40-98 Ordinance AMENDEDRECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98 ~Qrn eh~e~) pissed
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AN ORDINANCE TO ESTABLISH CHAPTER 53, AND TO AMEND
SECTIONS 152.002 and 152.050 OF THE DUBLIN CODE OF ORDINANCES
WITH RESPECT TO STORMWATER MANAGEMENT
AND DECLARING AN EMERGENCY
WHEREAS, the City of Dublin, Ohio has experienced problems from runoff
during storm events; and
WHEREAS, the City is desirous of amending the aforesaid regulations and
readopting said regulations upon the advice of the City Engineer; and
WHEREAS, The City has determined that the drainage and development of land
usually has significant impact upon the health, safety, and welfare of the residents of
Dublin, Ohio; and
WHEREAS, improperly managed stormwater runoff can increase the incidence
of flooding and potentially endangering human life and property; and
WHEREAS, construction requiring the alteration of natural topography and
removal of vegetation tends to increase erosion; and
WHEREAS, improperly channeling water increases the velocity of runoff,
thereby increasing erosion and sedimentation; and
WHEREAS, siltation of water bodies resulting from increased erosion decreases
their capacity to hold and transport water; and
WHEREAS, stormwater runoff can carry pollutants into receiving water bodies,
thus degrading water quality; and
WHEREAS, impervious surfaces increase the volume and rate of stormwater
runoff and potentially allow less water to percolate into the soil, thereby decreasing
groundwater recharge; and
WHEREAS, adverse economic impacts could result from these undesirable
impacts on waters; and
WHEREAS, many problems can be avoided if land is developed in accordance
with sound stormwater runoff management practices; and
WHEREAS, the Dublin City Council Community Development Committee has
reviewed the proposed amendments and made a recommendation of approval of this
Ordinance to the City Council.
NOW, THEREFORE, be it ordained by the Council of the City of Dublin, State
of Ohio, ~ of the elected members concurring:
RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____ 40-98______.___ Passed_______ _____________
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SECTIONI. To Establish Chapter 53 of the Dublin Code of Ordinances as follows:
53.010 PURPOSE.
An Ordinance regulating stormwater from areas of new development and
redevelopment for the purpose of protecting the public health, safety, and welfare;
defining appropriate stormwater management objectives for the quantity and quality of
stormwater runoff in the City; providing for waivers; providing requirements for the
protection of water resources; imposing application fees and procedures; requiring
adherence to the plans approved by the City Engineer; providing for maintenance; and
providing for enforcement and penalties for violation.
In order to protect, maintain, and enhance both the immediate and the long-term
health, safety, and general welfare of the citizens of Dublin, it is the intent of the City to
enact this Ordinance so as to accomplish the following objectives:
(A) To prevent loss of life and loss of property due to flooding;
(B) To protect, restore, and maintain the chemical, physical, and biological
quality of ground and surface waters;
(C) To encourage productive and enjoyable harmony between humanity and
nature;
(D) To prevent individuals, business entities, and governmental entities from
causing harm to the community by activities which adversely affect water
resources;
(E) To encourage the protection of natural systems and the use of those
natural systems in ways which do not impair their beneficial functioning.
(F) To minimize the transport of sediments and pollutants to surface water
and groundwater;
(G) To protect and maintain the habitat of fish and wildlife;
(H) To help perpetuate natural groundwater recharge;
(I) To encourage the use of natural drainage systems; and
(J) To ensure the attainment of these objectives by requiring the approval and
implementation of stormwater management plans for all activities which may
have an adverse impact upon groundwater and surface water.
53.020 SHORT TITLE.
This Ordinance shall be known and cited as "The City of Dublin, Ohio
stormwater Management Ordinance", hereinafter referred to as the "stormwater
Regulations"
53.030 JURISDICTION.
The stormwater Regulations shall apply in all areas within the development
jurisdiction of the City of Dublin, Ohio.
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Davton Le¢el Blank Co. Form No. 30043
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53.040 DEFINITIONS.
For the purpose of the Stormwater Regulations, the following terms, phrases, and
definitions shall apply. Words used in the singular shall include the plural, and the
plural, the singular. Words used in the present tense shall include the future tense. The
word "shall" is mandatory and not discretionary. The word "may" is permissive. Words
not defined herein shall be construed to have the meaning given by common and ordinary
use as defined by the latest edition of Webster's Dictionary.
Accelerated Water Erosion shall mean the wearing away of the land surface
by water, occurring at a much more rapid rate than geologic or normal erosion,
primarily as a result of the influence of the activities of humans.
Agricultural Lands shall mean those lands in any agricultural use, including
forestry.
Applicant shall mean any person or duly designated representative applying
for a permit or other type of City of Dublin, federal, or state regulatory approval to
proceed with a project.
Approving Agency shall mean the City Engineer of the City of Dublin, Ohio.
Aquifer shall mean an underground formation, group of formations, or part of
a formation that is permeable enough to transmit, store, or yield usable quantities of
water.
As-Built Plans shall mean the final plans amended to include all locations,
dimensions, elevations, capacities, capabilities, as actually constructed and installed.
BMP, or Best Management Practices shall mean programs, technology,
processes, siting criteria, operating methods, measures, or devices which control,
prevent, remove, or reduce pollution.
Channel shall mean a natural stream that conveys water, a ditch, or channel
excavated for the flow of water.
Clearing shall mean the removal of trees, brush, and other ground cover from
apart of the land, but shall not include mowing.
Compensating Storage shall mean equivalent floodplain storage provided to
counterbalance floodplain filling.
Concentrated Storm Runoff shall mean surface runoff which converges and
flows primarily through water conveyance features such as swales, gullies,
waterways, channels or storm sewers and which exceeds the maximum specified flow
rates of filters or perimeter controls intended to control sheet flow.
Conservation shall mean the wise use and management of natural resources.
Conservation Plan shall mean a formal document which outlines a system of
management practices to control soil erosion and to improve water quality for a
specific parcel of property, and which has been prepared by the United States
Department of Agriculture Soil Conservation Service (SCS) in conjunction with the
Union, Delaware, or Franklin County Soil and Water Conservation Districts; by an
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RECORD OF ORDINANCES
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independent consultant to standards, specifications, and guidelines developed by the
SCS; or by a private consultant based on SCS guidelines using guidelines for
Conservation Plans using accepted engineering principles, and which provides an
equivalent level of treatment.
Construction shall mean the building, assembling, expansion, modification or
alteration of the existing contours of the site, the erection of buildings or other
structures, or any part thereof, or land clearing.
Cut and Fill Slopes shall mean a portion of land surface or area from which
soil material is excavated and/or filled forming a slope or embankment.
Detention or To Detain shall mean the prevention of, or to prevent, the
discharge, directly or indirectly, of a given volume of stormwater runoff into surface
waters by temporary onsite storage.
