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{{alert|This page is an edit and testing page use by the wiki authors.  It is not a content page for the Manual. Information on this page may not be accurate and should not be used as guidance in managing stormwater.|alert-danger}}
 
{{alert|This page is an edit and testing page use by the wiki authors.  It is not a content page for the Manual. Information on this page may not be accurate and should not be used as guidance in managing stormwater.|alert-danger}}
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Materials for October 8, 2019 meeting on iron-enhanced treatments.
 +
*[[File:2019 iron enhanced meeting.docx]]
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*[[File:IESF Database FINAL.xlsx]]
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*[[File:23 37th Greenway Fe Enhanced Filter2016.docx]] - from the [https://www.minneapolisparks.org/_asset/0h9x3m/2016-Water-Resources-Report-for-printing.pdf Minneapolis Park & Recreation Board WATER RESOURCES REPORT 2016]
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[[Stormwater videos test page]]
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<!--
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Total Maximum Daily Loads (TMDLs) are EPA approved amounts of pollutant loading that can occur and have a water body meet water quality standards.  This page provides information on meeting MS4 permit requirements, general TMDL guidance, and links to other information related to TMDLs.
 +
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[[file:Riverconfluence.jpg|300 px|right|alt=image of Miss  and St Croix rivers confluence]]
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==TMDL guidance==
 +
*[[Summary of TMDL requirements in stormwater permits]]
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*[[Forms, guidance, and resources for completing the TMDL annual report form]]
 +
*Chloride
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*Bacteria
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*Dissolved oxygen, oxygen demand, temperature, and nitrogen
 +
 +
===TMDL toolkit for MS4 permit compliance===
 +
*[[Overview of models used to meet MS4 TMDL permit requirements]]
 +
*[[Recommendations and guidance for utilizing P8 to meet TMDL permit requirements]]
 +
**[[Case study for using P8 to meet TMDL permit requirements]]
 +
*[[Recommendations and guidance for utilizing WINSLAMM to meet TMDL permit requirements]]
 +
**[[Case study for using WINSLAMM to meet TMDL permit requirements]]
 +
*[[Recommendations and guidance for utilizing the MIDS calculator to meet TMDL permit requirements]]
 +
**[[MIDS calculator]]
 +
**[[Case study for using the MIDS calculator to meet TMDL permit requirements]]
 +
*[[Recommendations and guidance for utilizing the MPCA Simple Estimator to meet TMDL permit requirements]]
 +
**[[MPCA Simple Estimator]]
 +
**[[Case study for using the MPCA Simple Estimator to meet TMDL permit requirements]]
 +
*[[Recommendations and guidance for utilizing monitoring to meet TMDL permit requirements]]
 +
*[[Case studies for monitoring to meet TMDL permit requirements]]
 +
 +
==TMDL guidance and general information==
 +
*[[Overview of TMDLs]]
 +
*[http://www.pca.state.mn.us/index.php/view-document.html?gid=19465 Addressing TMDL Requirements in MS4 General Permit Applications and Stormwater Pollution Prevention Program Documents]
 +
*[http://www.pca.state.mn.us/index.php/view-document.html?gid=19456 List of approved TMDLs with MS4 Wasteload Allocations]
 +
*[[MPCA guidance for setting wasteload allocations for regulated stormwater]]
 +
*[[Technical guidance used by MPCA to develop guidelines for setting TMDL WLAs for regulated stormwater]]
 +
*[[Case studies for regulated stormwater issues]]
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*[[Guidance on what discharges should be included in the TMDL wasteload allocation for MS4 stormwater]]
 +
*[[Fact sheet on what discharges should be included in the TMDL wasteload allocation for MS4 stormwater]]
 +
*[[Guidance for addressing large watershed TMDL studies]]
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*[[Guidance for developing TMDL implementation plans for MS4 stormwater]]
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*[[Fact sheet for developing TMDL implementation plans for permitted MS4 stormwater]]
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*[[File:Guidance on What Discharges Should be Included in the TMDL Wasteload Allocation for MS4 Stormwater.docx|Guidance on What Discharges Should be Included in the TMDL Wasteload Allocation for MS4 Stormwater]] - August 2010
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*[[Construction activity by county]]
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 +
==Information received from MS4 permittees==
 +
*[[Summary of data received from permittees on MS4 TMDL permit reporting forms]]
 +
 +
==Links and other resources==
 +
*[[Links for TMDLs]] - '''we should get rid of this page'''
 +
*Visit the [https://www.pca.state.mn.us/water/total-maximum-daily-load-tmdl-projects#draft-pending-projects-990aee4d MPCA TMDL Project page] for information on specific projects across the state
 +
*[[Total Suspended Solids (TSS) in stormwater|Total Suspended Solids (TSS)]]
 +
*[[Phosphorus]]
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*[[Bacteria in stormwater]]
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*[[Chloride in stormwater]]
 +
*[https://stormwater.pca.state.mn.us/index.php?title=Protection_and_restoration_of_receiving_waters Protection and restoration of receiving waters]
 +
 +
[[Event mean concentrations for stormwater runoff]]
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-->
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<!--
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Proposing a portal called '''Compost'''. A portal is a page in the manual that provides links to multiple pages. The possible pages are indicated in the bulleted list below.
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<font size=4>'''Compost'''</font size>
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 +
*Overview of compost
 +
*Characteristics and material specifications for compost
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*Use of compost in stormwater best management practices (stormwater control measures)
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*Use of compost for erosion control
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*Use of compost for turf management, including alleviating soil compaction
 +
*Links
 +
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[[Hover box definitions]]
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-->
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<!--
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Chloride paper
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[[File:Chloride water problem.pptx]]
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[[File:March Water Issues talk.pptx]]
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[[File:March Water Issues talk.pptx]]
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[[File:March Water Issues talk.pptx]]
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-->
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<!--
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<img src="[https://stormwater.pca.state.mn.us/index.php?title=File:Screen_shot_of_calculator.png]" alt="calculator image"></img>
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<font size=5>'''This page could be dedicated to the image on setback distances'''</font size>
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<imagemap>
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Image:Test for image mapping.png|500px|thumb|alt=test image|Image map example.
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poly 200 0 200 100 150 100 100 0 [https://stormwater.pca.state.mn.us/index.php?title=Pretreatment Pretreatment]
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rect 0 0 50 50 [https://stormwater.pca.state.mn.us/index.php?title=Stormwater_pollutants stormwater pollutants]
