- MIDS design sequence flow chart - Box 1 - Did you gather site information?
- MIDS design sequence flow chart - Box 2 - Prior to using the flow chart, gather the following preliminary information.
- Conduct site review
- Define performance goal
- MIDS design sequence flow chart - Box 3 - Define Performance Goal
- New and redevelopement projects: Retain on site a volume of 1.1 inches from impervious surfaces
- Linear projects: Retain on site the larger of 1.1 inches from all new, or 0.55 inches from all new and fully reconstructed impervious surfaces
- MIDS design sequence flow chart - Box 4- Does the project create one acre or more of new and/or fully reconstructed impervious surfaces?
- MIDS design sequence flow chart - Box 5 - MIDS performance goal does not apply (The project creates less than one acre of new and/or fully reconstructed impervious surfaces)
- MIDS design sequence flow chart - Box 6 - Is the project linear?
- MIDS design sequence flow chart - Box 7 - Are there restraints due to lack of available right-of-way, off-site drainage and/or rate control requirements?
- MIDS design sequence flow chart - Box 8 - Is Flexible Treatment Option (FTO) 2 feasible?
- MIDS design sequence flow chart - Box 9 - Select Flexible Treatment Option (FTO) 2
- Provide documentation of offsite runon to project area
- Provide documentation of lack of right-of-way
- MIDS design sequence flow chart - Box 10 - Select FTO #3. Provide site survey, maps, regulations, and/or cost estimates documenting that meeting the original performance goal of FTO alternatives is not feasible in addition to other documentation as required by LGU.
- MIDS design sequence flow chart - Box 11 - Are there zoning and land use requirements that make the Performance Goal not feasible?
- MIDS design sequence flow chart - Box 12 - Is BMP relocation feasible?
- MIDS design sequence flow chart - Box 13 - Is Flexible Treatment Option (FTO) 1 feasible?
- MIDS design sequence flow chart - Box 14 - Is Flexible Treatment Option (FTO) 2 feasible?
- MIDS design sequence flow chart - Box 15 - Is the site located in a DWSMA, wellhead protection area or within 200 feet of a drinking water well?
- MIDS design sequence flow chart - Box 16 - Is infiltration in this location permitted by the LGU, owner and operator?
- MIDS design sequence flow chart - Box 17 - Are there existing or proposed structures or infrastructure that make the performance goal not feasible?
- MIDS design sequence flow chart - Box 18 - Is BMP relocation feasible?
- MIDS design sequence flow chart - Box 19 - Is Flexible Treatment Option (FTO) 1 feasible?
- MIDS design sequence flow chart - Box 20 - Is Flexible Treatment Option (FTO) 2 feasible?
- MIDS design sequence flow chart - Box 21 - Is karst present of the site?
- MIDS design sequence flow chart - Box 22 - Conduct detailed site investigation.
- MIDS design sequence flow chart - Box 23 - Is karst present within 1000 feet of proposed BMP location?
- MIDS design sequence flow chart - Box 24 - Is BMP relocation on-site to a location without karst feasible?
- MIDS design sequence flow chart - Box 25 - Select Flexible Treatment Option (FTO) 2
- No infiltration practices allowed
- Explore non-infiltration volume reduction practices
- Provide soil borings or report from a professional geologist or geotechnical engineer
- MIDS design sequence flow chart - Box 26 - Is shallow groundwater or shallow bedrock present on site?
- MIDS design sequence flow chart - Box 27 - Conduct detailed site investigation.
- MIDS design sequence flow chart - Box 28 - Is there more than 3 feet of soil depth (More than 10 feet is preferred) from bottom of the BMP to bedrock and/or groundwater?
- MIDS design sequence flow chart - Box 29 - Is BMP relocation onsite to avoid shallow groundwater and bedrock feasible?
- MIDS design sequence flow chart - Box 30 - Can the BMP be raised?
- MIDS design sequence flow chart - Box 31 - Select Flexible Treatment Option (FTO) 2
- No infiltration practices allowed
- Explore non-infiltration volume reduction practices
- Provide soil borings or report from a professional geologist or geotechnical engineer
- MIDS design sequence flow chart - Box 32 - Raise BMP enough to ensure 3 feet (preferably 10 feet) of soil between bottom of BMP and top of bedrock and groundwater
- MIDS design sequence flow chart - Box 33 - Is there presence of contaminated soils and/or groundwater, or hotspot runoff?
