A. Stormwater Pollution Prevention Plan (SWPPP): A SWPPP shall be submitted for review and approval by the City Engineer for projects disturbing one acre or more of land. The plan should be prepared by a qualified individual, conform to the MPCA's current Construction Stormwater Permit (MNR100001), and incorporate the appropriate Best Management Practices (BMPs) described in the "Minnesota Stormwater Manual". The SWPPP shall include:
1. Project Description: Project description including the nature and purpose of the land disturbing activity and the amount of grading, utilities, and building construction involved.
2. Project Phasing Plan: Project phasing plan including the time frames and schedules for the project's various aspects.
3. Map: A map of the existing site conditions: existing topography, property information, steep slopes, existing drainage systems/patterns, type of soils, waterways, wetlands, vegetative cover, and 100-year floodplains.
4. Site Construction Plan: A site construction plan that includes the proposed land disturbing activities, soil stockpiles, erosion and sediment control plan, construction schedule, and the maintenance and inspection of the stormwater pollution prevention measures.
5. Adjacent Areas: Adjacent areas, neighboring streams, lakes, residential areas, roads, etc., within one hundred feet (100') of the subject site, which may be affected by the land disturbing activity.
6. Methods Of Control: The methods that will be used to control erosion and sedimentation on the site, both during and after construction, including the following items:
a. Schedule and methods to stabilize all exposed soils, soil stockpiles and steep slopes.
b. Schedule and methods to establish permanent vegetation.
c. Methods to prevent sedimentation damage to adjacent properties and natural features.
d. Measures to control the quality and quantity of stormwater leaving the site.
e. Methods to protect storm sewers from the entrance of sediment.
f. Methods to protect paved roads from sediment and mud brought in from access routes.
g. Methods to maintain both temporary and permanent erosion and sediment control devices.
h. Methods to restabilize utility construction areas as soon as possible.
i. Calculations and design parameters for sediment basins, wet detention basins, diversions, waterways, and other applicable practices.
7. Waste And Material Collection And Disposal: All waste and unused building materials (including garbage, debris, cleaning wastes, litter, wastewater or sewage, toxic materials or hazardous materials) shall be properly contained while on site, properly disposed of off-site, and not allowed to be carried by water and/or wind off the site or into a receiving channel or storm sewer system. Waste containers and all construction materials shall not be placed or stored such that they obstruct, encroach upon, or interfere wholly or in part with any public right-of-way, including but not limited to, public roadways, trails, sidewalks, parks or other public properties.
B. Minimum SWPPP Requirements: The Construction Stormwater Permit (MNR100001) SWPPP requirements shall be followed along with the following minimum control measures where bare soil is exposed. Due to the diversity of individual construction sites, each site will be individually evaluated. Where additional control measures are needed, they will be specified at the discretion of the City Engineer.
1. A structure with a three foot (3') sump for collecting coarse grained material shall be provided with new storm sewer systems. The sump catch basin or manhole shall be located within the street and just prior to discharge into a water body. Such basins shall be cleaned when they are half filled with material.
2. All stormwater pollution control management facilities shall be designed to minimize the need of maintenance, to provide easy access for maintenance purposes and be structurally sound. These facilities shall have a plan of operation and maintenance that ensures continued effective removal of the pollutants carried in stormwater runoff. The City or its designated representative shall inspect all stormwater management facilities as part of the normal maintenance program for public works facilities. It shall be the responsibility of the applicant to obtain any necessary easements or other property interests to allow access to the stormwater management facilities for inspection and maintenance purpose.
3. If a stormwater management plan involves directing some or all runoff from the site, the applicant shall obtain from adjacent property owners any necessary easements or other property interests concerning flowage of water.
4. Stormwater pollution controls shall be installed on all down gradient perimeters before commencing the land disturbing activity, and shall not be removed without City approval. Upon City acceptance of turf establishment and other such permanent erosion control measures, the owner shall remove all silt fence and other temporary erosion control measures.
5. Slopes greater than four to one (4:1) shall have erosion control blanket installed immediately after finished grading. (Ord. 2018-03, 1-16-2018; amd. Ord. 2023-03, 3-20-2023)