were not previously approved shall comply with the provisions of these regulations.
For residential land disturbing activities involving three (3) acres or less of actual land disturbance which are not part of a larger common plan of development or sale, the person responsible for the land disturbing activity shall submit a simplified storm water management plan to the Community Development Department meeting the requirements listed below. This plan does not require approval by the City and does not require preparation of certification by the designers specified in Section 412.150. All commercial developments regardless of size must conform to Sections 412.060 through 412.150 unless a waiver is granted by the City.
A narrative description of the storm water management facilities to be used.
A general description of topographic and soil conditions of the development site.
A general description of adjacent property and a description of existing structures, buildings and other fixed improvements located on surrounding properties.
A sketch plan to accompany the narrative which shall contain:
A site location drawing of the proposed project, indicating the location of the proposed project in relation to roadways, jurisdictional boundaries, streams and rivers;
The boundary lines of the site on which the work is to be performed;
All areas within the site which will be included in the land disturbing activities shall be identified and the total disturbed area calculated;
A topographic map of the site;
Anticipated starting and completion dates of the various stages of land disturbing activities and the expected date the final stabilization will be completed; and
The location of temporary and permanent vegetative and structural storm water management control measures.
Storm water management plans shall contain certification by the person responsible for the land disturbing activity that the land disturbing activity will be accomplished pursuant to the plan on file in the office of the Community Development Director.
Storm water management plans shall contain certification by the person responsible for the land disturbing activity of the right of City to conduct on-site inspections on file in the office of the Community Development Director.
[Ord. No. 1677 §7, 9-22-1999]
A storm water concept plan for development shall be submitted for review by the Community Development Director prior to submission of the storm water management plan and construction plans for the entire development, or any portion thereof. The storm water concept plan must identify the location and type of facilities to be constructed in sufficient detail to accurately estimate construction cost and enable the Community Development Department to determine if a storm water management plan is needed. If they determine a final storm water management plan is needed, the concept plan then becomes the basis for the storm water management plan for this development.
All preliminary plats of the development shall be consistent with the storm water concept plan required in Subsection (A) above.
Upon approval of the concept plan by the Community Development Department the applicant shall submit a final storm water management plan (as part of the construction plans) to the City Council for review and approval.
Should any storm water management plan involve any storm water management facilities or land to be dedicated to public use, the same information shall also be submitted for review to the department having jurisdiction over the land or other appropriate departments or agencies prior to submission to the City Council for review and approval. The final storm water management plan shall serve as the basis for all subsequent construction.
If disapproved by the City Council, the storm water management plan may be reviewed with the designer, where it will either be changed, modified or resubmitted. If rejected, changes, additional analysis or other information needed to approve the next submittal of the concept plan shall be identified by the City Council. After the receipt of the revised storm water management plan, the City Council shall issue a decision approving, rejecting or conditionally approving the plan with modification.
[Ord. No. 1677 §8, 9-22-1999]
No site grading permit shall be issued or modified without the following:
Right of entry for emergency maintenance if necessary. (See Exhibits E and F which are on file in the office of the Community Development Director.)
Right of entry for inspections. (See Exhibits E and F which are on file in the office of the Community Development Director.)
Any off-site easement needed.
An approved storm water concept plan or storm water management plan, as appropriate.
An approved storm water ownership and maintenance plan.
The approved storm water management plan shall contain certification by the applicant that all land clearing, construction, development and drainage will be done according to the storm water management plan or previously approved revisions. Any and all site grading permits may be revoked at any time if the construction of storm water management facilities is not in strict accordance with approved plans. (See Exhibit C which is on file in the office of the Community Development Director.)
In addition to the plans and permits required from the City, applicants shall obtain all State and Federal permits required for the proposed development.
[Ord. No. 1677 §9, 9-22-1999]
A list of fees for plan review and other fees associated with this Chapter can be obtained from the Community Development Department.
[Ord. No. 1677 §10, 9-22-1999]
A site grading permit may be suspended or revoked if one (1) or more of the following violations have been committed:
Violation(s) of the conditions of the storm water management plan as approved.