Development or Development Activity shall mean the alteration,
construction, installation, demolition or removal of a structure, impervious surface or
drainage facility; or clearing, scraping, grubbing, killing or otherwise removing the
vegetation from a site; or adding, removing, exposing, excavating, leveling, grading,
digging, burrowing, dumping, piling, dredging or otherwise significantly disturbing
the soil, mud, sand or rock of a site.
Directly Connected Impervious Areas are those impervious areas which are
connected to the City's drainage system by a ditch, storm sewer, paved channel, or
other man-made conveyance.
Discharge shall mean the outflow of water from a project, site, aquifer,
drainage basin or facility.
Ditch shall mean an artificial waterway for irrigation or stormwater
conveyance.
Drainage Facility shall mean any component of the stormwater management
system.
Drainage System shall mean all facilities used for the movement of
stormwater through and from a drainage area, including, but not limited to, any and
all of the following conduits and appurtenant features: channels, ditches, flumes,
culverts, streets, as well as all watercourses, waterbodies and wetlands.
Easement shall mean a grant by a property owner for the use of a specified
portion of land for a specified purpose.
Erosion shall mean the wearing or washing away of soil by the action of
water.
FEMA shall mean Federal Emergency Management Agency.
Forebays shall mean areas with hardened bottoms located at detention basin
inlets that are designed to trap coarse sediment particles by separating approximately
10 percent of the basin volume from the remainder of the basin with a lateral sill,
rock-filled gabions, a retaining wall, or horizontal rock filters.
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Groundwater shall mean water below the surface of the ground whether or
not flowing through known of defined channels.
Hydrograph shall mean a graph of discharge versus time for a selected point
in the drainage system.
Dlicit Connections shall mean any natural or man-made conveyance or
drainage system, pipeline, conduit, inlet, or outlet (including natural surface flow
patterns, depressions or channels traversing one or more properties) through which
the discharge of any pollutant to the stormwater drainage system occurs or may occur,
unless the connection is authorized under a discharge permit issued by the Ohio EPA.
Impervious Surface shall mean a surface which has been compacted or
covered with a layer of material so that it is resistant to infiltration by water. It
includes semi-pervious surfaces such as compacted clay, as well as most
conventionally surfaced streets, roofs, sidewalks, parking lots, and other similar
surfaces.
Intensity shall mean the depth of accumulated rainfall per unit of time.
Maintenance shall mean the action taken to restore or preserve the as-built
functional design of any facility or system.
ODNR shall mean Ohio Department of Natural Resources.
ODOT shall mean Ohio Department of Transportation.
OEPA shall mean Ohio Environmental Protection Agency.
Open Channel shall mean a ditch, channel, or swale used to safely convey
stormwater runoff.
Outdoor Activity Areas shall mean areas where pollutants are or may
become more concentrated than typical urban runoff as characterized by the USEPA
National Urban Runoff Program (NURP), as listed below or otherwise defined by the
City Engineer:
(1) Industrial material, waste handling, and storage areas, including but
not limited to loading docks, fuel and other liquid storage/dispensing
facilities, material bins, containers, stockpiles, and other storage
containers, waste dumpsters, bins, cans, tanks, stockpiles, and other
waste containers.
(2) Processing, manufacturing, fabrication, cleaning, or other permanent
outdoor equipment or work areas.
(3) Areas where vehicles and equipment are repaired, maintained, stored,
disassembled, or disposed.
Owner shall mean the person in whom is vested the fee, ownership,
dominion, or title of property (i.e., the proprietor). This term may also include a
tenant, if chargeable under his lease for the maintenance of the property, and any
agent of the owner or tenant including a developer.
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Parcel or Parcel of Land shall mean a contiguous quantity of land in
possession of owned by, or recorded as property of the same claimant person as of the
effective date of the Stormwater Regulations.
Peak Rate of Flow shall mean the maximum rate of discharge resulting from
a given storm event.
Permittee shall mean any person who has been granted a permit to proceed
with a project.
Person shall mean any individual, firm, corporation, governmental agency,
business trust, estate, trust, partnership, association, two or more persons having a
joint or common business interest, or any other legal entity.
Positive Outlet shall mean a gravity discharge from a basin via overland flow,
artificial waterway, natural waterway, or pipe.
Post-Development shall refer to the average conditions as of the completion
of the development for which a permit has been applied.
Pre-Development shall mean the hydrologic and hydraulic condition of the
project site immediately before development or construction begins.
Professional Engineer shall mean a Professional Engineer licensed by the
State of Ohio, skilled in the practice of civil engineering and the engineer of record
for the project under consideration.
Prohibited Discharges shall mean any discharges which are not composed
entirely of stormwater unless authorized under a discharge permit issued by the
OEPA.
Rainfall Intensity shall mean the depth of accumulated rainfall per unit of
time.
Rate shall mean volume per unit of time.
Receiving Waters or Waterbodies shall mean any waterbodies,
watercourses, and wetlands into which surface waters flow.
Recharge shall mean the inflow of water into an aquifer.
Retention or To Retain shall mean the prevention of, or to prevent, the
discharge, directly or indirectly, of a given volume of stormwater runoff into surface
waters by complete onsite storage.
SCS shall mean the United States Department of Agriculture Soil
Conservation Service.
Sediment shall mean solid material, whether mineral or organic, that is in
suspension, is being transported, or has been moved from its site of origin by water.
Sedimentation Control Device shall mean any structure or area which is
designed to hold runoff water until suspended sediments have settled.
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Site shall mean any tract, lot, or parcel of land or combination of tracts, lots,
or parcels of land which is in one ownership, or contiguous and in diverse ownership
where development is to be performed as part of a unit, subdivision, or project.
Storm Event shall mean the storm of a specific duration, intensity, and
frequency.
Stormwater or Runoff shall refer to the flow of water which results from, and
which occurs during and immediately following a rainfall event.
Stormwater Design Standards shall mean the design standards presented in
the Stormwater Regulations, and other standards adopted by the City.
Stormwater Management Plan shall refer to the approved detailed analysis,
design, and drawings of the Stormwater management system required for all
construction.
Stormwater Management System or Facilities shall refer to designed and/or
constructed features which collect, convey, channel, store, inhibit, or divert the
movement of Stormwater.
Stormwater Master Plan shall mean the technical and policy manuals and
any subsequent updates or amendments thereto used by the City Engineer to
administer the Stormwater Regulations.
Stormwater Quality shall mean any liquid, solid, or semi-solid substance, or
combination thereof, that enters stormwater runoff in concentrations or quantities
large enough to contribute to the degradation of the beneficial uses of the body of
water receiving the discharge.
Structure shall mean anything constructed or installed with a fixed location
on the ground, or attached to something having a fixed location on the ground.
Subgrade shall mean the top elevation of graded and compacted earth
underlying roadway pavement.
