Welcome to your online guide to the City of D’Iberville stormwater management plan. The information in this section of the city’s web site is part of the city’s continuing effort to educate the public about the importance of protecting water quality through land use and natural resource planning.
The city’s stormwater management plan, which is mandated by the Department of Environmental Quality, is designed to help protect and improve water quality, which can be jeopardized by pollution carried by stormwater runoff. The program has been developed in a collaborative effort with nearby cities of Gulfport, Biloxi, Long Beach, Pass Christian, and Harrison County. The plan is called Stormwater Phase II.
The specific issues to be addressed:
- 1. General Stormwater Runoff Pollution
- 2. Illegal Dumping and Improper Disposal of Household Hazardous Wastes, Automobile Wastes and Disposal of Litter and Debris
- 3. Erosion and Sedimentation Associated with Construction and Development
- 4. Leaking Individual On-site Wastewater Treatment Systems and Sewage Pollution
The program components include Public Education, Public Involvement, Illicit Discharges Detection and Elimination, Construction Site Runoff Controls, Post-Construction Runoff Controls, and Pollution Prevention/Good Housekeeping.
The contact person for D’Iberville stormwater runoff management is Bobby Simmons, who can be reached at (228)860-2897 or by email at firstname.lastname@example.org
Here are some websites that can provide additional information on stormwater runoff pollution.
EPA’s Non Point Source Pollution Page – [Website]
The EPA’s website provides links to information and resources in a number of categories including publications, training and meetings, applicable regulations. Contains fact sheets, articles, and resources that define Non Point Source Pollution (NPS) and how it can be prevented or reduced. Topics include household chemicals, septic systems, and impervious surfaces. This site also includes links to the Non Point Source Kids Page that contains games, puzzles, interactive activities, and education materials.
Mississippi Department of Marine Resources – [Website]
The Department of Marine Resources website has a wealth of information for the public, with some info specifically targeted to children, teachers, boaters, marinas, etc. Information includes pollution prevention, non-point source pollution, stormwater runoff management and best management practices provided by Mississippi Gulf Coast Stormwater Management Toolbox, stormwater management tools for schools, Coastal Cleanups and workshop information for teachers.
Mississippi Department of Environmental Quality – [Website]
NonPoint Source Education Page
The MDEQ site contains links to information related to a variety of public education, outreach, and involvement programs that are available through MDEQ. These programs include information for teachers, students, volunteer groups, homeowners, volunteer groups, and stormwater management officials.
Urban Stormwater and Construction – [Website]
This site contains a narrative description of urban stormwater impacts including those resulting from construction. Provides links to stormwater permit information and BMP design manuals for construction. It is targeted to the construction industry, stormwater managers, and the public.
Non-Point Source Pollution Literature and Publication – [Website]
This webpage contains links to MDEQ-sponsored literature and publications on non point source pollution, targeted to the public, construction industry and stormwater managers.
Mississippi Stormwater Pollution Prevention Plan Guidance Manual for Construction Activities – [Website]
This booklet provides a guide for developing a Storm Water Pollution Prevention Plan (SWPPP) for the Mississippi Department of Environmental Quality (MDEQ) as required in the state’s Construction Storm Water General NDPES Permit
MS State University Extension Service – [Website]
This website contains numerous fact sheets on the Correct Use of Your Septic Tank, Control of Garden Bugs, Household Cleaning Products, Maintaining a Sanitary Septic System, Lawn Mulching for Homeowners, and Non-Chemical Weed Control.
Planning & Design Manual for the Control of Erosion, Sediment & Storm Water – [Website]
This manual provides technical guidance for the control of erosion, sediment, and stormwater from non-point sources and for the preparation of erosion, sediment, and stormwater control plans as needed. The manual is a cooperative effort by: Mississippi Department of Environmental Quality, Mississippi Soil & Water Conservation Commission and the USDA Soil Conservation Service.
City of D’Iberville Storm Water Management Ordinance:
311 – Stormwater Sewer System
311.1 A subsurface stormwater sewer system, including drainage culverts, inlets, catch basins, junction boxes and all other necessary components shall be installed by the developer throughout the proposed subdivision.
311.1.1 The entire storm drainage system should be designed to carry not less than the stormwater from a rainfall expected to occur once in twenty-five (25) years with a runoff factor calculated on the basis of topography and percolation test subject to the approval of the city and consistent with the City’s current stromwater management plan.
311.1.2 Erosion, sediment, and stromwater controls consistent with guidance from the Mississippi Department of Environmental Quality shall be incorporated into the design.
311.1.3 Stormwater controls shall limit the rate of discharge from the property to the pre-development flow rate unless otherwise approved by the Building Official.
311.1.4 In no case shall ditches be permitted without the prior approval of the Building Official.
311.1.5 The length of a swale shall not exceed three hundred (300) feet unless approved by the Building Official. Maintenance of swales shall not be the responsibility of the City of D’Iberville.
311.2 Areas subject to ponding or inundation must be indicated on the preliminary and final plats. In as much as Federal and Mississippi State Law, regulations and procedures allow, provisions must be made to eliminate the ponding before the Planning Commission recommends approval of the plat to the Mayor and Council.
311.3 No property proposed to be subdivide within the City of D’Iberville will be allowed to be filled, graded, cleared or contoured, nor shall any other action be taken thereon whereby the surface drainage from said property will be created, increased, redirected, re-routed, funneled, dispersed, or otherwise affected unless and until all requirements and provisions of his Ordinance are fully complied with. Provided, however, if the property in question is less than 2,500 square feet in size or the amount of fill or grading involved is, in total, less than 5 cubic yards, the provisions of this section shall not apply, unless such area will affect any natural drain.