Construction not in accordance with the approved plans.
Non-compliance with correction notice(s). (See Exhibit H which is on file in the office of the Community Development Director.)
The existence of an immediate danger in a downstream area in the judgment of the Community Development Director or his/her designee.
If one (1) or more of these conditions are found, a written notice of violation(s) shall be served upon the owner or authorized representative and an immediate stop work order may be issued. The notice shall set forth the measures necessary to achieve compliance with the plan. Correction of these violations must be started immediately or the owner shall be deemed in violation of this Chapter.
[Ord. No. 1677 §11, 9-22-1999]
The following standards shall constitute minimum runoff control requirements:
The minimum storm water control requirements shall provide management measures necessary to accomplish the following:
Install storm water management facilities to limit the two (2) year and ten (10) year developed peak discharge rates. The design of these facilities shall be based on procedures contained in the Storm Water Management Design Guide or procedures approved by the Director of Public Works. At a minimum, enclosed systems must incorporate the APWA 5600 requirement to convey the ten (10) year event (larger as appropriate for street/roadway crossings) and all new drainage systems must prove either in-pipe, in-channel, or at least an adequate overload flow patch for the one hundred (100) year event that does not encroach on existing structures or must be at least fifty (50) feet setback from any proposed structures. The two (2) year and ten (10) year design storms cover the range of normal flooding. Structures must be analyzed for both. The twenty-five (25) year, fifty (50) or one hundred (100) year storm events shall be used for structures under local, State and Federal roadways respectively.
There shall be a minimum setback of fifty (50) feet from the defined one hundred (100) year flowpath for all new construction.
The requirements or portions thereof of Subsections (1) and (2) above may be waived by the City Council if it can be shown by the detailed engineering calculations and analysis which are acceptable to the City that one (1) of the following exists:
The installation of storm water management facilities would have insignificant effects on reducing downstream flood peaks;
Storm water management facilities are not needed to protect downstream developments and the downstream drainage system has sufficient capacity to receive any increase in runoff for the design storm;
It is not necessary to install storm water management facilities to control developed peak discharge rates at the exit to a proposed development and installing such facilities would increase flood peaks at some downstream locations; or
The Community Development Department determines that storm water management facilities are not needed to control developed peak discharge rates and installing such facilities would not be in the best interest of the City.
The requirements or portions thereof of Subsection (1) above may not be waived if the City determines that not controlling downstream flood peaks would increase known flooding problems or exceed the capacity of the downstream drainage system.
A waiver shall only be granted after a written request is submitted to the City Administrator through the Community Development Department by the applicant containing descriptions, drawings and any other information that is necessary to evaluate the proposed land disturbing activity. A separate written waiver request shall be required if there are subsequent additions, extensions or modifications which would alter the approved storm water runoff characteristics to a land disturbing activity receiving a waiver. The City will conduct a review of the request for a waiver.
Discharge velocities shall be reduced to provide a non-erosive velocity flow from a structure, channel or other control measure or the velocity of the ten (10) year design storm runoff in the receiving waterway prior to the land disturbing activity, whichever is greater.
For all storm water management facilities, a hydrologic-hydraulic study shall be done showing how the drainage system will function with and without the proposed facilities. For such studies, the following land use conditions shall be used. Existing land use data shall be taken from the most recent aerial photography and field checked and updated.
For the design of the facility outlet structure, use developed land use conditions for the area within the proposed development and existing land use conditions for upstream areas draining to the facility.
For any analysis of flood flows downstream from the proposed facility using existing land use conditions for all downstream areas.
All storm water management facilities emergency spillways shall be checked using the one hundred (100) year storm and routing flows through the facility and emergency spillways. For this analysis, developed land use conditions shall be used for all areas within the analysis.
If accepted for City maintenance, the effects of existing upstream detention facilities can be considered in the hydrologic-hydraulic study.
[Ord. No. 1677 §12, 9-22-1999]
Storm water management facilities may include both structural and non-structural elements. Natural swales and other natural runoff conduits shall be retained where practicable.