Swale shall mean an artificial or natural waterway which may contain
contiguous areas of standing or flowing water only following a rainfall event, or is
planted with or has stabilized vegetation suitable for soil stabilization, stormwater
treatment, and nutrient uptake, or is designed to take into account the soil erodibility,
soil percolation, slope, slope length, and contributing area so as to prevent erosion
and reduce the pollutant concentration of any discharge.
SWMM shall mean the United States Environmental Protection Agency
Stormwater Management Model, which serves as the technical basis for the City of
Dublin Stormwater Master Plan.
Tailwater shall mean the water into which a spillway or outfall discharges.
USEPA shall mean United States Environmental Protection Agency
Waterbody shall mean any natural or artificial pond, lake, reservoir, or other
area which ordinarily or intermittently contains water and which has a discernible
shoreline.
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Watercourse shall mean any natural or artificial stream, creek, channel, ditch,
canal, waterway, gully, ravine, or wash in which water flows either continuously or
intermittently, and which has a definite channel, bed, or banks.
Wet Detention shall mean a detention basin that contains a permanent pool of
water that will retain runoff for a minimum period of 14 days for an average rainfall
summer, and which has a littoral zone over a substantial portion of the pond surface
area.
Wetlands shall mean those areas that are inundated or saturated by surface or
groundwater with a frequency and duration sufficient to support, and that under
normal circumstances do support, a prevalence of vegetation typically adapted for life
in saturated soil conditions. Wetlands generally include swamps, marshes, bogs, and
similar areas.
Works shall mean all artificial structures, including, but not limited to, canals,
ditches, swales, conduits, channels, culverts, pipes, and other construction that
connects to, draws water from, drains water into, or is placed in or across the waters
in the state.
53.050 AUTHORITY.
The City Engineer is hereby authorized to administer the Stormwater
Regulations. The City Engineer shall maintain and update the Stormwater Master Plan
and recommend to City Council for adoption modifications in the Stormwater Master
Plan, detailed design studies or procedures to reflect new construction and/or engineering
design technology.
53.060 REQUIRED APPROVALS.
(A) The requirements of the Stormwater Regulations shall be implemented,
and shall be satisfied completely, prior to final project approval by the City Engineer.
No person shall conduct any development activity, or subdivide or make any change in
the use of land, or construct any stormwater management system or structure, or change
the size of an existing structure or system, except as may be exempted in Section 53.070
of the Stormwater Regulations.
(B) Any construction plans, specifications, or other documents approved by
the City Engineer shall be constructed in accordance with all applicable state or federal
permit requirements of the Ohio Environmental Protection Agency (OEPA), Ohio
Department of Natural Resources (ODNR) and/or U. S. Army Corps of Engineers. No
construction activity shall commence prior to obtaining applicable permits from these
agencies.
53.070 EXEMPTIONS.
With the approval of City Council, the following activities may be exempted
from on-site stormwater runoff control. An exemption shall apply only to the
requirement for on-site stormwater detention or retention facilities. All other design
elements such as the storm sewer system, road culverts, erosion and sedimentation
control, and runoff quality shall not be exempted.
(A) Emergency exemption. Emergency maintenance work performed for the
protection of public health and welfare.
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(B) Maintenance Exemption. Any maintenance to an existing system made
in accordance with plans and specifications approved by the City Engineer.
(C) Development-related Exemptions. The Applicant shall provide to the
City Engineer in writing a request for exemption which shall include a scaled site map,
property tax number, and street address if applicable.
(1) Single-Family or Duplex Exemption. Single-family or duplex
residential construction on a single lot that is not part of a larger common
plan of development.
(2) Scioto River Corridor Exemption. Parcels that that are located
between State Route 745 (Dublin-Granville Road) and State Route 257
(Riverside Drive) which are directly tributary to the Scioto River.
53.080 GENERAL REQUIREMENTS.
(A) A stormwater management system shall be designed and installed for the
development that will contain features to provide for flood protection, erosion control,
and runoff pollution abatement. The stormwater management system design shall
conform to the Stormwater Design Standards contained in Section 53.090 of the
Stormwater Regulations, the Stormwater Master Plan and other standards specified by
the City Engineer. The intent of these design standards is to encourage environmentally
sound stormwater management practices; they should go beyond providing drainage
facilities. Developments that sacrifice recharge and upland controls in order to maximize
the number of lots will not be allowed. The City's stormwater management perspective
includes the management of both water quantity and water quality. Stormwater
management design shall blend into the natural environment and be aesthetically
integrated into site design.
(B) All development activity within a Special Flood Hazard Area designated
by the Federal Emergency Management Agency (FEMA) shall comply with Chapter 151
of the Dublin Code of Ordinances. All development shall be designed to maintain the
flood carrying capacity of the floodway such that the base flood elevations are not
increased, either upstream or downstream. Furthermore, no fill shall be allowed to be
placed in the 100-year floodplain without an equivalent volume of soil removed to
compensate for the loss of the flood storage. Compensating storage shall be determined
by the volume of material removed above the ordinary high water table and below the
100-year flood elevation established for that area. Compensating storage shall be
provided within the legal boundaries of the development.
(C) The stormwater management system shall not create an adverse impact
on stormwater quantity or quality in either upstream or downstream areas. Offsite areas
which discharge to or across a site proposed for development shall be accommodated in
the stormwater management plans for the development. No stormwater management
plan shall be approved until it is demonstrated that the runoff from the project shall not
overload or otherwise adversely impact any downstream areas.
(D) Wetlands shall not be used for stormwater management or stormwater
runoff quality treatment.
(E) All proposed stormwater management systems shall be designed to
prevent the pollution of groundwater resources by stormwater, promote safety, minimize
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health hazards, preserve natural features, and provide for recharge where appropriate.
Neither submission of a plan under the provision herein nor compliance with the
provisions of these Regulations shall relieve any person from responsibility for damage
to any person or property otherwise imposed by law.
(F) Where deemed necessary by the City Engineer, the Applicant shall
construct storm drains to handle on-site runoff; provide on-site drainage easements;
provide off-site drainage easements; and provide for the conveyance of off-site runoff
to an acceptable outlet in the same watershed. However, the on-site drainage easements
may not encroach on required perimeter landscaping.
53.090 5TORMWATER DESIGN STANDARDS.
(A) General.
The ODOT Drainage Design Manual and any subsequent revisions thereto shall
be used for the design of storm sewers, culverts, open channels, and permanent and
temporary erosion and sedimentation control. The latest edition of "The Water
Environment Federation Manual of Practice ", No. 23 and "American Society of Civil
Engineers Manul and Report on Engineering Practice ", No. 87 shall be used for the
design of stormwater runoff quality control features of site development. The City
Engineer shall recommend to City Council for adoption any modifications to the design
standards of these documents.
(B) Hydraulic Design Criteria.
(1) If USEPA Stormwater Management Model (SWMM)
methodology is used, the duration of the storm shall be 24 hours and the
rainfall time increment shall be six (6) minutes. If Rational Formula,
United States Department of Agriculture Soil Conservation Service
(SCS) TR-55 or TR-20, or HEC-1 methodology are used, rainfall
intensities are to be obtained from the "Rainfall Frequency Atlas of the
Midwest", 1992, and any subsequent updates thereto.