- MIDS design sequence flow chart - Box 34 - Can hotspot or contamination be isolated or remediated to mitigat risk of increased contamination?
- MIDS design sequence flow chart - Box 35 - Select Flexible Treatment Option (FTO) 2
- No infiltration practices allowed
- Explore non-infiltration volume reduction practices
- Provide Phase I or II ESAs or other documentation of potential contamination or hotspot runoff
- Provide documentation of extent of contamination and remediation alternatives considered
- MIDS design sequence flow chart - Box 36 - Are there very low infiltrating soils (<0.2 inches per hour) on site?
- MIDS design sequence flow chart - Box 37 - Is BMP relocation on site to a higher infiltrating location feasible?
- MIDS design sequence flow chart - Box 38 - Can the BMP be sized to drain dry within 48 hours (24 hours in locations that are tributary to trout streams)?
- MIDS design sequence flow chart - Box 39 - Provide soil boring or infiltration test results documenting low-infiltrating soils
- MIDS design sequence flow chart - Box 40 - Is Flexible Treatment Option (FTO) 1 (lower volume control standard) feasible, allowing the BMP to drain within 48 hours (24 hours in locations tributary to trout streams)?
- MIDS design sequence flow chart - Box 41 - Select Flexible Treatment Option (FTO) 2
- No infiltration practices allowed
- Explore non-infiltration volume reduction practices
- Provide soil boring or infiltration test results documenting low-infiltration soils
- MIDS design sequence flow chart - Box 42 - Are there very high infiltrating soils (more than 8 inches per hour)?
- MIDS design sequence flow chart - Box 43 - Is BMP relocation on site to a lower infiltrating location feasible?
- MIDS design sequence flow chart - Box 44 - Can subgrade be modified to slow the rate of infiltration to less than 8 inches per hour?
- MIDS design sequence flow chart - Box 45 - Select Flexible Treatment Option (FTO) 2.
- No infiltration practices allowed
- Explore non-infiltration volume reduction practices
- Provide soil boring or infiltration test results documenting high-infiltration soils
- MIDS design sequence flow chart - Box 46 - Are there adverse surface water hydrologic impacts from infiltration practices (e.g. impacting perched wetland)?
- MIDS design sequence flow chart - Box 47 - Can the BMP be relocated onsite to avoid adverse hydrologic impacts?
- MIDS design sequence flow chart - Box 48 - Would BMPs accomodating Flexible Treatment Option (FTO) 1 avoid adverse hydrologic impacts?
- MIDS design sequence flow chart - Box 49 - Select FTO Alternative No. 2
- Maximize infiltration BMPs to treat up to the 0.55 inch goal, if possible
- Explore non-infiltration volume reduction practices
- provide report documenting potential hydrologic impacts from infiltration on the site, prepared by a registered engineer, hydrologist, or wetland specialist
- MIDS design sequence flow chart - Box 50 - Select FTO Alternative No. 1
- Maximize infiltration BMPs to treat more than 0.55 inch goal if possible
- Provide report documenting potential hydrologic impacts from infiltration on the site, prepared by a registered engineer, hydrologist, or wetlands specialist.
- MIDS design sequence flow chart - Box 51 - Complete design using the following performance goals
- New development projects - 1.1 inches from new impervious surfaces
- Redevelopment projects - 1.1 inches from new impervious surfaces
- Linear projects
- 0.55 inches of runoff from the new and fully reconstructed impervious surfaces
- 1.1 inches of runoff from the net increase in impervious area
- MIDS design sequence flow chart - Box 52 - Do the following conditions apply?
- Zoning and land use requirements make FTO 2 not feasible; and
- The BMP cannot be relocated to accomodate zoning and land use restrictions
- MIDS design sequence flow chart - Box 53 - Do the following conditions apply?
- There are existing or proposed structures or infrastructure that make FTO 2 not feasible; and
- BMP relocation is not feasible
- MIDS design sequence flow chart - Box 54 Do any of the following conditions apply? (NOTE: If any condition applies, you do not need to answer the remaining questions.)
