Subd. 1. Established. This section shall be known as the “Construction Site Erosion and Sediment Control Ordinance” of the city and may be so cited.
Subd. 2. Introduction; Purpose.
A. During the construction process, soil is highly vulnerable to erosion by wind and water. Eroded soil endangers water resources by reducing water quality and causing the siltation of aquatic habitat for fish and other desirable species. Eroded soil also necessitates repair of sewers and ditches and the dredging of lakes. In addition, clearing and grading during construction cause the loss of native vegetation necessary for terrestrial and aquatic habitat.
B. As a result, the purpose of this local regulation is to safeguard persons, protect property, and prevent damage to the environment in the city. This section will also promote the public welfare by guiding, regulating, and controlling the design, construction, use, and maintenance of any development or other activity that disturbs or breaks the topsoil or results in the movement of earth on land in the city.
C. This section is not to serve as a replacement for the regulations set forth by the Minnesota Pollution Control Agency (MPCA) or U.S. Environmental Protection Agency (EPA) regarding construction activity stormwater permitting. In the event that any regulation contained in this section conflicts with a corresponding MPCA and/or EPA regulation, the more stringent or restrictive regulation will be upheld.
Subd. 4. Permits.
A. No person shall be granted a site development permit for land-disturbing activity that would require the uncovering of 43,560 or more square feet, or less than that area but that are part a larger common plan of development or sale, without the approval of a Stormwater Pollution Prevention Plan (SWPPP) by the Engineering or Building Department.
B. No site development permit is required for the following activities:
1. Any emergency activity that is immediately necessary for the protection of life, property, or natural resources;
2. Existing nursery and agricultural operations conducted as a permitted main or accessory use; and/or
3. Subdivision, road, or utility construction that will be inspected by the Engineering Department.
C. Each application shall bear the name(s) and address(es) of the owner or developer of the site, and of any consulting firm retained by the applicant together with the name of the applicant's principal contact at such firm and shall be accompanied by a fee as established by the city.
D. Each application shall include all MPCA construction activity stormwater permit application documents, including a completed Stormwater Pollution Prevention Plan.
E. Each application shall include a statement that any land clearing, construction, or development involving the movement of earth shall be in accordance with the SWPPP and that a certified contractor shall be on site on all days when construction or grading activity takes place.
Subd. 5. Review and Approval.
A. The city will review each application for a site development permit to determine its conformance with the provisions of this regulation. Within 15 days after receiving an application, the city shall respond to the applicant if:
1. The application is not approved;
2. The application is approved, pending conditions.
B. No response by the city on an original or revised application within 15 days of receipt shall authorize the applicant to proceed in accordance with the plans as filed unless such time is extended by agreement between the applicant and the city. Pending preparation and approval of a revised plan, development activities shall be allowed to proceed in accordance with conditions established by the city.
Subd. 6. Stormwater Pollution Prevention Plan (SWPPP).
A. The Stormwater Pollution Prevention Plan shall include the following:
1. A natural resources map identifying soils, forest cover, and water resources located on or near the site;
2. A sequence of construction of the development site, including stripping and clearing; rough grading; construction of utilities, infrastructures, and buildings; and final grading and landscaping. Sequencing shall identify the expected date on which clearing will begin, the estimated duration of exposure of cleared areas, areas of clearing, installation of temporary erosion and sediment control measures, and establishment of permanent vegetation;
3. All erosion and sediment control measures necessary to meet the objectives of this local regulation throughout all phases of construction and after completion of development of the site. Depending upon the complexity of the project, the drafting of intermediate plans may be required at the close of each season;
4. Seeding mixtures and rates, types of sod, method of seedbed preparation, expected seeding dates, type and rate of lime and fertilizer application, and kind and quantity of mulching for both temporary and permanent vegetative control measures;
5. Waste controls for any type of waste which may be generated on the site. Waste controls must provide for appropriate waste storage on-site and property disposal;
6. Provisions for maintenance of control of facilities, including easements and estimates of the cost of maintenance;
7. A statement indicating the party responsible for the long-term stormwater management for the development and the party responsible for any permanent stormwater management systems on site; and
8. Modifications to the plan shall be processed and approved or disapproved in the same manner as Subd. 5 of this regulation, may be authorized by the city by written authorization to the permittee, and shall include:
A. Major amendments of the SWPPP submitted to Inspection Department;
B. Field modifications of a minor nature.
Subd. 7. Design Requirements.