(2) The design frequency for major drainage systems may be
increased if deemed necessary by the City to protect upstream or
downstream properties or to comply with other regulations.
(3) Rainfall volumes shall be in accordance with data for Central
Ohio provided in the "Rainfall Frequency Atlas of the Midwest", 1992,
and any subsequent updates thereto.
(4) Rainfall distribution for Stormwater management systems is to be
in accordance with SCS Type II Rainfall Distribution.
(C) Detention/RetentionFadlities
A detention/retention facility shall be installed on all development
projects, unless the Applicant demonstrates that the project will not increase the
peak rate of runoff; volume, or frequency of the runoff hydrograph of the site
prior to development. Detention/retention facilities shall be designed in the
following manner:
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(1) Studied Areas. Parcels located within drainage sub-basins
established in the Stormwater Master Plan, or any subsequent update
thereto shall comply to the runoff release rate for each frequency storm
specified in the Stormwater Master Plan.
(a) Critical Storm Controls. Determine the total volume of
runofffrom a 1-year, 24-hour storm, occurring over each
of the site's drainage areas before and after development.
(b) Determine the percent of increase in runoff volume due to
development and using this percentage, select the critical
storm from Table 53-01.
(c) The peak rate of runoff from the critical storm occurring
over the developed site shall not exceed the peak rate of
runoff from a 1-year, 24-hour storm occuring over the
same area prior to development, as defined in the
Stormwater Master Plan. Storms of less frequent
occurrence (longer return period) than the critical storm,
shall have the peak rate of runoff not greater than for the
same storm under pre-development conditions.
TABLE 53-01
CRITICAL STORM DETERNIINATION
If the Percent of Increase in The Critical
Runoff Volume is Storm Runoff
Equal to or Rate Will Be
Greater than And less than Limited to:
-- 10 1 year
10 20 2 year
20 50 5 year
50 100 10 year
100 250 25 year
250 500 50 year
500 -- 100 year
(2) Unstudied Areas. Detention/retention facilities designed for
parcels located outside drainage sub-basins established with the
Stormwater Master Plan, or any subsequent update thereto shall comply
to the following minimum design criteria:
(a) Development of sites other than single-family and less
than or equal to 2.0 acres shall not release stormwater
runoff greater than 0.2 cubic feet per second per acre of
development. On-site detention storage shall be provided
according to Table 53-02.
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(b) Development sites greater than 2.0 acres shall provide
runoff controls as follows:
1. Critical Storm Controls. Determine the total
volume of runoff from a 1-year, 24-hour storm,
2. Determine the percent of increase in runoff
volume due to development and using this
percentage, select the critical storm from Table
53-01.
3 . Determine the peak rate of runoff for the 1-year,
2-year, 5-year, 10-year, 25-year, 50-year and 100-
year, 24-hour storms occurring over each of the
site's drainage areas before and after
development.
3. The peak rate of runoff from the critical storm
occurring over the developed site shall not exceed
the peak rate of runoff from a 1-year, 24-hour
storm occuring over the same area prior to
development. Storms of less frequent occurrence
(longer return period) than the critical storm, shall
have the peak rate of runoff not greater than for
the same storm under pre-development conditions.
TABLE 53-02
ALLOWABLE RELEASE AND REQUIRED
STORAGE FOR UNSTUDIED AREAS
2.0 ACRES OR LESS
Post-Developed Required Detention
Runoff Coefficient, C Storage
(cubic feet per acre)
0.3 789
0.4 1,050
0.5 1,314
0.6 1,578
0.7 1,839
0.8 2,103
0.9 2,364
1.0 2,628
(3) Stormwater detention and retention ponds which are considered
by Ohio Department of Natural Resources (ODNR) to be dam structures
shall be designed to safely pass the maximum probable precipitation
storm or flood event as defined by ODNR. Where fill berms are
proposed, calculations supporting the stability of the fill berms are to be
submitted by a geotechnical engineer. The applicant shall design all
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raised bermed stormwater ponds according to probable maximum
precipitation of flood storms (refer to Section 53.060 of the Stormwater
Regulations).
(4) If the site has multiple drainage basins, the drainage basin divides
that exist prior to development shall be used to determine pre-
development rates of discharge for each drainage area of the site.
(5) Fenced stormwater facilities are strongly discouraged within the
City and shall only be permitted if approved by the City. The City will
consider fencing stormwater facilities only where steep slopes which
potentially endanger hurnan life are unavoidable. If fencing is required,
the design shall be 6-foot high chain link fence, or better (i.e., brick wall)
along the right-of--way boundary around the entire perimeter, including
maintenance berms with access for maintenance vehicles. Other designs
may be permitted subject to the review and approval of the City Engineer.
(6) Areas adjacent to open channels and ponds shall be graded to
restrict the entrance of stormwater except at planned locations. Where
retention/detention areas are located on the project periphery, the
developer may be required to provide additional landscaping or screening
to adequately protect abutting properties.
(7) The minimum requirement for maintenance berms is as follows:
MfNINIUM MAINTENANCE
PONDS ACCESSWAY REQUIlZED
With fencing perimeter 20 feet all around
Without fencing 15 feet all around
(8) Detention/retention facilities designed to meet the requirements
of this Chapter shall also be designed to meet the erosion control
requirements of Section 53.090(G) of the Stormwater Regulations and the
stormwater runoff quality requirements of Section 53.090(H) of the
Stormwater Regulations to the extent practicable.
(9) Headwalls shall be required at all storm sewer inlets or outlets to
and from stormwater management facilities. Natural stone and/or brick
approved by the City Engineer shall be provided on all visible headwalls
and/or endwalls
(D) Storm Sewers.
(1) Storm sewers shall be designed such that they do not surcharge
from runoff caused by the 5-year, 24-hour storm, and thai the hydraulic
grade line of the storm sewer stays below the gutter flow line of the
overlying roadway, or below the top of drainage structures outside the
roadway during a 10-year, 24-hour storm. The system shall be designed
to handle the flows from the contributory area within the proposed
development.
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Ordinance No.--------------------- - ---19-------
(2) The minimum inside diameter of pipe to be used in public storm
sewer systems is 12 inches. Smaller pipe sizes may be used in private
systems, subject to the approval of the City Engineer.
(3) All storm sewers shall be designed and constructed to produce a
minimum velocity of 3.0 feet per second (fps) when flowing full. No
storm sewer system or portion thereof shall be designed to produce
velocities in excess of 10 fps, providing that the outlet ends have
sufficient energy dissipators and erosion protection.
(4) The following maximum lengths of pipe shall be used when
spacing access structures of any type:
PIPE SIZE STRUCTURE
SPACING
18 inches 300 feet
24 to 36 inches 400 feet
42 inches and larger X00 feet
(5) All storm sewer systems shall be designed taking into
consideration the tailwater of the receiving facility or waterbody. The
tailwater elevation used shall be based on the design storm frequency.