When additional storm water management facilities are required to satisfy the minimum control requirements, the following measures are examples of what may be used:
Where detention and retention structures are used, designs which consolidate these facilities into a limited number of large structures will be preferred over designs which utilize a large number of small structures.
Storm water management plans may be rejected by the City if they incorporate structures and facilities that will demand considerable maintenance, will be difficult to maintain or utilize numerous small structures if other alternatives are physically possible.
The drainage system and all storm water management structures within the City (including both public and private portions) will be designed to the same engineering and technical criteria and standards. The City's review will be the same whether the portion of the drainage system will be under public or private control or ownership.
All storm water management measures shall be designed in accordance with the design criteria contained in the Storm Water Management Design Guide using procedures contained in this manual or procedures approved by the City.
[Ord. No. 1677 §13, 9-22-1999]
Storm water management plans shall include at a minimum the following:
A vicinity map indicating a north arrow, scale, boundary lines of the site and other information necessary to locate the development site.
The existing and proposed topography of the development site.
Physical improvements on the site, including present development and proposed development.
Location, dimensions, elevations and characteristics of all storm water management facilities.
All areas within the site which will be included in the land disturbing activities shall be identified and the total disturbed area calculated.
The location of temporary and permanent vegetative and structural storm water management control measures.
An anticipated starting and completion date of the various stages of land disturbing activities and the expected date the final stabilization will be completed.
A determination that no occupied first (1st) floor elevation of any structure is below the one hundred (100) year plus one (1) foot flood elevation.
At the direction of the Community Development Director, for all portions of the drainage system which are expected to carry between fifty (50) and one hundred fifty (150) cfs for the one hundred (100) year storm, the one hundred (100) year plus one (1) foot flood elevation analysis, the Community Development Department will determine if one (1) of the following conditions may exist.
For all portions of the drainage system which are expected to carry one hundred fifty (150) cfs or more for the one hundred (100) year storm, the one hundred (100) year plus one (1) foot flood elevation analysis shall be done and flood limits shall be shown on the storm water management plans.
Storm water management plans shall include designation of all easements needed for inspection and maintenance of the drainage system and storm water management facilities. At a minimum, easements shall have the following characteristics:
Provide adequate access to all portions of the drainage system and structures.
Provide sufficient land area for maintenance equipment and personnel to adequately and efficiently maintain the system with a minimum of ten (10) feet along both sides of all drainage ways, streams, channels, etc., and around the perimeter of all detention and retention facilities or sufficient land use area for equipment access for maintenance of all storm water management facilities. The distance shall be measured from the top of the bank or toe of the dam, whichever is applicable.
Restriction on easements shall include prohibiting all fences and structures which would interfere with access to the easement areas and/or the maintenance function of the drainage system.
To improve the aesthetic aspects of the drainage system, a landscape plan for all portions of the drainage system shall be part of the storm water management plan. This landscape plan shall address the following:
Tree saving and planting plan.
Types of vegetation that will be used for stream bank stabilization, erosion control, sediment control, aesthetics and water quality improvement.
Any special requirements related to the landscaping of the drainage system and efforts necessary to preserve the natural aspects of the drainage system.
To improve the water quality aspects of the drainage system, the storm water management plan shall include best management practices to control the water quality of the runoff during the land disturbing activities and during the life of the development. This requirement is in addition to the requirements of the Missouri Department of Natural Resources Storm Water Pollution Prevention Permit.
The storm water management plans shall include all engineering calculations needed to design the system and associated structures including pre- and post-development velocities, peak rates of discharge and inflow and outflow hydrographys of storm water runoff at all existing and proposed points of discharge from the site.
Description of site conditions around points of all surface water discharge including vegetation and method of flow conveyance from the land disturbing activity.
Construction and design details for structural controls.
The expected timing of flood peaks through the downstream drainage system shall be assessed when planning the use of detention facilities.
In determining downstream effects from storm water management structures and the development, hydrologic-hydraulic engineering studies shall extend downstream to a point where the proposed development represents less than ten percent (10%) of the total watershed.