A. Grading, erosion control practices, sediment control practices, and waterway crossings shall be at least as stringent as the MPCA's General Permit to Discharge Stormwater Associated with Construction Activity No. MNR100001 (Part IV: Construction Activity Requirements) and shall be adequate to prevent transportation of sediment from the site to the satisfaction of the city. Recommended Best Management Practices (BMPs) are those in the latest version of the Minnesota Stormwater Manual.
B. Clearing and grading of natural resources, such as forests and wetlands, shall not be permitted, except when in compliance with all other requirements and all applicable state and federal laws. Clearing techniques that retain natural vegetation and drainage patterns, as described in the Minnesota Stormwater Manual, shall be used to the satisfaction of the city.
C. Clearing, except that necessary to establish sediment control devices, shall not begin until all sediment control devices have been installed and have been stabilized.
D. Erosion control requirements shall include the following:
1. Soil stabilization shall be completed within five days of clearing or inactivity in construction;
2. If seeding or another vegetative erosion control method is used, it shall become established within two weeks or the city may require the site to be reseeded or a non-vegetative option employed;
3. Special techniques that meet the design criteria outlined in the Minnesota Stormwater Manual on steep slopes or in drainage ways shall be used to ensure stabilization;
4. Soil stockpiles must be stabilized or covered at the end of each workday. The entire site must be stabilized, using a heavy mulch layer or another method that does not require germination to control erosion, at the close of the construction season;
5. Techniques shall be employed to prevent the blowing of dust or sediment from the site;
6. Techniques that divert upland runoff past disturbed slopes shall be employed.
E. Sediment control requirements shall include:
1. Settling basins, sediment traps, or tanks and perimeter controls;
2. Settling basins that are designed in a manner that allows adaptation to provide long-term stormwater management, if required by the city;
3. Protection for adjacent properties by the use of a vegetated buffer strip in combination with perimeter controls.
F. Waterway and watercourse protection requirements shall include:
1. Stabilization of the watercourse channel before, during, and after any in-channel work;
2. On-site stormwater conveyance channels designed according to the criteria outlined in the Minnesota Water Manual; and
3. Stabilization adequate to prevent erosion located at the outlets of all pipes and paved channels.
G. Construction site access requirements shall include:
1. A temporary rock construction entrance provided at all sites. Rock shall be crushed 1-1/2 inch diameter, minimum. The dimensions shall be 20 feet by 50 feet with a depth of at least nine inches;
2. Other measures required by the city in order to ensure that sediment is not tracked onto public streets by construction vehicles or washed into storm drains.
H. Post-construction stormwater management BMPs in accordance with § 20.06.
Subd. 8. Inspection.
A. The City shall make inspections as hereinafter required and either shall approve that portion of the work completed or shall notify the permittee wherein the work fails to comply with the SWPPP as approved. Plans for grading, stripping, excavating, and filling work shall be maintained at the site during the progress of the work. The permittee shall notify the city at least two working days before the following:
1. Start of construction;
2. Completion of site clearing;
3. Completion of final grading; and
4. Completion of final landscaping.
B. The permittee shall make regular inspections per the requirements of the MPCA construction activity stormwater permit.
C. The city or its designated agent shall enter the property of the applicant as deemed necessary to make regular inspections.
Subd. 9. Small Construction Sites.
A. All construction activities which disturb less than one acre of land, and that are not part of a larger plan of development or sale, are considered “small construction sites” and are required to have the following erosion and sediment control BMPs in place:
1. Perimeter control. Down gradient silt fence or other approved method as listed in the Minnesota Stormwater Manual.
2. Vehicle tracking control. Rock or wood mulch construction entrance measuring at least eight feet wide and 20 feet long. All construction access and egress shall be through this entrance.
3. Stockpile control. All soil stockpiles not being actively used shall be either covered with an impermeable sheet or protected by silt fence, no further than three feet from the base of the stockpile.
4. Turf establishment. Upon completion of final topsoil grading and seeding, the soil shall be covered with straw mulch (disked in), liquid tackifier, or erosion control blanket. Perimeter controls shall remain in place until this is completed.
5. Good housekeeping. Any sediment that is transported off-site shall be cleaned up and replaced on the site within 24 hours of discovery. This includes any sediment in the roadway or gutter.
B. A plan shall be submitted to the city which addresses the details and locations of the items listed in Part A.1. through 5. of this subdivision, above.
C. Erosion and sediment control on small construction sites is the responsibility of the general contractor for the site. In the event that there is no general contractor for the site, the landowner becomes responsible.
D. Exemptions. Activities disturbing less than 2,500 square feet of soil are exempt from the requirements set forth in this section.
(Ord. 622, passed 12-1-14)