(6) The hydraulic grade line for the storm sewer system shall be
computed with consideration for the design tailwater on the system
defined in the Stormwater Master Plan and the energy losses associated
with entrance into and exit from the system, friction through the system,
and turbulence in the individual manholes, catch basins, and junctions
within the system.
(7) The minimum cover for storm sewers within the right-of--way
shall be one (1) foot measured from the top outside of pipe to the bottom
of underdrain at the back of curb. Should underdrains not be required,
the minimum cover shall be one (1) foot measured from the top outside
of pipe to the top of subgrade at the back of curb. Outside street right-of-
way, aminimum two (2) feet of cover shall be provided measured from
the top of finished ground surface to the top outside of pipe.
(8) The inverts of all curb inlets, manholes, yard inlets, and other
structures shall be formed and channelized to minimize turbulence.
(9) Storm inlets or catch basin grates shall be of a type to permit safe
crossing by bicycles as approved by the City Engineer. For the purpose
of public safety and welfare, any storm sewer outlet greater than 18
inches in diameter accessible from stormwater management facilities or
watercourses shall be provided with safety grates, as approved by the City
Engineer.
(10) The maximum distance for overland flow shall be 300 feet before
entering a storm structure. Except, that the maximum overland drainage
area tributary to the storm structure shall be no greater than 1.5 acres.
The maximum spacing of curb inlets shall not exceed 300 feet, or that
spacing which shall permit a maximum permissible spread according to
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
40-98 Passed _________19_____
Ordinance No._______.______________ _
ODOT Drainage Design Manual. Spread calculations shall be provided
with all storm drainage calculations.
(11) Headwalls shall be required at all storm sewer inlets or outlets to
and from open channels or lakes. Natural stone and/or brick approved by
the City Engineer shall be provided on all visible headwalls and/or
endwalls.
(E) Culverts and Bridges.
(1) Roadway stream crossings other than bridges shall be designed to
convey the stream's flow for the 100-year, 24-hour storm such that the
flow does not encroach upon the roadway pavement.
(2) The minimum inside diameter of pipes to be used for culvert
installations under roadways shall be 12 inches. The minimum inside
diameter of pipes to be used for driveway crossings shall be 12 inches.
(3) The maximum slope allowable shall be a slope that produces a 10-
fps velocity within the culvert barrel. Erosion protection and/or energy
dissipators shall be required to properly control entrance and outlet
velocities.
(4) All culvert installations shall be designed with consideration for
the tailwater of the receiving facility or waterbody. The tailwater
elevation used shall be based on the design storm frequency.
(5) The allowable headwater of a culvert installation should be set by
the designer for an economical installation. When end walls are used, the
headwater should not exceed the top of the end wall at the entrance. If
the top of the end wall is inundated, special protection of the roadway
embankment and/or ditch slope maybe necessary for erosion protection.
(6) The determination of the required size of a culvert installation can
be accomplished by mathematical analysis or by the use of design
nomographs.
(7) Headwalls shall be required at all culvert inlets or outlets to and
from open channels or lakes. Natural stone and/or brick approved by the
City Engineer shall be provided on all visible headwalls and/or endwalls.
(8) The minimum cover for culverts within the right-of--way shall be
one (1) foot measured from the top outside of pipe to the bottom of
underdrain at the back of curb. Should underdrains not be required, the
minimum cover shall be one (1) foot measured from the top outside of
pipe to the top of subgrade at the back of curb. Outside street right-of-
way, aminimum two (2) feet of cover shall be provided measured from
the top of finished ground surface to the top outside of pipe. The
structural design of culverts and bridges shall be the same as that required
by the Ohio Department of Transportation.
(9) Bridges shall be designed such that the hydraulic profile through
abridge shall be below the bottom chord of the bridge for either the 100-
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
40-98 Passed------- - - - ---- --
Ordinance No.--------- ---- ---- - - ----- - -- 19-
year, 24-hour storm, or the 100-year flood elevation as determined by
FEMA, whichever is more restrictive.
(F) Open Channels.
(1) Wherever possible, drainage shall be maintained by an open
channel with landscaped banks designed to carry the 10-year, 24-hour
stormwater runoff from upstream contributary areas. The City Engineer
may increase the design storm as conditions require. Channels within
FEMA floodplains shall be designed according to the requirements of
Chapter 151 of the Dublin Code of Ordinances along with the
requirements contained with this Chapter. All open channels shall be
designed with one foot of freeboard above the design water surface
elevation of the open channel flowing full.
(2) Flood relief channels shall be designed to convey the runoff from
the 100-year, 24-hour storm, such that a positive discharge of this runoff
to an adequate receiving stream or conveyance system results without
allowing this runoff to encroach into proposed or existing residential
dwellings or places of business.
(3) Roadside ditches along existing roadways may be required by the
City to be enclosed if ODOT standards for safety and maintenance cannot
be satisfied.
(G) Erosion and Sedimentation Control.
(1) All development activity greater than 2.0 acres shall be provided
with erosion and sedimentation control devices during all phases of
construction. Development activity less than or equal to 2.0 acres may
be required to have erosion and sedimentation control provided during
all construction phases if determined to be necessary by the City
Engineer.
(2) No development construction activity such as grading, cutting, or
filling shall be commenced until erosion and sedimentation control
devices have been installed to the satisfaction of the City Engineer.
(3) Stormwater discharges during the 2-year design storm shall be
released to natural channels at anon-erosive velocity of less than 3 feet
per second unless the channel is stabilized or otherwise able to withstand
higher velocities, as determined by the City Engineer.
(H) Stormwater Runoff Quality.
(1) No person shall:
(a) Construct, maintain, operate, and/or utilize any Illicit
Connection.
(b) Cause, allow or facilitate any Prohibited Discharge.
(c) Act, cause, permit, or suffer any agent, employee, or
independent contractor to construct, maintain, operate or
utilize any Illicit Connection, or cause, allow or facilitate
any Prohibited Discharge.
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98 Passed_______________
------------------- -- ---19- --
(2) Outdoor activities that, in the judgement of the City Engineer,
cannot be conducted indoors shall be conducted within specified areas of
the site designed to control stormwater quality in the following manner:
(a) Runoff from outdoor activity areas shall not be allowed to
co-mingle with runoff from the remainder of the site.
(b) Runoff from outdoor activity areas shall be directed to
separate treatment systems, as approved by the City
Engineer, able to adequately control stormwater pollutant
concentrations. These systems include, but are not
limited to the following:
1. The City's separate sanitary sewer system,
providing the discharge meets all applicable
requirements of Chapter 51 of the Dublin Code of
Ordinances.
2. An oil/water separator to remove
uncharacteristically high concentrations of oil and
grease, with treated effluent discharged to the
separate sanitary sewer system.