All storm water management facilities and all major potions of the conveyance system through the proposed development (i.e., channels, culverts) shall be analyzed using the design and one hundred (100) year storms for design conditions and operating conditions which can reasonably be expected during the life of the facility. The results of the analysis shall be included in the hydrologic-hydraulic study.
If the storm water management plan and/or design report indicates that there may be a drainage or flooding problem at the exit to the proposed development or at any location between the exit point and the ten percent (10%) downstream point, the Director of Community Development may require:
All storm water management plans submitted for approval shall contain certification by the person responsible for the land disturbing activity that the land disturbing activity will be accomplished pursuant to the approved plan and that responsible personnel will be assigned to the project. (See Exhibit C which is on file in the office of the Community Development Director.)
All storm water management plans shall contain certification, by the person responsible for the land disturbing activity, of the right of the City to conduct on-site inspections. (See Exhibit D which is on file in the office of the Community Development Director.)
No storm water management plan shall be considered approved without the inclusion of an approval signature and date on the plans by the Director of Community Development or his/her designee. The approval on the plan is solely an acknowledgement of satisfactory compliance with the requirements of these regulations. The approval does not constitute a representation or warranty to the applicant or any other person concerning the safety, appropriateness or effectiveness of any provision or omission from the storm water management plan.
Approved storm water management plans remain valid for five (5) years from the date of approval. Extensions or renewals of the plan approvals may be granted by the City Administrator upon written request by the person responsible for land disturbing activity.
[Ord. No. 1677 §14, 9-22-1999]
The hydrologic criteria to be used for the storm water concept and storm water management plans shall be as follows:
Twenty-five (25) year design storm for all cross-drain culverts and drainage designs.
Ten (10) year design storm for all interior culverts and drainage designs.
Two (2) and ten (10) year design storms for all detention and retention basins using procedures contained in the Storm Water Management Design Guide or approved by the Community Development Director.
All drainage designs and systems shall be checked using the one hundred (100) year storm for analysis of local flooding and possible flood hazards to adjacent structures and/or property. This check shall include completion of flow calculations for the one hundred (100) year extent for all drainage systems. The plan shall include a narrative description of how the one hundred (100) year flows are to be conveyed. If not included, then the one hundred (100) year overflow amount, depth velocity and flow width must be calculated and shown on the plans.
All hydrologic analysis will be based on land use conditions specified in Section 412.100(2).
For the design of storage facilities, a secondary outlet device or emergency spillway shall be provided to discharge the excess runoff in such a way that no danger of loss of life or facility failure is created. The size of the outlet device or emergency spillway shall be designed to pass the one hundred (100) year storm as a minimum requirement.
[Ord. No. 1677 §15, 9-22-1999]
Following are the criteria related to using storm water management facilities for water quality purposes:
Ponds, lakes and reservoirs.
When the land disturbing activity consists of the construction of a pond, lake or reservoir which is singly built and not part of a permitted land disturbing activity, the following procedures will apply:
A storm water management plan will not be required if the pond, lake or reservoir is permitted under the State Dams and Reservoirs Safety Act or has received a Certificate of Exemption from the State Dams and Reservoirs Safety Act. Best management practices should be used to minimize the impact of erosion and sediment.
A storm water management plan will be required for the construction of all ponds, lakes or reservoir not meeting the conditions in Subparagraph (1) above that otherwise meet the size requirement for storm water management plan approval.
When ponds are used for water quality protection, the ponds shall be designed as both quantity and quality control structures. Sediment storage volume shall be calculated considering the clean out and maintenance schedules specified by the designer during the land disturbing activity. Sediment storage volumes may be predicted by the Universal Soil Loss Equation or other methods acceptable to the Community Development Director.
Storm water runoff and drainage to a single outlet from land disturbing activities which disturb ten (10) acres or more shall be controlled during the land disturbing activity by a sediment basin where sufficient space and other factors allow these controls to be used until inspection. The sediment basin shall be designed and constructed to accommodate the anticipated sediment loading from the land disturbing activity and meet a removal efficiency of eighty percent (80%) suspended solids or 0.5 ML/L peak set table solids concentration, whichever is less. The outfall device or system design shall take into account the total drainage area flowing through the disturbed area draining to the basin.