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circle 100 140 40 [[Stormwater infiltration|infiltration page]]
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</imagemap>
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==Temporary mound==
 +
The localized groundwater surface may temporarily rise below an infiltration Best Management Practice (BMP), creating a condition termed groundwater mounding. Mounding can occur in areas where infiltrating water intersects a groundwater table and the rate of water entering the subsurface is greater than the rate at which water is conveyed away from the infiltration system (Susilo, 2009). Infiltration BMPs in particular have the potential to cause a groundwater mound, given the right subsurface conditions, because they direct the recharge to a specific area (Machusick and Traver, 2009). For more detail, [https://stormwater.pca.state.mn.us/index.php?title=Stormwater_infiltration_and_groundwater_mounding link here].
 +
 +
==Drinking water well==
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 +
==Septic system==
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==Building or structure==
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 +
[[test page 6|link to test page 6]]
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 +
[[Test Page 10|Cha's Test Page]]
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-->
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<!--
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[[File:Center pond.jpg|thumb|300px|alt=photo of a wet pond|<font size=3>Photo of a wet pond.</font size>]]
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 +
'''Description''':  A surface pond with a permanent pool that enables solids to settle during quiescent times. Water remains in the pond for treatment after the end of a storm event. Also known as a retention pond.
 +
 +
==Pollutants of Concern:==
 +
☒ Total Metals<br>
 +
☒ Dissolved Metals - Cd, Cr, Cu, Zn<br>
 +
☒ Total Phosphorus<br>
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☒ Oil/Grease<br>
 +
☒ Bacteria<br>
 +
☒ Organics (PCB/PAH)<br>
 +
☒ Oil and Grease<br>
 +
☒ Total Petroleum Hydrocarbons<br>
 +
☒ Trash
 +
 +
Data Available in [http://www.bmpdatabase.org/ International Stormwater Database]:  ☒  Yes    ☐  No
 +
 +
==Component Specific Considerations==
 +
*Space restrictions – 1 to 3 percent of contributing drainage area
 +
*Aviation concerns -- Depending on proximity to airports, vegetation must not be allowed to develop at the BMP that attracts wildlife that pose a hazard to aviation.
 +
*Soil type – low infiltration rate or lined with low permeability material
 +
*Vegetation – wetland plants (in permanent pool) and plants tolerant of wet and dry cycles (on embankment)
 +
*Topography – slopes adjacent to ponds should promote flow toward the wet pond
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*Temperature issues - increase overall heat inputs compared to untreated surface runoff, but reduce peak heat loading rates
 +
*Long dry periods – permanent pool must be maintained
 +
**If the stormwater BMP is close to an airport operations area, standing water should drain within 48 hours.
 +
*Pollutant concentration concerns – limited removal of dissolved pollutants; may export dissolved pollutants if not properly maintained
 +
*Construction costs – low to moderate
 +
*Maintenance costs - moderate
 +
*Mosquitoes – if water does not drain properly, wet ponds can become mosquito breeding grounds
 +
*Groundwater – in accordance with local requirements, maintain separation from groundwater used for drinking supply
 +
 +
==Design Criteria==
 +
Design criteria vary widely depending on site conditions, geographic locations, and local or state requirements. When designing constructed ponds, ensure the design is consistent with local or state requirements. Below is a list of general design considerations.
 +
*Ensure underlying soils are adequate and the constructed pond is properly sized to maintain a permanent pool. If underlying soils have high infiltration rates, a liner may be required.
 +
*Generally, intercepting the groundwater table will help maintain a permanent pool, but a liner is required if the underlying aquifer is sensitive to contamination
 +
*Maintain appropriate minimum horizontal distances between a water-supply well and the ordinary high water level of a storm water retention pond
 +
*Constructed ponds are not recommended in karst areas
 +
*If constructed ponds discharge to cold water fisheries, design for shorter detention times or a smaller permanent pool
 +
*The drainage area contributing to a constructed pond should be sufficient to maintain a permanent pool in the pond
 +
*Ensure forebays are properly located and sized
 +
*Pretreatment is recommended to reduce sediment loads to the constructed pond
 +
*Ensure inflow points, outflow points, and conveyance system are properly located, stabilized and protected, and have appropriate slopes. Conveyance system should include a non-clogging low flow orifice, emergency spillway, and pond drain.
 +
*Ensure outlets are protected from erosive discharges
 +
*Constructed ponds designed for treatment of specific pollutants may require specific features. For example, a shallow permanent pool prevents stratification and reduces the potential release of phosphorus from sediments.
 +
*Constructed ponds must have proper grading and site layout, considering factors such as pond side slopes, permanent pool slopes, length to width ratio, area of littoral zone, size and shape of pond benches, and shape and length of flow paths.
 +
*Ensure adequate maintenance access and incorporate safety features into design
 +
*Develop a landscaping plan for establishment of vegetation
 +
 +
Links to design information, representing different regions in the U.S., are included below.
 +
*[https://www.casqa.org/sites/default/files/BMPHandbooks/TC-20.pdf California Stormwater Quality Association. New Development and Redevelopment BMP Handbook. Section 5.7. TC-20 Wet Ponds]
 +
*[http://documents.atlantaregional.com/gastormwater/GSMM_2016%20EDITION_FINAL_V2.pdf Georgia Stormwater Manual. Volume 2 – Technical Handbook (See section 4.25)]
 +
*[http://www.maine.gov/dep/land/stormwater/stormwaterbmps/vol3/chapter4.pdf Maine Stormwater Best Practices Manual. Chapter 4. Wet Ponds]
 +
*[https://stormwater.pca.state.mn.us/index.php?title=Design_criteria_for_stormwater_ponds Minnesota Pollution Control Agency – Design criteria for stormwater ponds]
 +
*[http://www2.erie.gov/clarence/sites/www2.erie.gov.clarence/files/uploads/Stormwater%20Pond%20Training%20and%20Inspection%20Checklists.pdf New York State Stormwater Management Design Manual]
 +
*[https://ncdenr.s3.amazonaws.com/s3fs-public/Energy%20Mineral%20and%20Land%20Resources/Stormwater/BMP%20Manual/C-3%20%20Wet%20Pond%2004-17-17.pdf North Carolina Department of Environmental Quality Stormwater BMP Manual. C-3. Wet Pond]
 +
*[http://chesapeakestormwater.net/2012/03/design-specification-no-14-wet-pond/ Virginia Department of Conservation and Recreation Stormwater Design Specification No 14: Wet Pond]
 +
*[http://www.ecy.wa.gov/programs/wq/stormwater/manual/2014SWMMWWinteractive/2014%20SWMMWW.htm#Topics/VolumeV2014/VolV%20Ch10%202014/VolV%20BMPt1010%202014.htm%3FTocPath%3D2014%2520SWMMWW|Volume%2520V%2520-%2520Runoff%2520Treatment%2520BMPs|Chapter%2520V-10%2520-%2520Wetpool%2520Facilities|_____4 2014 Stormwater Management Manual for Western Washington. BMP T10.10: Wetponds – Basic and Large]
 +
 +
==Certifications==
 +
Washington State TAPE,  ☐TSS  ☐  Enhanced (Dissolved Metals) 
 +
☐Total Phosphorus  ☐  Oil/Grease
 +
 +
New Jersey CAT    ☐  TSS
 +
 +
Other: ☐    ______________________________________________
 +
*Hyperlinks to Certification Documents
 +
 +
==Construction Information==
 +
===Sequence===
 +
*Pre-construction meeting
 +
*Stabilize the drainage area
 +
*Assemble construction materials on-site and ensure they meet design specifications
 +
*Clear and strip the project area to the desired sub-grade
 +
*Install erosion and sediment controls
 +
*Excavate the core trench and install the spillway pipe
 +
*Install the riser or outflow structure
 +