3. A system appropriate for the containment of
hazardous material spills, designed as specified in
Fire Prevention Code.
4. An industrial treatment system covered by a
discharge permit issued by Ohio EPA.
(3) The site shall be designed to direct runoff from areas other than
outdoor activity areas to one or more of the following stormwater quality
treatment best management practices (BMPs):
(a) Swales
(b) Filter Strips
(c) Wet detention basins
(d) Extended dry detention basins
(e) Media filters
(f) Other approved BMPs
The design stormwater quality event for these BMPs shall be the
first one-half inch of rainfall of each and every storm event. In addition,
BMPs shall be designed to accommodate flows exceeding their design
capacity, either by bypassing excess flows, conveying excess flows
through the facility without disrupting its stormwater quality control
effectiveness, or storing excess flows as necessary to achieve the
drainage, flood control, and erosion control objectives of this Chapter.
(4) Drainage areas of all swales and filter strips shall not exceed 5
acres or possess slopes greater than 2.0 percent. They shall be designed
to convey a hydrograph with the following characteristics:
V,, = A*r*a*P (acre-feet), where:
V,, =hydrograph volume, acre-feet
A =area tributary to the basin, acres
r =runoff quality coefficient = 0.85813 - 0.7812 + 0.7741 + 0.04
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98___---_-- Passed_______________
--- -- --- ------- ------ 19-----
i =impervious area ratio of the tributary watershed
a =regression constant = 1.109
P =mean storm precipitation volume = 0.04 feet
Hydrograph duration = 2 hours
Hydrograph peak shall be calculated according to the Rational
Formula methodology.
Maximum depth of flow shall be no greater than three inches.
Swales and filter strips shall be lined with fine, turf-forming,
water-resistant grasses to slow and filter flows.
(5) Wet detention basins shall consist of a permanent pool volume,
an extended detention volume of equal size, and a sediment storage
volume at least 20 percent of the volume of the permanent pool. The
permanent pool and extended detention volumes shall each be sized
according to the following equation:
Vb = A*r*a*P (acre-feet), where:
Vb =permanent pool and extended detention volumes, acre-feet
A =area tributary to the basin, acres
r =runoff quality coefficient = 0.85813 - 0.7812 + 0.7741 + 0.04
I =impervious area ratio of the tributary watershed
a =regression constant = 1.109
P =mean storm precipitation volume = 0.04 feet
The outlet shall be designed to release the entire extended
detention volume in no less than 12 hours. A valve shall also be provided
to drain the permanent pool volume for removal of accumulated
sediments. The outlet shall also be designed to minimize clogging,
vandalism, and maintenance.
The basin design shall incorporate the following features to
maximize multiple uses, aesthetics, safety, maintainability, and
compatibility with the urban landscape:
(a) Basin side slopes shall have a run to rise ration of 10:1 or
flatter to promote growth of wetland vegetation over 25 to
50 percent of the pond surface area.
(b) Basin depths in open water areas shall not exceed 12 feet
to prevent thermal stratification
(c) A forebay designed to allow larger sediment particles to
settle shall be placed at basin inlets.
(d) Astable vehicular access way shall be provided to
forebays and outlets.
(6) Extended dry detention basins shall consist of an extended
detention volume and a sediment storage volume. The extended
detention volume shall be sized according to the following equation:
Vb = A*r*a*P, where:
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98_________ Passed______________
---------------------- --19------
Vb =permanent pool and extended detention volumes, acre-feet
A =area tributary to the basin, acres
r =runoff quality coefficient = 0.85813 - 0.7812 + 0.7741 + 0.04
I =impervious area ratio of the tributary watershed
a =regression constant = 1.545
P =mean storm precipitation volume = 0.04 feet
The sediment storage volume shall be no less than 20 percent of
extended detention volume. The outlet shall be designed to release 50
percent of the extended detention volume in no less than 16 hours, and
the remainder of the extended detention volume in no less than 32 hours.
The outlet shall also be designed to minimize clogging, vandalism, and
maintenance. The basin design shall incorporate the following features
to maximize multiple uses, aesthetics, safety, maintainability, and
compatibility with the urban landscape:
(a) Basin side slopes shall have a run to rise ration of 4:1 or
flatter and vegetated to prevent bank erosion and
minimize drowning risk.
(b) A forebay designed to allow larger sediment particles to
settle shall be placed at basin inlets.
(c) Astable vehicular access way shall be provided to
forebays and outlets.
(7) Media filters shall consist of a settling basin followed by a filter
of sand, peat, or other media with a diameter between 0.02 and 0.04
inches, as approved by the City Engineer. The settling basin shall have
a settling volume of 3,600 cubic feet per acre of tributary impervious
area, a sediment storage volume of 700 cubic feet per acre of tributary
impervious area, a length to width ratio of at least 2 to 1, and a depth
between 3 feet and 10 feet. The outlet of the settling basin shall be sized
to release the entire settling basin volume within 40 hours. The filter
basin shall be designed with a surface area of 600 square feet per tributary
impervious acre, a filter depth of 1.5 feet, and a maximum water depth
above the filter surface of 6 feet.
(8) Other BMPs may be recommended to satisfy the requirements of
this Chapter if the Stormwater management plan for the site demonstrates
that these BMPs remove 85 percent of the average annual pollutant load
in runoff from the site, possess adequate provisions for long-term
maintenance, do not create a nuisance, and satisfy other sections of the
Stormwater Regulations. The Applicant shall follow to the design
guidelines found in "Rain Water and Land Development" by ODNR,
1996, and any supplemental updates thereto.
53.100 DEDICATION OF EASEMENTS AND RIGHTS-OF-WAY.
(A) Drainage easements oi~ rights-of--ways, as specified in the Stormwater
Design Standards, shall be conveyed by the applicant at no expense to the City for the
stormwater facilities within the development.
(B) When a proposed drainage system will carry water across private land
outside the development, the offsite drainage easements as specified in the Stormwater
Design Standards shall be secured by the owner or applicant.
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98 Passed_
-------19----
(C) When a development is bifurcated by a watercourse or open channel, the
applicant shall provide a drainage easement or right-of--way conforming substantially to
the lines of such watercourse or open channel, which shall be a minimum width, as
specified in this Chapter.
(D) Easements and rights-of--way shall include suitable access as specified
herein for maintenance equipment from public rights-of--ways.
(E) All drainage easements, both onsite and offsite, shall be recorded on a
final plat or a separate recorded document approved by the City.
(F) Outfall ditches, channels, and detention/retention facilities shall have
sufficient rights-of--way and/or easements for the facility plus an unobstructed
maintenance accessway on one or both sides. Said rights-of--way and/or easements shall
be contiguous to public right-of--way or easement and shall allow for suitable access by
maintenance equipment. Where the right-of--way and/or easement is provided for access
only, the minimum width shall be as follows:
DITCH OR CHANNEL
TOP OF BANK WIDTH
Less than 16 feet
16 feet to 32 feet
32 feet to 55 feet
Over 55 feet
MINIMUM MAINTENANCE
ACCESSWAY REQUIRED
20 feet one side
20 feet both sides
20 feet one side and
30 feet on the opposite side
30 feet both sides
(G) Maintenance accessways shall be sloped no steeper than 1/4-inch per foot.