Other practices may be acceptable to the City if they achieve an equivalent removal efficiency of eighty percent (80%) for suspended solids or 0.5 ML/L peak set table solids concentration, whichever is less. The efficiency shall be calculated for disturbed conditions for the ten (10) year twenty-four (24) hour design storm event.
Permanent water quality ponds having a permanent pool shall be designed to store and release the first (1st) one-half (½) inch of runoff from the site over a twenty-four (24) hour period. The storage volume shall be designed to accommodate at least one-half (½) inch of runoff from the entire site.
Permanent water quality ponds, not having a permanent pool, shall be designed to release the first (1st) inch of runoff from the site over a twenty-four (24) hour period.
The use of measures other than ponds to achieve water quality improvement are recommended on sites containing less than ten (10) disturbed acres.
Permanent infiltration practices, when used, shall be designed to accept, at a minimum, the first (1st) inch of runoff from all impervious areas.
Area drainage to infiltration practices must be established and vegetative filters established prior to runoff entering the system. Infiltration practices shall not be used if a suspended solids filter system does not accompany the practice. If vegetation is the intended filter, there shall be at least a twenty (20) feet width of vegetative filter prior to storm water runoff entering the infiltration practice.
The bottom of the infiltration practice shall be at least two (2) feet above the seasonal high water table, whether perched or regional, determined by direct piezometer measurements which can be demonstrated to be representative of the maximum height of the water table on an annual basis during years of normal precipitation or by the depth in the soil at which mottling first occurs.
The infiltration practice shall be designed to completely drain off water within seventy-two (72) hours.
Soils must have adequate permeability to allow water to infiltrate. Infiltration practices are limited to soils having an infiltration rate of at least 0.30 inches per hour. Initial consideration will be based on a review of the appropriate soil survey, and the survey may serve as a basis for rejection. On-site soil borings and textural classifications must be accomplished to verify the actual site and seals on high water table conditions when infiltration is to be utilized.
Infiltration practice greater than three (3) feet deep shall be located at least ten (10) feet from basement walls.
Infiltration practices designed to handle runoff from impervious parking areas shall be a minimum of one hundred fifty (150) feet from any public or private water supply wall.
The design of infiltration practice shall provide an overflow system with measures to provide a non-erosive velocity of flow along its length and at the outfall.
The slope of the bottom of the infiltration practice shall not exceed five percent (5%). Also, the practice shall not be installed in fill material, as piping along the fill/natural ground interface may cause slope failure.
An infiltration practice shall not be installed on or atop a slope whose natural angle of incline exceeds twenty percent (20%).
Clean outs will be provided, at a minimum, every one hundred (100) feet along the infiltration practice to allow for access and maintenance.
[Ord. No. 1677 §16, 9-22-1999]
Storm water concept and storm water management plans and design reports that are incidental to the overall or ongoing site design shall be prepared, certified and stamped/sealed by a qualified registered Missouri professional engineer, land surveyor or landscape architect using acceptable engineering standards and practices. All other storm water concept and storm water management plans and design reports shall be prepared, certified and stamped/sealed by a qualified registered Missouri professional engineer using acceptable engineering standards and practices.
The engineer, surveyor or landscape architect shall perform services only in areas of his/her competence and shall undertake to perform engineering or land surveying assignments only when qualified by education and/or experience in the specific technical field. In addition, the engineer, surveyor or landscape architect must verify that the plans have been designed in accordance with this Chapter and the standards and criteria stated or referred to in this Chapter.
[Ord. No. 1677 §17, 9-22-1999]
All storm water management facilities shall be privately owned and maintained unless the City Council accepts the facility for municipal ownership and maintenance. The owner of all private facilities shall grant to the City a perpetual non-exclusive easement which allows for public inspection and emergency repair.
All storm water management measures relying on designed vegetated areas or special site features shall be privately owned and maintained as defined on the storm water management plan.