*Construct the embankment and internal berms
 +
*Construct the impoundment area
 +
*Construct the emergency spillway
 +
*Install outlet pipes
 +
*Stabilize exposed soils
 +
*Plant the pond buffer area
 +
*References
 +
 +
===Considerations===
 +
*Sediment that has accumulated in the pond during construction must be removed after construction or may be used as pond liner material
 +
*Conduct inspections prior to construction, during initial site preparation, during excavation and grading, during installation of major features, at the time of vegetation establishment, and at the end of the project
 +
*Example inspection checklists
 +
**D.C. Department of Energy and Environment (See Appendix L)
 +
**Minnesota
 +
**New York State Stormwater Management Design Manual
 +
**Tennessee (Section 5)
 +
 +
==Operation and Maintenance Information==
 +
===Monitoring===
 +
*Inspect the condition of stormwater inlets to the pond for material damage, erosion or undercutting
 +
*Ensure the low flow orifice is not blocked or clogged
 +
*Inspect the condition of the principal spillway and riser for evidence of spalling, joint failure, leakage, corrosion, etc.
 +
*Inspect the pond outfall channel for erosion, undercutting, rip-rap displacement, woody growth, etc.
 +
*Inspect the condition of all trash racks, reverse-sloped pipes, or flashboard risers for evidence of clogging, leakage, debris accumulation, etc.
 +
*Inspect for animal burrows, sinkholes, wet areas, etc. along the fill embankments
 +
*Inspect for gullies, evidence of erosion, slumping, and other disturbances on the bank
 +
*Inspect internal and external side slopes of the pond for evidence of sparse vegetative cover
 +
*Inspect the banks of upstream and downstream channels for evidence of sloughing, animal burrows, boggy areas, woody growth, or gully erosion that may undermine embankment integrity
 +
*Monitor the growth of wetland plants, trees and shrubs planted. Record the species and their approximate coverage, and note the presence of any weeds, noxious plants, or invasive plant species.
 +
*Determine if vegetation needs maintenance (e.g. mowing, weeding)
 +
*Inspect vegetation to maintain efficacy of mosquito fish (if applicable)
 +
*Measure sediment accumulation levels, particularly in the forebay. In areas where road sand is used, an inspection of the forebay and permanent pool should be scheduled after the spring melt to determine if clean-out is necessary.
 +
*Inspect water levels to ensure a permanent pool of water is maintained
 +
*Inspect annually during winter freeze periods to look for signs of improper operation
 +
*Inspect maintenance access to ensure it is free of woody vegetation, and check to see whether valves, manholes and locks can be opened and operated
 +
*Determine if there is evidence of illicit discharges to the pond
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*Inspect the water to determine if there is a surface sheen (oil or gasoline), the color is murky (suspended sediment), green color (algae or other biological activity), or if there is an odor (gasoline or oil)
 +
**Inspect pretreatment practices to ensure they are functioning properly
 +
 +
===Maintenance===
 +
'''First or second year activities'''
 +
*Water vegetation as needed, particularly trees
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*Remove and replace any dead or dying plantings
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*Pond buffer and aquatic bench reinforcement plantings should occur in the second year after construction
 +
 +
'''Monthly to quarterly, after major storms, or as needed'''
 +
*Remove sediment from the low flow orifice and the pond inlets and outlets
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*Remove trash from trash rack
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*Keep vegetation at heights that allow inspection for animal burrows, sinkholes, wet areas, etc. along the fill embankments. Common mistakes are not mowing important areas because they are too steep or ignoring mowing completely. The amount of maintenance depends on the type of vegetation surrounding the basin. Some grasses need weekly mowing, and others can be maintained a couple of times a year.
 +
*Repair undercut, eroded, bare soil areas, and gullies in the bank
 +
*Maintain aquatic vegetation to maintain efficacy of mosquito fish (if applicable)
 +
 +
'''Semi-annually to annually, or as needed'''
 +
*Conduct shoreline cleanup to remove trash, debris and floatables
 +
*Open up the riser to access and test the valves
 +
*Repair broken mechanical components, if needed
 +
 +
===Non-routine maintenance===
 +
*Sediment removal in the forebay should occur every 5 to 7 years or after 50 percent of total forebay capacity has been lost. Sediment removal in the primary pool should occur approximately every 25 years or after 50 percent of the pool capacity has been reached. Sediments excavated from stormwater ponds that do not receive runoff from designated hotspots are not considered toxic or hazardous material and can be safely disposed by either land application or land filling. Sediment testing may be required prior to sediment disposal when a hotspot land use is present. Sediment removed from stormwater ponds should be disposed of according to an approved erosion and sediment control plan.
 +
*BMP components should be replaced if showing signs of wear, which typically occurs at times ranging from 5 to 25 years. Components may include
 +
**inflow and outflow devices;
 +
**trash racks and anti-vortex devices;
 +
**valves, orifices, and aerators;
 +
**concrete structures;
 +
**pumps and switches; and
 +
**earthworks such as embankments and side slopes.
 +
*Repair of structural components is required immediately if they impair the functionality of the pond.
 +
*Mowing of the pond buffer not located along maintenance rights-of-way and the embankment can be managed as a meadow (mowing every other year), prairie, or forest.
 +
*Ponds may be drained in an attempt to improve their functionality or conduct repairs. Ponds should not be drained during the spring, as temperature stratification and high chloride concentrations at the bottom can occur, which could result in negative downstream effects. Care should be exercised while draining the pond to prevent rapid release and minimize the discharge of sediments or anoxic water. The approving jurisdiction should be notified before draining a pond.
 +
 +
===Example inspection checklists===
 +
*[http://www.deq.virginia.gov/fileshare/wps/2013_SWM_Handbook/Chapter%2009/ Virginia DEQ]
 +
*[http://richmond.ky.us/images/planning/files/Stormwater_Pond_Checklist.pdf Richmond, Kentucky]
 +
*Oregon State University Extension
 +
*Metropolitan Nashville
 +
*Tinkers Creek
 +
*Center for Watershed Protection (see Appendix B)
 +
*Alliance of Rogue Communities
 +
*The Ohio State University (see Appendix B-2)
 +
*Clemson University (see Appendix D)
 +
*SanFrancisco
 +
*University of Minnesota
 +
 +
==References==
 +
*[https://www.casqa.org/sites/default/files/BMPHandbooks/tc-20_municipal_handbook_2003.pdf California Stormwater BMP Handbook]
 +
*[https://stormwater.pca.state.mn.us/index.php?title=Operation_and_maintenance_of_stormwater_ponds Minnesota Stormwater Manual]
 +
*Virginia DCR Stormwater Design Specification No. 14
 +
*Pennsylvania Stormwater Best Management Practices Manual
 +
*Washington Department of Ecology – 2014 Stormwater Management Manual for Western Washington
 +
*North Carolina DEQ Stormwater Design Manual
 +
 +
<noinclude>
 +
 +
==Related pages==
 +
*[https://stormwater.pca.state.mn.us/index.php?title=Stormwater_ponds Stormwater ponds] - main page
 +
*[[Overview for stormwater ponds]]
 +
*[[Types of stormwater ponds]]
 +
*[[Design criteria for stormwater ponds]]
 +
*[[Construction specifications for stormwater ponds]]
 +
*[[Assessing the performance of stormwater ponds]]
 +
*[[Operation and maintenance of stormwater ponds]]
 +
*[[Cost-benefit considerations for stormwater ponds]]
 +
*[[Calculating credits for stormwater ponds]]
 +
*[[References for stormwater ponds]]
 +
*[[Requirements, recommendations and information for using stormwater pond as a BMP in the MIDS calculator]]
 +
</noinclude>
 +
-->
 +
 +
 +
<!--
 