Ponds shall have a sufficient right-of--way/easement to allow for installation plus an
unobstructed maintenance accessways all around the perimeter of the pond.
(H) A 20-foot easement centered on a storm sewer shall be conveyed to the
City when the storm sewer is not located within dedicated rights-of--way. Easements
shall be contiguous to public rights-of--way and shall allow for suitable access by
maintenance equipment.
(I) Overland flood routing paths shall be used to convey stormwater runoff
from the 100-year, 24-hour storm event to an adequate receiving water body, stormwater
system or stormwater detention basin such that the runoff is contained within the
easement for the flood routing path and does not cause flooding of residential or
commercial buildings or related structures. When designing the flood routing paths, the
conveyance capacity of the site's storm sewers shall be taken into consideration.
53.110 STORMWATER MANAGEMENT PLAN.
A stormwater management plan shall be prepared by the Applicant for each
proposed development activity and approved by the City Engineer if the plan
demonstrates that the proposed development activity has been planned and designed, and
shall be implemented and maintained to meet the performance criteria described herein.
Supporting calculations for each design storm specified in Section 53.090 of the
Stormwater Regulations shall be submitted and will contain, as a minimum, a runoff
hydrograph for the undeveloped and developed site, stage-storage calculations for the
detention facility, stage-discharge calculations for the outlet structure, and a runoff
hydrograph after routing through the proposed detention facility. All routing calculations
20
RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No...____40-98 Passed
-------------- -- --19 ----
shall account for tailwater conditions of the receiving facility, and shall be submitted to
the City.
(A) Stormwater Management Plan Requirements.
(1) Stormwater Management Map. The Project Engineer shall
include in the construction plans a master Stormwater management map
showing all existing and proposed features, including trees. The map is
to be prepared on a 24-inch by 36-inch sheet on a scale not to exceed 1"
= 400'. Listed below are the features that are to be included on the map.
(a) Hydrologic boundaries, including all areas flowing to the
proposed project.
(b) Project boundaries and area.
(c) Sufficient topographical information with elevations to
verify the location of all ridges, streams, etc. (one-foot
contour intervals within the project's boundaries and for
proposed offsite improvements).
(d) High water data or critical flood elevations on existing
structures upstream of, within, and downstream of the
project.
(e) Notes indicating sources of high water data and critical flood
elevations.
(f) Notes pertaining to existing standing water, areas of heavy
seepage, springs, wetlands, streams, and hydrologically
sensitive areas.
(g) Existing Stormwater management features (ditches, pipes,
roadways, ponds, and BMPs). Existing stormwater
management features are to be shown a minimum of 1,000
feet downstream of the proposed development unless the
ultimate outfall system is a lesser distance.
(h) Subdivision layouts with horizontal and vertical controls.
(i) Proposed and existing stormwater management features,
including locations of inlets, swales, pipes,
detention/retention facilities, BMPs, ponding areas, and all
works.
(j) Delineation and area of pre-development and post-
development sub-basins.
(k) Delineate retention/detention facilities and ingress/egress
areas for facilities maintenance.
(1) General type of soils by sub-basin and location of soil
borings.
(m) 10-, 25-, and 100-year flood elevations for any areas in or
within 100 feet of the property. The source of these
elevations shall also be shown on the plans.
(n) Description of current ground cover, land use, and
imperviousness by sub-basin.
(2) Stormwater Calculations. Stormwater calculations, sealed by a
Professional Engineer for all stormwater works, including design high
water elevations for all applicable storm events shall include the
following:
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98 Passed_
-------19----
(a) Pre- and post-development stormwater flows and stages for
the site and retention/detention ponds for all design storm
frequencies pertinent to the project based upon the
requirements of the Stormwater Regulations, including, but
not limited to, the following:
1. Pre-development hydrograph, post-development runoff
hydrograph to the stormwater pond, and the routed
post-development hydrograph discharged from the
stormwater pond.
2. Pre-development and post-development runoff
volumes.
3. Stage-area-storage calculations for the stormwater
pond.
4. Stage-discharge calculations for the outfall control
structure, including tailwater assumptions.
5. Stormwater quality control BMP volumes and recovery
calculations.
6. Soil storage or curve number calculations per sub-
basin, including impervious calculations.
7. Time of concentration calculations per sub-basin.
8. 100-year floodplain compensating calculations, if
applicable.
(b) Storm sewer, culvert, open channel and BMP tabulations,
including, but not limited to, the following:
1. Location and type of structures.
.2. Length of facility and dimensions, including diameter,
height, and/or width for pipes.
3. Cross-sections for open channels.
4. Sub-basin areas tributary to each structure.
5. Runoff coefficient or curve number per sub-basin.
6. Time of concentration to the inlet of each structure.
7. Each stormwater flow to and from the stormwater
structure or junction point.
8. Hydraulic gradient for the applicable storm event,
including losses through structures with friction and
local loss coefficients.
9. Estimated receiving water elevation with sources of
information, if available.
10. Velocities for all facilities and details for provisions to
control erosion.
(c) Construction plans including, but not limited to, the
following:
1. Overall project plan of roads, lots, and retention or
detention facilities.
2. Cross-section of retention/detention facilities and
BMPs.
3. Typical swale, ditch, or canal sections.
4. Drainage rights-of--way.
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98 Passed 19
5. Road plan and profile with groundwater elevation
shown in profile.
6. An erosion control plan.
7. Overall project grading plan (at 1-foot contours) and
individual lot grading plans.
8. Density of the project.
53.120 STORMWATER MANAGEMENT PLAN APPLICATION.
(A) It is strongly recommended that the Applicant and the Project Engineer
meet with City staff prior to generating detailed design calculations and construction
drawings in order to review and plan design requirements for a particular project.
(B) It is the responsibility of the Applicant to include in the stormwater
management plan application sufficient information for the City to evaluate:
(1) The environmental and hydraulic characteristics of the affected
areas;
(2) The potential and predicted impacts of the proposed activity on
community waters;
(3) The effectiveness and acceptability of those measures proposed by
the Applicant for eliminating or reducing adverse impacts; and
(C) The stormwater management plan application shall contain:
(1) The name, address, and telephone number of the Owner and
Applicant, and the entity that will maintain the system;
(2) The maps, charts, graphs, tables, photographs, narrative
descriptions, explanations, and citations to support references, as
appropriate to communicate the information required by this Chapter; and
(3) Construction plans and specifications for all components of the
stormwater management system shall be included in the stormwater
management plan application, which shall be prepared or directly
supervised by, signed, and sealed by a Professional Engineer.