Most regional storm water management facilities will be publicly owned and/or maintained.
[Ord. No. 1677 §18, 9-22-1999]
When the City determines that additional storage capacity beyond that required by the applicant for on-site storm water management is necessary in order to enhance or provide for the public health, safety and general welfare to correct unacceptable or undesirable existing conditions or to provide protection in a more desirable fashion for future development, the City may:
Require that the applicant grant any necessary easement over, through or under the applicant's property to provide access to or drainage for such a facility;
Require that the applicant attempt to obtain from the owners of property over, through or under where the storm water management facility is to be located any easement necessary for the construction and maintenance of same. Failing to obtain such easements, the City may, at its option, assist in such matters by purchase, condemnation, dedication or otherwise and subject to Subsection (3) below, with any cost incurred thereby to be paid by the City; and/or
Participate financially in the construction of such facility to the extent that such facility exceeds the required on-site storm water management as determined by the City.
To implement this provision, both the City and developer must be in agreement with the proposed facility that includes the additional storage capacity and jointly develop a cost-sharing plan which is agreeable to all parties.
[Ord. No. 1677 §19, 9-22-1999]
Any storm water discharge control facility which services a single lot or commercial and industrial development shall be privately owned and maintained; provided however, the owner thereof shall grant to the City a perpetual, non-exclusive easement which allows for public inspection and emergency repair in accordance with the maintenance agreement set forth in Section 412.190.
All regional storm water discharge control facilities identified on municipal storm water discharge control master plans shall be publicly owned and/or maintained only if accepted for maintenance by the City Council.
All other storm water discharge control facilities shall be publicly owned and/or maintained only if accepted for maintenance by the City Council.
Private maintenance requirements shall be a part of the plat of the subdivision.
[Ord. No. 1677 §20, 9-22-1999]
A proposed inspection and maintenance agreement shall be submitted to the Community Development Director for review and for approval of the City Council for all private on-site storm water discharge control facilities prior to the approval of the storm water management plan. (See Exhibit I which is on file in the office of the Community Development Director.) Such agreement shall be in form and content acceptable to the City Council and shall be the responsibility of the private owner. Such agreement shall provide for access to the facility by virtue of a non-exclusive perpetual easement in favor of the City at reasonable times for regular inspection by the City. The agreement will identify who will have the maintenance responsibility. Possible arrangements for this maintenance responsibility might include the following:
All maintenance agreements shall contain without limitation the following provisions:
A description of the property on which the storm water management facility is located and all easements from the site to the facility;
Site and configuration of the facility;
A statement that properties which will be served by the facility are granted right to construction, use, reconstruction, repair, maintenance and access to the facility;
A statement that each lot served by the facility is responsible for repairs and maintenance of the facility and any unpaid ad valorem taxes, public assessments for improvements and unsafe building and public nuisance abatement liens charged against the facility, including all interest charges together with attorney fees and cost of expenses of collection. If an association is delegated these responsibilities, then membership into the association shall be mandatory for each parcel served by the facility and any successive buyer. The association shall have the power to levy assessments for these obligations and that all unpaid assessments levied by the association shall become a lien in the individual parcel; and
A statement that no amendments to the agreement will become effective unless approved by the City Council.
The agreement shall provide that preventive maintenance inspections of storm water management facilities may be made by the City, at its option, without limiting the generality of the foregoing. The City's inspection schedule may include an inspection during the first (1st) year of operation and once every year thereafter and after major storm events (i.e., five (5) or ten (10) year floods).
Inspection reports shall be maintained by the Community Development Department.
The agreement shall provide that if, after an inspection, the condition of a facility presents an immediate danger to the public health, safety or general welfare because of unsafe conditions or improper maintenance, the City shall have the right, but not the duty, to take such action as may be necessary to protect the public and make the facility safe. Any cost incurred by the City shall be paid by the owner.
The agreement shall be recorded by the owner in the Register of Deeds prior to the final inspection and approval.
