Updated: Sep 9, 2021
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According to MDEQ, erosion and sedimentation are separate but inter-related processes.
- Erosion: the process by which soil particles are dislodged by the action of wind, water, ice, or gravity and set into motion.
- Sedimentation: the process whereby detached particles generated by erosion are deposited elsewhere on the land or in waterways.
- Accelerated soil erosion: the increased loss of the land surface that occurs due to human activities.
Contractors and developers are responsible for installing, maintaining, and removing temporary SESC measures when ground cover is disturbed. Even if the City determines that a soil erosion and sediment control permit is not required, you must still comply with the requirements of Part 91 during any construction-related activity.
Applicants must install temporary SESC measures prior to construction, request an initial inspection before breaking ground, and follow the city's procedures for obtaining a Certificate of Occupancy and permit closure.
NOTE: Your site is NOT in compliance with your permit if the controls on your approved plan are not properly installed or sediment leaves the site due to tracking or accelerated erosion.
For permitting information, contact - Building Department 248.530.1850. To schedule inspections, call 248.530.1840.
The Savings of Compliance
Controlling erosion and sediment is often thought of as an unnecessary expense, but maintaining permit compliance by keeping sediment off streets and out of storm sewers and waterways can lead to cost savings that you may not have considered.
- Sites typically pay 2 to 3 times as much in inspection fees when not in compliance.
- Avoid citizen complaints, inspection delays, downtime, and Stop Work Orders.
- Erosion control is much more cost-effective than reacting to sediment with sediment control measures, but both are less costly than dredging and restoration of lakes, streams, and wetlands.
- Studies have shown that developers who landscape their right-of-ways and seed and mulch shortly after paving the roads are able to sell lots for a significant return on investment.
- Erosion control practices can conserve valuable topsoil.
- Minimize the duration of earth disturbance to reduce inspection and cleanup costs.
- Avoid the costs of structural repairs, flooding, and sediment removal from channels, sewers and catchbasins.
- Protect public health and safety by controlling dust, cleaning streets, and removing construction debris.
- Part 91, Section 9119, allows the City to 'enter upon the land and construct, implement, and maintain soil erosion and sedimentation control measures'. It is less expensive to maintain controls yourself.
- Timely stabilization of critical areas is less expensive than repairing slope failures and gully erosion.
- Protect and enhance waterways as an amenity to increase property values.
- Bill 651 was recently passed which revised the state soil erosion and sedimentation control regulations (Part 91). Anyone who knowingly violate Part 91 after receiving a letter of noncompliance are now responsible for fines from MDEQ of up to $25,000/day of violation plus the costs of restoration.
- Expected increases in public awareness over the next few years will leave many permit violators liable for third party law suits.
Keeping Your Site in Compliance
A comprehensive and integrated approach is required for protection of our natural resources during construction. The following techniques will improve the implementation of your SESC plan.
Portions of the site near sensitive and critical areas should never be disturbed. Limits of disturbance are marked on the SESC plan and should be clearly visible in the field. Ideally, only the areas actually needed to build structures and provide access should be cleared. Known as site fingerprinting, this technique can greatly reduce earthwork and SESC practice costs.
Streams and lakes are particularly susceptible to sedimentation. No clearing is permitted adjacent to a watercourse. As a secondary form of protection, perimeter controls, such as silt fence, should be installed along the perimeter of the watercourse buffer. If work is planned across or within the watercourse, special crossings and diversion techniques are required.
Carefully consider future and existing drainageways. Not only are drainageways the major route of sediment to lakes and streams, they are prone to severe erosion due to concentrated runoff. Consequently, special erosion controls such as check dams, vegetation, erosion control blankets, and turf reinforcement mats are applied to the drainageway depending on their slope and length and the size of the disturbed areas that drain to them.
Construction phasing (or staging) is similar to "just-in-time manufacturing" in that earthmoving occurs only when it is absolutely needed. Construction scheduling (sequencing) outlines the specific order of construction that the contractor must follow to complete a single phase. Expose the smallest practical area for the shortest time by properly scheduling and staging project activities. Disturb only first phase areas and stabilize before beginning subsequent phases. Plan phases so that earthwork is balanced within a phase.
Rapid Soil Stabilization
Maintain appropriate soil erosion controls as the primary practice. A grass or mulch cover should be established within two weeks after soil exposure. Mulch is particularly needed in winter months. By preventing erosion on site, the need for costly sediment control, imported topsoil, and restoration is reduced. Part 91 requires that permanent stabilization of disturbed areas must be completed within 5 days of final grading.
Protect Steep Slopes
Steep slopes are the most highly erodible surfaces of a construction site. Clearing and grading of existing steep slopes should be avoided. The use of silt fence at the toe of steep slopes should be carefully selected because flow velocities and sediment can quickly overload a silt fence. Additional practices may be required such as slope drains, scarification, erosion control blankets, and increased mulch and tackifier application rates.
Maintain sediment control practices to prevent soils from leaving the site. Common options are properly installed silt fence, compost berms, hydroseeded dikes, and diversions.
Think of erosion and sediment control practices as an insurance policy prior to storm events.
Employ Advanced Settling Devices
Even with the best SESC practices installed, construction sites can discharge high concentrations of sediment. The SESC plan for critical sites or sites larger than one acre should require some type of sediment trap or basin design to operate at (min.) 80% efficiency.
Adjust SESC Plan for Field Conditions
Even an effective plan may need to be modified during various phases due to discrepancies between planned and as-built grades, altered drainage, and unforeseen problems. The effectiveness of controls should be assessed daily. Maintenance repairs and additional or specialized controls may be required.
Assess Practices After Storms
After the passing of a runoff causing storm event, many SESC practices will likely require maintenance. The existing controls may need maintenance, clean out, reinforcement, or additional controls. Rapid response before the next storm is critical.
Site Specific Planning
Plan the development to fit the site topography, soils, drainage, and natural vegetation. When grading and Best Management Practices are designed to match a particular site, erosion is minimized, resulting in reduced costs.
Pre-construction meetings for sites larger than one acre or near sensitive areas help to define responsibilities, timelines, and appropriate contact information.
MDOT Storm Water Management Website