[[MN Stormwater comment page]]
 
[[MN Stormwater comment page]]
  
==Erosion Prevention And Sediment Control: INSPECTOR’S COMPLIANCE GUIDE (under Minnesota’s General Storm Water Permit for Construction Activity)==
+
=Erosion Prevention And Sediment Control: INSPECTOR’S COMPLIANCE GUIDE (under Minnesota’s General Storm Water Permit for Construction Activity)=
  
'''When doing inspections:'''
+
This page provides guidance for inspectors at construction stormwater sites covered under the [https://stormwater.pca.state.mn.us/index.php/Construction_stormwater_permit Construction Stormwater General Permit].
 +
 
 +
==Summary of actions to complete when doing inspections==
 
#Document time and date of the inspection, weather conditions and on-site contact persons.
 
#Document time and date of the inspection, weather conditions and on-site contact persons.
 
#Report any potential violations to the general contractor and representative of the owner.
 
#Report any potential violations to the general contractor and representative of the owner.
 
#Document all potential problems in field notes and photographs.
 
#Document all potential problems in field notes and photographs.
  
===RECORDS===
+
==Records==
 +
 
 +
===Record retention===
 +
The [https://stormwater.pca.state.mn.us/index.php?title=III._STORMWATER_DISCHARGE_DESIGN_REQUIREMENTS#III.A._STORMWATER_POLLUTION_PREVENTION_PLAN_CONTENT SWPPP] (original or copies) including, all changes to it, and inspections and maintenance records must be kept at the site during construction by the Permittee(s) who has/have operational control of that portion of the site. The SWPPP can be kept in either the field office or in an on‐site vehicle during normal working hours.
 +
 
 +
All owner(s) must keep the following records on file for three (3) years after submittal of the Notice of Termination (NOT) as outlined in [https://stormwater.pca.state.mn.us/index.php?title=II._SUBMITTING_THE_APPLICATION#II.C._TERMINATION_OF_COVERAGE_COVERAGE Part II.C]. This does not include any records after submittal of the NOT.
 +
#The final SWPPP
 +
#Any other stormwater related permits required for the project
 +
#Records of all inspection and maintenance conducted during construction (Part IV.E. Inspections and Maintenance)
 +
#All permanent operation and maintenance agreements that have been implemented, including all right‐of‐way, contracts, covenants and other binding requirements regarding perpetual maintenance and
 +
#All required calculations for design of the temporary and permanent Stormwater Management Systems.
 +
 