53.130 ACCEPTANCE OF STORMVVATER IlVIPROVEMENTS.
Subsequent to the Applicant satisfying the requirements of the stormwater
Regulations and other applicable Ordinances, and the issuances of appropriate permits
and/or approvals, the Applicant shall, during construction, arrange for and schedule the
following inspections by the City.
(A) During clearing operation and excavation to assure that effective control
practices relative to erosion and sedimentation are being followed.
(B) All public underground conveyance and control structures prior to
backfilling, and all taps of private underground conveyance systems into public
conveyance systems.
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98 Passed_
---------19-----
(C) Final inspection when all public systems required under the approved
stormwater management plan have been installed.
(D) The Professional Engineer for the project shall submit a signed and sealed
set of as-built plans, on electronic disk and reproducible mylar brand polyester film
drawing sheets, to certify the system has been constructed as designed and satisfies all
conditions of the stormwater management plan. Where changes have been made to the
stormwater management system which deviate from the approved construction plans, the
Professional Engineer shall submit supporting documentation with the as-built plans,
which proves that the stormwater system shall be in compliance with the Stormwater
Regulations
(E) Maintenance and compliance inspections of stormwater management
systems shall be conducted on a routine, periodic basis, as deemed appropriate by the
City, or as complaints arise concerning the system. By seeking and obtaining plan
approval under the Stormwater Regulations, the operator and owner shall be deemed to
have consented to inspections by the City and other appropriate regulatory agencies or
departments upon presentation of proper identification by the representative(s) of the
agency(ies) conducting the. inspections.
(F) Public Improvements. Public stormwater conveyance and control systems
may be accepted for public use after the following minimum conditions have been met:
(1) The Applicant shall provide to the City Engineer security according
to Section 152.045 of the Dublin Code of Ordinances;
(2) The Applicant shall provide to the City Engineer as-built plans
according to Section 53.140(D) of the Stormwater Regulations; and
(3) The as-built plans have been reviewed and approved by the City
Engineer.
(G) Private Improvements. Private stormwater conveyance and control
systems maybe approved for use after the following minimum conditions have been met:
(1) The Applicant shall provide to the City Engineer as-built plans
according to Section 53.140(D) of the Stormwater Regulations; and
(2) The as-built plans have been reviewed and approved by the City
Engineer. Until said as-built plans have been approved, no conditional
occupancy or final permit occupancy permit shall be issued.
53.140 MAINTENANCE RESPONSIBILITY.
(A) The installed stormwater system shall be maintained by the legal entity
responsible for maintenance. All stormwater management plan applications shall contain
documentation sufficient to demonstrate that the operation and maintenance entity is the
legal entity empowered and obligated to perpetually maintain the stormwater
management facilities. The City considers the following entities acceptable to operate
and maintain stormwater management facilities:
(1) Local governmental units, including the County, municipalities, or
Municipal Service Taxing Units.
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98 Passed
----------------------19- ---
(2) Non-profit corporations, including homeowners associations,
property owners associations or condominium owners associations, under
certain conditions which ensure that the corporation has the financial,
legal, and administrative capability to provide for the long-term operation
and maintenance of the facilities.
(3) The property owner or developer is normally not acceptable as a
responsible entity, especially when the property is to be sold to various
third parties. However, the property owner or developer may be
acceptable under one of the following circumstances:
(a) The property is wholly owned by said Applicant and the
ownership is intended to be retained. This would apply to a
.farm, corporate office, or single industrial facility, for
example.
(b) The ownership of the property is retained by the Applicant
and is either leased to third parties (such as in some shopping
centers), or rented to third parties (such as in some mobile
home parks), for example.
(B) The stormwater management system to be maintained by the legal entity.
Public improvements shall have adequate easements, in accordance with Section 53.100
of the Stormwater Regulations, to permit the City to inspect, and if necessary, to take
corrective action should the legal entity fail to maintain the system properly.
(C) Maintenance of stormwater facilities shall allow the stormwater
management system to perform as originally designed and permitted by the City and
other appropriate governmental agencies and as set forth in the written plan.
(D) Maintenance shall include compliance with City building and construction
codes, and all other applicable codes.
53.150 ENFORCEMENT.
If at any time the City Engineer determines that the project is not in accordance
with the approved plan, or if any project subject to the Stormwater Regulations is being
carried out without an approved plan, the City Engineer is authorized to:
(A) Give the legal entity written notice of the corrective action required to be
taken. Should the legal entity fail within thirty (30) days of the date of the notice to
complete such corrective action, the City Engineer may enter upon the property, take the
necessary corrective action, bill the violator, and if the bill is not paid within ninety (90)
days, file a lien upon the property for the cost of such corrective action.
(B) Take appropriate corrective action in the event of an emergency situation
which endangers persons or property, or both, as determined to exist by the City
Engineer.
(C) Issue written notice to the Applicant specifying the nature and location
of the alleged noncompliance, with a description of the remedial actions necessary to
bring the project into compliance within five (5) working days.
(D) Issue astop-work order directing the Applicant or persons in possession
to cease and desist all or any portion of the work which violates the provisions of the
25
RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No._____40-98______.___ Passed_______________
---------------19-----
Stormwater Regulations if the remedial work is not completed within the specified time.
The Applicant shall then bring the project into compliance.
53.160 SEVERABII.ITY.
If any section, sentence, clause or phrase of the Stormwater Regulations is held
to be invalid or unconstitutional by any court of competent jurisdiction, then said holding
shall in no way affect the validity of the remaining portions of the Stormwater
Regulations.
53.170 EFFECTIVE DATE.
The Stormwater Regulations shall take effect and be in force from and after the
earliest date permitted by law.
53.999 PENALTY.
Whoever violates any provisions of this Chapter is guilty of an unclassified
misdemeanor with a maximum fine of $2, 500 and/or 6 months in j ail with each day of
violation as a separate offense.
SECTION 2. To Amend Section 152.002 of the Dublin Code of Ordinances as
follows:
SECTION 3. To Amend Section 152.050 of the Dublin Code of Ordinances as
follows:
The design of stormwater runoff conveyance systems including, but not
limited to storm sewers and appurtenant structures, bridges, culverts, ditches,
swales, detention and/or retention facilities, shall meet the requirements of Chapter
53 of the Dublin Code of Ordinances.
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No.----- 40-98--------- Passed- ----- -- -- ----- ----------------
--------------19---- -
ate:
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RECORD OF ORDINANCES
Dayton Legal Blank Co. Form No. 30043
Ordinance No.____40-98_______..__ Passed_______._______
------------------ - - 19- --
SECTION 4. That this Ordinance be, and the same hereby is, declared to be an
emergency measure for the preservation of the public peace, health and welfare of the
residents of this City, and therefore this Ordinance shall take effect and be in force
immediately upon its passage.
Attest:
Clerk of Council
1998.
SPONSOR: City Engineer /Director of Engineering
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