The agreement shall provide that the Community Development Director shall notify the owner(s) of the facility of any violation, deficiency or failure to comply with this Chapter. The agreement shall also provide that upon a failure to correct violations requiring maintenance work, within thirty (30) days after notice thereof, the City may provide for all necessary work to place the facility in proper working condition. The owner(s) of the facility shall be assessed the costs of the work performed by the City pursuant to Subsection (F) above. There shall be a lien on all property of the owner(s) whose property utilizes or will utilize such facility in achieving discharge control, which lien, when filed in the Register of Deeds, shall have the same status and priority as liens for ad valorem taxes. Should such a lien be filed, portions of the affected property may be released by the City Administrator following the payments by the owner of such owner's pro rata share of the lien amount based upon the acreage to be released with such release amount to be determined by the City Administrator at his/her reasonable discretion.
The City Administrator, at his/her discretion, may accept the certification of a registered engineer in lieu of any inspection required by this Chapter.
[Ord. No. 1677 §21, 9-22-1999]
Prior to the approval of the storm water management plan, the applicant shall submit to the Community Development Department a proposed staged construction and inspection control schedule. This plan shall indicate a phase line for approval. Otherwise, the construction and inspection control schedule will be for the entire drainage system.
Bi-stage work, related to the construction of storm water management facilities, shall proceed until the next proceeding stage at work, according to the sequence specified in the approved staged construction and inspection control schedule, is inspected and approved by the Community Development Director or his/her designee.
Any portion of the work which does not comply with the storm water management plan shall be promptly corrected by the permittee.
The permittee shall notify the Community Development Department before commencing work to implement the storm water management plan.
The permittee shall provide an "as-built" plan certified by a registered professional (as outlined in Section 412.120) to be submitted upon completion of the storm water management facilities included in the storm water management plan. The registered professional shall certify that:
A final inspection shall be conducted by the Community Development Director or his/her designee upon completion of the work included in the approved storm water management plan to determine if the completed work is constructed in accordance with the plan.
The Community Development Department shall maintain a file of inspection reports and provide copies of all inspections reports to the permittee that include the following (See Exhibit J which is on file in the office of the Community Development Director):
[Ord. No. 1677 §22, 9-22-1999]
The Board of Zoning Adjustments may grant a variance from the requirements of this Chapter if there are exceptional circumstances applicable to the site such that strict adherence to the provisions of the ordinance will result in unnecessary hardship and not fulfill the intent of the ordinance.
A written request for a variance submitted to the Community Development Director shall be required and shall state the specific variance and the reasons, with supporting data, for their granting. The request shall include descriptions, calculations and any other information that is necessary to evaluate the proposed variance.
Any substantial variance from the storm water management plan or concept plan shall be referred to all agencies which reviewed the original plan.
The Community Development Department will conduct a review of the request for variance and submit findings to the City Administrator for recommendation to the City Council.
[Ord. No. 1677 §23, 9-22-1999]
Review Of Community Development Director Decision. Any individual company or corporation aggrieved or prejudiced by decision of the Community Development Director or his/her designee concerning the storm water management ordinance shall be entitled to request a review of said decision. Said review shall be conducted by the City Administrator pursuant to the following procedure:
The City Clerk shall maintain a form for requesting review before the City Administrator.
Said request shall be filed within ten (10) days of the applicant's receipt of notice of the decision which is being reviewed. Said request for review shall state the specific manner in which the decision of the Community Development Director is alleged to be in error.
Upon receipt of the request for review, the City Administrator shall immediately notify the Community Development Director and the Director shall have five (5) days in which to submit a written response of said request for review.
Within ten (10) days after receiving the response of the Community Development Director or within fifteen (15) days of filing of the notice of appeal, if no such response is submitted, the City Administrator shall render a decision affirming, reversing or modifying the decision of the Community Development Director. In the alternative, if deemed appropriate by the City Administrator, the City Administrator may decline to render a decision and direct the matter to be submitted to the City Council and a review conducted pursuant to the following paragraphs.
Review Of City Administrator Decision. Any individual, company or corporation aggrieved or prejudiced by the decision of the City Administrator concerning the storm water management ordinance shall be entitled to request review of said decision. Said review shall be conducted by the City Council pursuant to the following:
City Clerk shall maintain a form requesting a review before the City Council.