 +
===Record availability [https://stormwater.pca.state.mn.us/index.php?title=V._GENERAL_PROVISIONS#V.B._RECORD_AVAILABILITY (Part V.B. of the permit)]===
 +
#The Permittee(s) must make the SWPPP, including all certificates, reports, records, or other information required by this permit, available to federal, state, and local officials within 72 hours upon request for the duration of the permit and for three (3) years following the NOT. This does not include any records after submittal of the NOT.
 +
#When requested by the MPCA, the Permittee(s) must make the responsible person trained as required in [[III. STORMWATER DISCHARGE DESIGN REQUIREMENTS#III.F. TRAINING REQUIREMENTS|Part III.F.1.b. or Part III.F.1.c]]. available to be onsite during an MPCA inspection within 72 hours of a request.
 +
 
  
The project’s final plans and specifications, which include both temporary and permanent control plan requirements, must be available at the construction site in either a field office or an
+
''The project’s final plans and specifications, which include both temporary and permanent control plan requirements, must be available at the construction site in either a field office or an
 
inspector’s or contractor’s vehicle.
 
inspector’s or contractor’s vehicle.
  
Line 25: Line 354:
 
*documentation of all changes to the Temporary Erosion and Sediment Control Plan made during construction.
 
*documentation of all changes to the Temporary Erosion and Sediment Control Plan made during construction.
  
If the records requirements are not being complied with, it may be a violation of permit provisions (see permit provisions parts I.C.1, I.C.2.a, I.C.2.b, I.C.2.c).
+
If the records requirements are not being complied with, it may be a violation of permit provisions (see permit provisions parts I.C.1, I.C.2.a, I.C.2.b, I.C.2.c).''
  
 
===Permit Coverage Card===
 
===Permit Coverage Card===
 
 
A notice of stormwater permit coverage card must be placed in a visible location at the construction site throughout the duration of the project. The card can be placed at any of the following locations:
 
A notice of stormwater permit coverage card must be placed in a visible location at the construction site throughout the duration of the project. The card can be placed at any of the following locations:
 
*construction site entrance, visible from the nearest public roadway;
 
*construction site entrance, visible from the nearest public roadway;
 
*where no construction site entrance exists, at a location visible from the nearest public roadway;
 
*where no construction site entrance exists, at a location visible from the nearest public roadway;
 
*at the field office (if applicable); or
 
*at the field office (if applicable); or
for linear utility and noncontiguous municipal projects (i.e., city street improvements), at the office responsible for the project’s administration.
+
*for linear utility and noncontiguous municipal projects (i.e., city street improvements), at the office responsible for the project’s administration.
  
 
If the records requirements are not being complied with, it is a violation of permit provisions (see permit provisions parts I.C.2.d, I.C.3).
 
If the records requirements are not being complied with, it is a violation of permit provisions (see permit provisions parts I.C.2.d, I.C.3).
  
===EROSION AND SEDIMENT CONTROL DURING CONSTRUCTION===
+
==Erosion and sediment control during construction==
 
 
 
'''Erosion Control.''' Permittee must use horizontal slope grading, construction phasing, temporary diversions, and/or other practices that minimize erosion.
 
'''Erosion Control.''' Permittee must use horizontal slope grading, construction phasing, temporary diversions, and/or other practices that minimize erosion.
  
Line 55: Line 382:
 
If the ditch and outlet stabilization is not being complied with, it is a violation of permit provisions (see permit provisions parts I.D.1.c, I.D.1.d).
 
If the ditch and outlet stabilization is not being complied with, it is a violation of permit provisions (see permit provisions parts I.D.1.c, I.D.1.d).
  
===PERIMETER CONTROLS.===
+
==Perimeter controls==
 
 
 
'''All down gradient perimeter sediment-control bmps must be in place before any up gradient land-disturbing activity begins.'''
 
'''All down gradient perimeter sediment-control bmps must be in place before any up gradient land-disturbing activity begins.'''
  
Line 69: Line 395:
 
If permanent ponds are required, they can often be used in place of temporary ponds, but construction sediment should be removed before final Notice of Termination has been submitted.
 
If permanent ponds are required, they can often be used in place of temporary ponds, but construction sediment should be removed before final Notice of Termination has been submitted.
  
===BMP INSPECTION===
+
==BMP inspection==
 
 
 
Inspect all erosion- and perimeter-sediment-control BMPs to ensure integrity and effectiveness.  All nonfunctional perimeter-sediment-control BMPs should be repaired when the trapped sediment reaches one-third of the height, or replaced or supplemented with functional BMPs within 24 hours of discovery. All nonfunctional erosion-control BMPs should be repaired or replaced within 24 hours of discovery, or as soon as field conditions allow access.
 
Inspect all erosion- and perimeter-sediment-control BMPs to ensure integrity and effectiveness.  All nonfunctional perimeter-sediment-control BMPs should be repaired when the trapped sediment reaches one-third of the height, or replaced or supplemented with functional BMPs within 24 hours of discovery. All nonfunctional erosion-control BMPs should be repaired or replaced within 24 hours of discovery, or as soon as field conditions allow access.
  
Line 77: Line 402:
 
If inspection and maintenance is not being complied with, it is a violation of permit provisions (see permit provisions parts I.E.1.a, I.E.1.b).
 
If inspection and maintenance is not being complied with, it is a violation of permit provisions (see permit provisions parts I.E.1.a, I.E.1.b).
  
===SEDIMENT LEAVING THE SITE===
+
==Sediment leaving the site==
 
 
 
Inspect all drainage ditches and other waters of the state for evidence of sediment leaving the site. Unless the project has received approval or certification for depositing fill into waters of the state, the permittee should remove all sediment in drainageways, catch basins or other waters of the state and restabilize the areas where sediment removal results in exposed soil. The removal and stabilization must take place within seven days of discovery unless precluded by legal, regulatory or physical access restraints. If precluded, removal and stabilization must take place within seven calendar days of obtaining access.
 
Inspect all drainage ditches and other waters of the state for evidence of sediment leaving the site. Unless the project has received approval or certification for depositing fill into waters of the state, the permittee should remove all sediment in drainageways, catch basins or other waters of the state and restabilize the areas where sediment removal results in exposed soil. The removal and stabilization must take place within seven days of discovery unless precluded by legal, regulatory or physical access restraints. If precluded, removal and stabilization must take place within seven calendar days of obtaining access.
  