- The site is located within a DWSMA, wellhead protection area or within 200 feet of a drinking water well and infiltration is not allowed by the LGU
- Karst is present within 1000 feet of the site and the BMP cannot be reloacted so that it is more than 1000 feet from karst
- Shallow groundwater or shallow bedrock is present within 3 feet of the bottom of the BMP and the BMP cannot be relocated or raised in elevation to achieve a 3 foot or greater separation from bedrock or groundwater
- Contaminated soil, contaminated groundwater, or hotspot runoff is present on the site and cannot be isolated or mitigated
- Soils on the site have an infiltration rate of less than 0.2 inches per hour, the BMP cannot be relocated to areas with a higher infiltration rate, and the BMP cannot be sized to drain within 48 hours (24 hours in locations that are tributary to trout streams)
- Soils on the site have an infiltration rate greater than 8 inches per hour, the BMP cannot be relocated to an area with an infiltration rate lower than 8 inches per hour, or the subgrade cannot be modified to slow the infiltration rate to less than 8 inches per hour
- If no, go to Box 60
- MIDS design sequence flow chart - Box 55 - Do the following conditions apply?
- There are existing or proposed structures or infrastructure that make FTO 2 not feasible; and
- BMP relocation is not feasible
- MIDS design sequence flow chart - Box 56 - Select Flexible Treatment Option (FTO) 2
- No infiltration practices allowed
- Explore non-infiltration volume reduction practices
- Provide DWSMA or well location map
- MIDS design sequence flow chart - Box 57
- MIDS design sequence flow chart - Box 58 - Is Flexible Treatment Option (FTO) 2 feasible?
- MIDS design sequence flow chart - Box 59 - Do the following conditions apply?
- There are very high infiltrating soils (more than 8 inches per hour) on the site; and
- BMP relocation to an area with lower infiltration rates is not feasible; and
- The subgrade cannot be modified to slow the rate to less than 8 inches per hour.
- MIDS design sequence flow chart - Box 60 - Do the following conditions apply?
- There are adverse hydrologic impacts from infiltration practices; and
- The BMP cannot be relocated to avoid adverse hydrologic impacts; and
- BMPs accomodating FTO 1 would avoid adverse hydrologic impacts
- MIDS design sequence flow chart - Box 61 Do any of the following conditions apply? (NOTE: If any condition applies, you do not need to answer the remaining questions.)
- The site is located within a DWSMA, wellhead protection area or within 200 feet of a drinking water well and infiltration is not allowed by the LGU
- Karst is present within 1000 feet of the site and the BMP cannot be reloacted so that it is more than 1000 feet from karst
- Shallow groundwater or shallow bedrock is present within 3 feet of the bottom of the BMP and the BMP cannot be relocated or raised in elevation to achieve a 3 foot or greater separation from bedrock or groundwater
- Contaminated soil, contaminated groundwater, or hotspot runoff is present on the site and cannot be isolated or mitigated
- Soils on the site have an infiltration rate of less than 0.2 inches per hour, the BMP cannot be relocated to areas with a higher infiltration rate, and the BMP cannot be sized to drain within 48 hours (24 hours in locations that are tributary to trout streams)
- Soils on the site have an infiltration rate greater than 8 inches per hour, the BMP cannot be relocated to an area with an infiltration rate lower than 8 inches per hour, or the subgrade cannot be modified to slow the infiltration rate to less than 8 inches per hour
- If no, go to box 57
- MIDS design sequence flow chart - Box 62 Do any of the following conditions apply? (NOTE: If any condition applies, you do not need to answer the remaining questions.)
- The site is located within a DWSMA, wellhead protection area or within 200 feet of a drinking water well and infiltration is not allowed by the LGU
- Karst is present within 1000 feet of the site and the BMP cannot be reloacted so that it is more than 1000 feet from karst
- Shallow groundwater or shallow bedrock is present within 3 feet of the bottom of the BMP and the BMP cannot be relocated or raised in elevation to achieve a 3 foot or greater separation from bedrock or groundwater
- Contaminated soil, contaminated groundwater, or hotspot runoff is present on the site and cannot be isolated or mitigated
- Soils on the site have an infiltration rate of less than 0.2 inches per hour, the BMP cannot be relocated to areas with a higher infiltration rate, and the BMP cannot be sized to drain within 48 hours (24 hours in locations that are tributary to trout streams)
- Soils on the site have an infiltration rate greater than 8 inches per hour, the BMP cannot be relocated to an area with an infiltration rate lower than 8 inches per hour, or the subgrade cannot be modified to slow the infiltration rate to less than 8 inches per hour
- If no, go to Box 49
- MIDS design sequence flow chart - Box 63
- There are adverse hydrologic impacts from infiltration practices; and
- The BMP cannot be relocated to avoid adverse hydrologic impacts