Said request shall be filed within fifteen (15) days of the applicant's receipt of notice of the decision of the City Administrator which is being reviewed.
The notice of appeal shall state the specific reason why the decision of the City Administrator is alleged to be in error.
Upon receipt of the appeal, the City Clerk shall immediately notify the City Administrator of the receipt of the appeal and the City Administrator shall have a period of five (5) days in which to prepare a written response to said appeal. A copy of said response shall be provided to the applicant.
The hearing shall be held before the City Council not less than twenty-one (21) days after receipt by the City Clerk of the request for review, unless extended by the City Council upon mutual agreement of the parties or for good cause shown.
At the hearing, the City Council shall have the right to examine the drawings, diagrams, books, records and papers pertinent to the issues before it. The City Council shall have the power to issue any necessary subpoenas over the signature of the City Clerk and to issue all necessary processes to subpoena witnesses to compel by subpoena duces tecum issued over the signature of the City Clerk, the production of books, records, papers and other evidence and to administer oaths and testimony.
The individual, company or corporation aggrieved shall have the full right to be represented by counsel and may produce witnesses and cross-examine all witnesses who appear against him/her at any hearing held hereunder. Witnesses may appear voluntarily at such hearing and testimony. Before any witness shall testify in any such hearing or proceeding, said witness shall be sworn to tell the truth by the Mayor.
All decisions, finding and orders of the City Council to the proceedings shall be notified of the decision by the City Council by certified mail to the address listed on the request for review.
Based on the evidence produced at the hearing, the City Council shall make an order as supported by the evidence, including the following:
Affirm the decision of the City Administrator and/or Community Development Director.
Reverse the decision of the City Administrator and/or Community Development Director.
Affirm or reverse the decision of the City Administrator and/or Community Development Director with such modifications to the appealed decision as Council deems appropriate and is supported by evidence.
Review Of City Council Decision. Following any decision or ruling by the City Council relating to the storm water management ordinance, any individual, company or corporation aggrieved or prejudiced by said decision or ruling may seek judicial review of the matter provided by law. The City Council may stay enforcement of its decision or ruling for a period of time, not to exceed thirty (30) days, pending the filing or final disposition of an application for judicial review.
[Ord. No. 1677 §24, 9-22-1999]
It shall be unlawful for any person to violate any provision of the storm water management ordinance. Upon conviction thereof, such person shall be judged guilty of a misdemeanor and punished by a fine not exceeding five hundred dollars ($500.00) or be incarcerated for a period not to exceed three (3) months, or by both such fine and incarceration. Each day's violation of, or failure, refusal or neglect to comply with any provision of the storm water management ordinance shall constitute a separate and district offense.
[Ord. No. 1677 §25, 9-22-1999]
At the decision of City Council and in addition to or an alternative remedy from the provision previously noted herein, the City Council may seek to have the practices, violations or failure to comply with the provision of the storm water management ordinance abated by an action for injunction or other civil proceedings to be maintained in the appropriate Circuit Court for the State of Missouri or other appropriate forum.
[Ord. No. 1677 §26, 9-22-1999]
Any applicant or owner of a parcel of land within the jurisdiction of the City who has constructed the required storm water management facility or who is in the process of meeting the storm water management requirements of the law at the time of the effective date of this Chapter, September 22, 1999, may elect to apply to the City Council for reconsideration under the provisions of this Chapter.
[Ord. No. 1677 §27, 9-22-1999]
Whenever the provisions of this Chapter impose more restrictive standards than are required in or under any other ordinance, the regulations herein contained shall prevail. Whenever the provisions of any other ordinance require more restrictive standards than are required herein, the requirement of such shall prevail.
[Ord. No. 1677 §28, 9-22-1999]
Neither the approval of a plan under the provisions of this Chapter nor the compliance with the provisions of this Chapter shall relieve any person from the responsibility for damage to any person or property otherwise imposed by law nor shall it impose any liability upon the City for damage to any person or property.