Line 85: Line 409:
 
If sediment leaving the site is not being inspected and corrected, it is a violation of permit provisions (see permit provisions parts I.E.1.c, I.E.1.d).
 
If sediment leaving the site is not being inspected and corrected, it is a violation of permit provisions (see permit provisions parts I.E.1.c, I.E.1.d).
  
===VIOLATION FOLLOW-UP===
+
==Violation follow-up==
 
 
 
Alleged violations must be brought to the attention of the on-site general contractor and representative of the owner (if that person is present) before leaving the site.  
 
Alleged violations must be brought to the attention of the on-site general contractor and representative of the owner (if that person is present) before leaving the site.  
  
Line 97: Line 420:
 
Violations not remediated in accordance with the time frames specified in the permit are subject to MPCA enforcement action, pursuant to Minn. Stat. §§ 115.071, 116.072, and 609.671, for violation of water-quality environmental laws.
 
Violations not remediated in accordance with the time frames specified in the permit are subject to MPCA enforcement action, pursuant to Minn. Stat. §§ 115.071, 116.072, and 609.671, for violation of water-quality environmental laws.
  
===Sample Check List:===
+
==Sample checklist for resource management plan review (Scott County Soil and Water Conservation District)==
 
+
*General information to be included with or as part of the Resource Management Plan (RMP)
====CHECKLIST FOR RESOURCE MANAGEMENT PLAN REVIEW BY: SCOTT SOIL AND WATER CONSERVATION DISTRICT====
+
**Project Description – narrative describing the nature and extend of the land disturbing activity.
 
+
**Existing Site Conditions – describe existing topography, drainage patterns and wetlands.
General information to be included with or as part of the Resource Management Plan (RMP):
+
**Soils – show soil boundaries, include: mapping unit, soil name, slopes and hydrologic group.
*Project Description – narrative describing the nature and extend of the land disturbing activity.
+
**Location Map – show the site with respect to the surrounding areas.
*Existing Site Conditions – describe existing topography, drainage patterns and wetlands.
+
**Drawing Data – indicate north, show scale and include benchmark for horizontal and vertical datum.
*Soils – show soil boundaries, include: mapping unit, soil name, slopes and hydrologic group.
+
**Plan Preparer – name and phone number of individual responsible for plan preparation.
*Location Map – show the site with respect to the surrounding areas.
+
**Existing Contours – show existing 2 foot contours (at least 200 ft beyond property boundaries).
*Drawing Data – indicate north, show scale and include benchmark for horizontal and vertical datum.
+
**Final Contours – show proposed 2 ft contours for proposed grading.
*Plan Preparer – name and phone number of individual responsible for plan preparation.
+
**Existing Vegetation – show different cover conditions for the entire site with approximate areas.
*Existing Contours – show existing 2 foot contours (at least 200 ft beyond property boundaries).
+
**Property Boundaries – show property boundaries, lot lines, section lines and adjacent plats.
*Final Contours – show proposed 2 ft contours for proposed grading.
+
**Adjacent Areas – narrative describing which neighboring properties will be affected by proposed plat.
*Existing Vegetation – show different cover conditions for the entire site with approximate areas.
+
**Elevation and Grade – street and ditch grades, pond, wetland, lake NWL and HWL, pipe inverts.
*Property Boundaries – show property boundaries, lot lines, section lines and adjacent plats.
+
**Location of BMP’s – location of erosion and sediment control features (BMP Criteria).
*Adjacent Areas – narrative describing which neighboring properties will be affected by proposed plat.
+
**Location of Utilities – location of existing and proposed utilities if known.
*Elevation and Grade – street and ditch grades, pond, wetland, lake NWL and HWL, pipe inverts.
+
*Stormwater Management information to be included on or with the Resource Management Plan
*Location of BMP’s – location of erosion and sediment control features (BMP Criteria).
+
**Drainage Areas – show existing and proposed drainage areas used for stormwater analysis.
*Location of Utilities – location of existing and proposed utilities if known.
+
**Runoff Curve Numbers (RCN’s) – detailed breakdown of existing and proposed RCN’s used.
 
+
**Impervious Coverage – list assumptions for determining impervious area (house pad, driveway, etc. List new impervious area for each subwatershed (if 1 acre or more drains to a discernible point, a wet detention pond is needed for treatment of runoff prior to discharge to water of the state according to W.W. Walker criteria. If development does not require a pond based on these standards and the development will be creating over an acre of impervious, a wet detention pond is still needed).
====Stormwater Management information to be included on or with the Resource Management Plan====
+
**Drainage Calculations – show calculations for 2, 10 and 100 year peak discharge rates comparing existing and proposed conditions with comparable subwatersheds (TR 55 method or similar methodologies).
 
 
*Drainage Areas – show existing and proposed drainage areas used for stormwater analysis.
 
*Runoff Curve Numbers (RCN’s) – detailed breakdown of existing and proposed RCN’s used.
 
*Impervious Coverage – list assumptions for determining impervious area (house pad, driveway, etc.
 
 
 
List new impervious area for each subwatershed (if 1 acre or more drains to a discernible point, a wet detention pond is needed for treatment of runoff prior to discharge to water of the state according to W.W. Walker criteria. If development does not require a pond based on these standards and the development will be creating over an acre of impervious, a wet detention pond is still needed).
 
*Drainage Calculations – show calculations for 2, 10 and 100 year peak discharge rates comparing existing and proposed conditions with comparable subwatersheds (TR 55 method or similar methodologies).
 
 
*Precipitation Events – rainfall depths for the 2, 10 and 100 year 24-hour frequency storm events are 2.8, 4.2 and 6.0 inches respectively (reference US Weather Bureau Technical Paper 40). Stormwater ponding will be based on the 6.0 inch event. On site conveyance systems will be designed for the 4.2 inch event.
 
