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*Median TSS removal (all data) - 75% | *Median TSS removal (all data) - 75% | ||
*95% lower confidence limit TSS removal (all data) - 59.9% | *95% lower confidence limit TSS removal (all data) - 59.9% | ||
− | TAPE means and medians represent values meeting TAPE criteria for TP (inflow concentrations of 0.1 to 0.5 mg/L) and TSS (inflow concentrations greater than 20 mg/L). Of the | + | TAPE means and medians represent values meeting TAPE criteria for TP (inflow concentrations of 0.1 to 0.5 mg/L) and TSS (inflow concentrations greater than 20 mg/L). Of the 20 samples, TAPE medians and means represent 13 samples for TP. |
The 95% boot strap TP-removal LCL for TAPE-analyzed data was 49.9%. The LCL for all data was 19.1%, but there appeared to be multiple outliers in the dataset. The TAPE approval document noted the small median particle size (11 microns) in runoff to the device, citing multiple times when the device became clogged and required maintenance: "The system was subjected to atypical sediment loading and needed to be serviced after 4 months, or 12.7% of a water year. Monitoring personnel observed similar sediment loading and blinding issues with other systems evaluated at the Test Facility. The runoff from the Test Facility is not expected to be characteristic of other urban runoff applications". We therefore recommend using the TAPE LCL of 50% for Tier 1 TP credit. | The 95% boot strap TP-removal LCL for TAPE-analyzed data was 49.9%. The LCL for all data was 19.1%, but there appeared to be multiple outliers in the dataset. The TAPE approval document noted the small median particle size (11 microns) in runoff to the device, citing multiple times when the device became clogged and required maintenance: "The system was subjected to atypical sediment loading and needed to be serviced after 4 months, or 12.7% of a water year. Monitoring personnel observed similar sediment loading and blinding issues with other systems evaluated at the Test Facility. The runoff from the Test Facility is not expected to be characteristic of other urban runoff applications". We therefore recommend using the TAPE LCL of 50% for Tier 1 TP credit. |
Up-Flo Filter w/Filter Ribbons is is an advanced stormwater treatment system that combines sedimentation and screening with filtration. It is classified as a manufactured treatment device (mtd).
This page provides information on pollutant removal credits for Up-Flo Filter w/Filter Ribbons, links to supporting information, and links to information on system design, inspection, operation, and maintenance.
When conditions described in this section are met, applicable Up-Flo Filter w/Filter Ribbons systems are approved for the following removals for total suspended solids (TSS) and total phosphorus (TP).
For more information on credits, see TP and TSS credits and guidance for manufactured treatment devices (mtds)
Not applicable
To receive the full credit, Up-Flo Filter w/Filter Ribbons systems must comply with the following conditions.
Credits apply only to the water being treated by a device. The applicable treatment volume must be determined using one of the methods described here.
The Tier 1 credit equals the TAPE-approved credits. Tier 2 and Tier 3 credits were determined by analyzing water quality data collected at a system tested at the Lake Union Ship Canal Test Facility in Seattle, WA required servicing after 4 months or 12.7% of a water year. The site consisted of transportation land use with 22.7 acres of impervious draining to the device. The device was 18.7 ft2.
MPCA compiled data from TAPE Technical Evaluation Report generated for the site. Below are summary statistics for the device.
TAPE means and medians represent values meeting TAPE criteria for TP (inflow concentrations of 0.1 to 0.5 mg/L) and TSS (inflow concentrations greater than 20 mg/L). Of the 20 samples, TAPE medians and means represent 13 samples for TP.
The 95% boot strap TP-removal LCL for TAPE-analyzed data was 49.9%. The LCL for all data was 19.1%, but there appeared to be multiple outliers in the dataset. The TAPE approval document noted the small median particle size (11 microns) in runoff to the device, citing multiple times when the device became clogged and required maintenance: "The system was subjected to atypical sediment loading and needed to be serviced after 4 months, or 12.7% of a water year. Monitoring personnel observed similar sediment loading and blinding issues with other systems evaluated at the Test Facility. The runoff from the Test Facility is not expected to be characteristic of other urban runoff applications". We therefore recommend using the TAPE LCL of 50% for Tier 1 TP credit.
No Tier 2 or Tier 3 credit is given for this device based on data collected for TAPE certification.
TSS credit is the TAPE default of 80% since the LCL was less than 80%
The median particle size for the tested device was 11 microns, which likely accounts for the relatively poor performance compared to other mtds.
To link to the Excel spreadsheet containing water monitoring data click here
Meet the conditions specified for the appropriate TP and/or TSS credit.
Meet the following conditions, unless conditions for the appropriate TP and/or TSS credit are more stringent.
This page was last edited on 16 February 2023, at 15:30.