311.4 Prior to any work being done falling within the provision of these regulations, preliminary plat approval shall first be obtained from the Mayor and Council of the City of D’Iberville, Mississippi.
311.4.1 A storm Water Pollution Prevention Plan (SWPPP) shall be included in the plans.
a. A copy of MDEQ approval shall be submitted if the parcel is over five acres.
b. A copy of the pre and post development and retention/detention pond calculations shall be submitted if the parcel is over two acres.
311.5 Should the City determine that the proposed subdivision significantly impacts the existing upstream or downstream stormwater drainage system and requires the capacity of the City’s stormwater drainage system to be increased in any way, the City shall estimate the total cost of same including any city costs for engineering.
311.5.1 This cost shall be prorated by the percentage of increased drainage used by the developer’s proposed subdivision.
311.5.2 Should the developer agree, upon payment of such cost to the City, the Building Official will favorably recommend the stormwater drainage system during the review and approval process for preliminary plat.
311.5.3 Should the developer disagree, these figures will be submitted to the Planning Commission for review and recommendation to the Mayor and Council for their decision as to:
a. If the developer should be required to pay any fee.
b. The amount of the fee that should be paid to the city to offset the impact of such city drainage.
c. If additional drainage capacity is provided in enlarging the drainage system, that any other developers/builders in the area will also pay a percentage based upon the increased drainage used by them. Upon decision by the Mayor and Council, the developer shall pay the fee required by the City, prior to preliminary plat approval.
311.6 Should applicant be aggrieved by the decision of the Mayor and Council, he may appeal such decision to the Circuit Court of Harrison County, Mississippi, in the time and manner prescribed by law.
311.7 The impact of development on the off-site upstream and downstream drainage will be calculated.
311.7.1 Calculations will be provided prior to preliminary plat approval.
311.7.2 Development shall in no way be an obstruction to natural or existing drainage.
311.7.3 The City will determine how far upstream and downstream that the developer’s engineer must evaluate the impact of the proposed subdivision’s off-site drainage.
311.8 The grading and drainage plan will show the existing and general proposed finished grading of each lot, as well as proposed finished floor elevation for each lot. Erosion, sediment, and stormwater controls consistent with guidance from the Mississippi Department of Environmental Quality (MDEQ) shall be incorporated into the design. Stormwater controls shall limit the rate of discharge from the property to the pre-development flow rate unless otherwise approved by the Building Official.
311.9 Storm drainage improvements will consist of adequate pipes, catch basins and curb inlets. Corrugated metal will not be acceptable. Construction of any new open ditches will not be allowed. Only existing natural drains that already run through the development may be re-utilized in the overall subdivision drainage plan unless a special variance is granted by the Mayor and Council after review and findings by the Planning Commission. However, swales as defined in paragraph 311.7, may be used to a limited extent.
311.10 Drainage of storm water will not be allowed to cross the center line of any street as it flows over the street pavement surface. Gutter flow lines must drain into a curb inlet or catch basin and the use of flumes through the back of curbs will not be allowed. Alleys may be utilized for the conveyance of storm water provided the anticipated volume of flow and depth of flow is indicated on the drainage plan and approved by the City.
311.11 Catch basins and curb inlets will be spaced at an approximate distance to ensure that water in the gutter will not be more than eight (8) feet into the street measured from the back of the gutter. Curb inlets shall not have more than a seven (7) inch vertical opening and shall not cause a hazard to pedestrians. Junction boxes, curb inlets, and catch basin sizes and openings shall be designed to be of sufficient capacity to handle the amount of stormwater drainage into it and shall in no way cause a restriction to the amount of drainage going through the inlet or outlet pipes at that respective location.
311.12 The outlet ends of culverts will terminate with a flared end section or head-wall with a slope to the top of the bank above the outlet of a minimum of three (3) feet horizontally to one (1) foot vertically. The outlet ends of culverts will also have permanent erosion control and dissipaters as well as provisions to prevent sedimentation of downstream drainage-ways during subdivision construction and development on each lot.
311.12.1 Stream or ditch banks opposite of an outfall structure shall be armored with rip-rap or an approved equivalent material to prevent erosion.
311.13 The stormwater sewer system design and plans shall include the following:
311.13.1 The proposed finish invert elevations will be shown at the inlets, outlets and at any changes in slopes.
311.13.2 Catch basin or curb inlet elevations will be shown.
311.13.3 Calculations will be provided for the amount of rainwater runoff, based on a 25-year flood storm frequency, and required sizes, slopes and actual capacity for all culverts and ditches to handle this runoff.
311.13.4 Any storm drain system installed within the city’s right-of-way must consist of reinforced concrete pipe.
311.13.5 Existing and proposed ditch cross sections in natural drainage areas will be provided.
311.13.6 All drainage structures (inlets, head-walls, and manholes) shall be numbered on the plans.
311.13.7 All ditches, where allowed, shall be lined with rock when discharging into the City of D’Iberville drainage system.
311.14 Subdivision drainage shall be designed in a manner where the site drains to existing storm drain structures. Should additional drainage structures be required, the proposed drainage shall be placed underground in pipes if al all possible and placed in a permanent drainage easement.
311.14.1 Drainage easements shall be kept clear of all items which could adversely affect the drainage. If items such as fences, landscaping material, and other appurtenances installed by the property owner in the easement must be removed by the city to service the drainage system, the cost of removal and replacement shall be the responsibility of the property owner.
311.15 The owner/developer shall compile a video library of the upstream and downstream suctions of each storm drain tap. The existing drainage pipe shall be video taped from the point of new connections to the nearest inlet in either direction, but shall not exceed three hundred (300) feet. When completed the video tape files shall be submitted to the City Building Official.
311.16 All drainage pipe located underneath any existing or future public roadway shall be RCP.