*Precipitation Events – rainfall depths for the 2, 10 and 100 year 24-hour frequency storm events are 2.8, 4.2 and 6.0 inches respectively (reference US Weather Bureau Technical Paper 40). Stormwater ponding will be based on the 6.0 inch event. On site conveyance systems will be designed for the 4.2 inch event.
*Detention Pond – calculations for pond used to control peak discharge rates (BMP Criteria)
+
**Detention Pond – calculations for pond used to control peak discharge rates (BMP Criteria)
*Wet Detention Pond – NURP pond used for nutrient removal and peak discharge rate control. Show calculations for estimated inflow and outflow, permanent and temporary storage volumes, mean depth, outlet design, downstream stabilization, emergency spillway, pond profile and pond cross section. (W.W. Walker criteria.)
+
**Wet Detention Pond – NURP pond used for nutrient removal and peak discharge rate control. Show calculations for estimated inflow and outflow, permanent and temporary storage volumes, mean depth, outlet design, downstream stabilization, emergency spillway, pond profile and pond cross section. (W.W. Walker criteria.)
*Floatable Skimmers – included on outlet of wet detention ponds. Show construction details on plan.
+
**Floatable Skimmers – included on outlet of wet detention ponds. Show construction details on plan.
*Volume Increase – increased RCN’s will increase the volume and duration of runoff leaving the site. These increases in volume and duration may have a negative effect on downstream conveyance.
+
**Volume Increase – increased RCN’s will increase the volume and duration of runoff leaving the site. These increases in volume and duration may have a negative effect on downstream conveyance.
*Ground Water Sensitivity – areas identified as being highly susceptible to ground water contamination need the following standards incorporated into the design of the wet detention pond: pond will be lined with 2 ft of impermeable soil.
+
**Ground Water Sensitivity – areas identified as being highly susceptible to ground water contamination need the following standards incorporated into the design of the wet detention pond: pond will be lined with 2 ft of impermeable soil.
*Flood Plain – show protected waters on the grading plan with associated predicted 100 year flood plain. Show calculations for 100 year flood plain predictions.
+
**Flood Plain – show protected waters on the grading plan with associated predicted 100 year flood plain. Show calculations for 100 year flood plain predictions.
*Any land locked areas need to be accounted for in the design analysis for existing conditions. If no outlet is present, what is the predicted 100 year flood elevation and how will this be maintained?
+
**Any land locked areas need to be accounted for in the design analysis for existing conditions. If no outlet is present, what is the predicted 100 year flood elevation and how will this be maintained?
*Show existing tile lines. Design should plan as though tiles will no longer function unless an easement is supplied for future maintenance.
+
**Show existing tile lines. Design should plan as though tiles will no longer function unless an easement is supplied for future maintenance.
 
+
*Erosion Control information to be included on or with the Resource Management Plan
====Erosion Control information to be included on or with the Resource Management Plan====
+
**Implementation Schedule – list the order of operations for construction activities. Include:
 
+
***Phasing of construction – start and completion dates for each phase.
*Implementation Schedule – list the order of operations for construction activities. Include:
+
***List order of operations – all erosion control measures shall be installed and must be functional prior to upslope grading activities taking place.
#Phasing of construction – start and completion dates for each phase.
+
***Contact Person – individual responsible maintaining the erosion and sediment control features.
#List order of operations – all erosion control measures shall be installed and must be functional prior to upslope grading activities taking place.
+
***Disposal or removal of erosion and sediment control features upon final stabilization of project.
#Contact Person – individual responsible maintaining the erosion and sediment control features.
+
***Pond clean out – removal of sediment from pond upon final stabilization to design elevations.
#Disposal or removal of erosion and sediment control features upon final stabilization of project.
+
**Critical Erosion Areas – describe areas with potential for serious erosion problems.
#Pond clean out – removal of sediment from pond upon final stabilization to design elevations.
 
*Critical Erosion Areas – describe areas with potential for serious erosion problems.
 
 
*Limits of Disturbed Area – if 5 acres or more drain to a discernible point, then a temporary sediment control basin is needed to treat runoff.
 
*Limits of Disturbed Area – if 5 acres or more drain to a discernible point, then a temporary sediment control basin is needed to treat runoff.
*Stabilization of exposed and soil stockpile areas.
+
**Stabilization of exposed and soil stockpile areas.
*Stabilizing of waterways and outlets – on site conveyance systems capable of handling the 5 year 24-hour frequency storm (3.6”) without erosion.
+
**Stabilizing of waterways and outlets – on site conveyance systems capable of handling the 5 year 24-hour frequency storm (3.6”) without erosion.
#Adjacent properties protected from erosion.
+
**Adjacent properties protected from erosion.
#Storm Sewer Inlets – protection provided to prevent sediment laiden water from entering (if applicable).
+
**Storm Sewer Inlets – protection provided to prevent sediment laiden water from entering (if applicable).
#Permanent Erosion Control – grass seed, fertilizer and mulching specifications and rates listed. Mulch anchoring methods and time requirements for permanent seeding listed. (15 days after substantial grading completed).
+
**Permanent Erosion Control – grass seed, fertilizer and mulching specifications and rates listed. Mulch anchoring methods and time requirements for permanent seeding listed. (15 days after substantial grading completed).
*Rip Rap – rip rap placed at all culvert outfalls to minimize scour.
+
**Rip Rap – rip rap placed at all culvert outfalls to minimize scour.
*Rock Construction Entrances – entrances planned where applicable to minimize tracking onto roads.
+
**Rock Construction Entrances – entrances planned where applicable to minimize tracking onto roads.
*BMP Construction Details – include on the erosion control plan all construction details for BMP’s used.
+
**BMP Construction Details – include on the erosion control plan all construction details for BMP’s used.
*Incorporate horizontal slope grading where applicable.  
+
**Incorporate horizontal slope grading where applicable.
 +
*Wetlands
 +
**Has wetland delineation been submitted to the LGU and the Scott Soil and Water Conservation District for review.
 +
**Have the wetlands been surveyed as part of the plat.
 +
**Show normal water levels and 100 year flood elevations for all wetlands.
 +
**Have wetland easements been identifed around all wetland areas delineated as wetland.
 +
**Have wetland regulations been complied with prior to approval of preliminary plat.
  
====Wetlands====
+
=Erosion Prevention and Sediment Control: PROVISIONS IN CONTRACTS=
*Has wetland delineation been submitted to the LGU and the Scott Soil and Water Conservation District for review.
 
*Have the wetlands been surveyed as part of the plat.
 
*Show normal water levels and 100 year flood elevations for all wetlands.
 
*Have wetland easements been identifed around all wetland areas delineated as wetland.
 
*Have wetland regulations been complied with prior to approval of preliminary plat.
 
 
 
==Erosion Prevention and Sediment Control: PROVISIONS IN CONTRACTS==
 
  
 
Once the planner has decided upon methods of pollution prevention and control, the plan must be implemented. Work that is being constructed under unit-priced contracts will require a clear and concise explanation of the requirements in contract documents.
 
Once the planner has decided upon methods of pollution prevention and control, the plan must be implemented. Work that is being constructed under unit-priced contracts will require a clear and concise explanation of the requirements in contract documents.
Line 254: Line 567:
  
  
 +
'''Key runoff-control measures''' should be located in conjunction with sediment traps to divert water from planned undisturbed areas out of the traps and sediment-laden water into the traps. Install diversions above areas to be disturbed prior to grading. Place necessary perimeter dikes with stable outlets before opening major areas for development. Install additional needed runoff control measures as grading takes place.
 +
 +
{{:Considerations for construction scheduling}}
 +
 +
'''The main runoff-conveyance system''' with inlet and outlet protection devices should be installed early, and used to convey stormwater runoff through the development site without creating gullies and washes. Install inlet protection for storm drains as soon as the drain is functional to trap sediment on site in shallow pools and to allow flood flows to safely enter the storm-drainage system. Install outlet protection at the same time as the conveyance system to prevent damage to
 +
the receiving stream.
 +
 +
Normally, install stream stabilization, including necessary stream crossings, independently and ahead of other construction activities. It is usually best to schedule this work as soon as weather conditions permit. Site clearing and project construction increases storm runoff, often making stream-bank-stabilization work more difficult and costly.
 +
 +
Begin grubbing and grading as soon as key erosion- and sediment-control measures are in place. Once a scheduled development area is cleared, grading should follow immediately so that protective ground cover can be re-established quickly. Do not leave any area bare and exposed for extended periods (see NPDES permit requirements). Leave adjoining areas planned for development or ones that are to be used for borrow and disposal undisturbed as long as possible
 +
to serve as natural buffer zones.
 +
 +
Runoff control is essential during the grading operation. Temporary diversions, slope drains, and inlet and outlet protection installed in a timely manner can be very effective in controlling erosion during this critical period of development.
  
 +
After the land is cleared and graded, apply surface stabilization on graded areas, channels, dikes and other disturbed areas. Stabilize any disturbed area where active construction will not take place for 21 working days (see NPDES permit requirements) by temporary seeding and/or mulching or by other suitable means. Install permanent stabilization measures after final grading, in accordance with the vegetative plan. Temporary seeding and/or mulching may be
 +
necessary during extreme weather conditions with permanent vegetation measures delayed until a more suitable installation time.
 +
 +
Coordinate building construction with other development activities so that all work can take place in an orderly manner and on schedule. Experience shows that careful project scheduling improves efficiency, reduces cost and lowers the potential for erosion and sedimentation problems.
 +
 +
Landscaping and final stabilization is the last major construction phase, but the topsoil stockpiling, tree preservation, undisturbed buffer area, and well-planned road locations established earlier in the project may determine the ease or difficulty of this activity. All disturbed areas should have permanent stabilization practices applied. Unstable sediment should be removed from sediment basins and traps and incorporated into the topsoil, not just spread on
 +
the surface. All temporary structures should be removed after the area above has been properly stabilized. Borrow and disposal areas should be permanently vegetated or otherwise stabilized.
 +
 +
In planning construction work, it may be helpful to outline all land-disturbing activities necessary to complete the proposed project. Then list all practices needed to control erosion and sedimentation on the site. These two lists can then be combined in logical order to provide a practical and effective construction-sequence schedule.
 +
 +
 +
====DESIGN CRITERIA====
 +
 +
At a minimum, the construction sequence schedule should show the following:
 +
*the erosion- and sedimentation-control practices to be installed,
 +
*principal development activities,
 +
*the measures that should be in place before other activities are begun, and
 +
*compatibility with the general construction schedule of the contract.
 +
 +
====CONSTRUCTION SPECIFICATIONS====
 +
 +
Many timely construction techniques, such as shaping earthen fills daily to prevent overflows and constructing temporary diversions ahead of anticipated storms, can reduce the erosion potential
 +
of a site. These type of activities cannot be put on the construction sequence but should be used whenever possible.
 +
 +
Following a planned construction-sequence schedule to control erosion should help keep field personnel aware of the possibilities of erosion prevention through construction management.
 +
 +
====MAINTENANCE====
 +
 +
Follow the construction sequence throughout project development. When changes in construction activities are needed, amend the sequence schedule in advance to maintain management control.
 +
 +
Orderly modification assures coordination of construction and erosion-control practices to minimize erosion and sedimentation problems. When major changes are necessary, you may want to send a copy of the modified schedule to the local permitting authority.
  
  
Line 314: Line 671:
 
*[[Determining soil infiltration rates]]
 
*[[Determining soil infiltration rates]]
 
*Cold climate considerations for infiltration practices - See [http://stormwater.pca.state.mn.us/index.php/Cold_climate_impact_on_runoff_management#Infiltration], [http://stormwater.pca.state.mn.us/index.php/Cold_climate_impact_on_runoff_management#Infiltration_practices]
 
*Cold climate considerations for infiltration practices - See [http://stormwater.pca.state.mn.us/index.php/Cold_climate_impact_on_runoff_management#Infiltration], [http://stormwater.pca.state.mn.us/index.php/Cold_climate_impact_on_runoff_management#Infiltration_practices]
 
+
-->
  
  

Latest revision as of 19:08, 8 October 2019

Warning: This page is an edit and testing page use by the wiki authors. It is not a content page for the Manual. Information on this page may not be accurate and should not be used as guidance in managing stormwater.


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