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→Continuous Monitoring
*[http://archive.phillywatersheds.org/ltcpu/GCCW%20Comprehensive%20Monitoring%20Plan%20Sections%201-10.pdf Green Cities, Clean Waters Comprehensive Monitoring Plan, Appendices C and D] (City of Philadelphia, 2014)<ref name="example4">. City of Philadelphia. 2014. Green City, Clean Waters: Comprehensive Monitoring Plan. The Philadelphia Water Department. Philadephia, PA. http://archive.phillywatersheds.org/ltcpu/GCCW%20Comprehensive%20Monitoring%20Plan%20Sections%201-10.pdf</ref>
*[http://archive.phillywatersheds.org/ltcpu/GCCW%20Comprehensive%20Monitoring%20Plan%20Sections%201-10.pdf Green Cities, Clean Waters Comprehensive Monitoring Plan, Appendices C and D] (City of Philadelphia, 2014)<ref name="example4">. City of Philadelphia. 2014. Green City, Clean Waters: Comprehensive Monitoring Plan. The Philadelphia Water Department. Philadephia, PA. http://archive.phillywatersheds.org/ltcpu/GCCW%20Comprehensive%20Monitoring%20Plan%20Sections%201-10.pdf</ref>
===Drainage Performance Evaluations ===
===Drainage Performance Evaluations===
It is recommended that at a minimum, the drainage performance of stormwater infiltration BMPs be evaluated as part of Assumption and Verification inspections. Drainage performance, or the ability of the BMP to fully drain runoff from a certain size storm event within a certain time period, can be evaluated by continuous monitoring during natural or simulated storm events. When a water source of sufficient size to fill the sub-surface water storage reservoir is available, it is recommended that drainage performance evaluations be performed by simulated storm event testing as results can be produced within a much shorter time period (e.g., within a week) as opposed to natural storm event testing, which can require field monitoring activities over 6 months to 2 years in duration.
It is recommended that at a minimum, the drainage performance of stormwater infiltration BMPs be evaluated as part of Assumption and Verification inspections. Drainage performance, or the ability of the BMP to fully drain runoff from a certain size storm event within a certain time period, can be evaluated by continuous monitoring during natural or simulated storm events. When a water source of sufficient size to fill the sub-surface water storage reservoir is available, it is recommended that drainage performance evaluations be performed by simulated storm event testing as results can be produced within a much shorter time period (e.g., within a week) as opposed to natural storm event testing, which can require field monitoring activities over 6 months to 2 years in duration.
*a perforated standpipe on the BMP surface to measure the time required to drain water ponded on the surface (i.e., the surface water storage reservoir component) and estimate filter bed surface infiltration rate; and,
*a perforated standpipe on the BMP surface to measure the time required to drain water ponded on the surface (i.e., the surface water storage reservoir component) and estimate filter bed surface infiltration rate; and,
*a monitoring well screened within the sub-surface water storage reservoir component of the BMP
*a monitoring well screened within the sub-surface water storage reservoir component of the BMP
===Simulated Storm Event Test Procedures===
For infiltration BMPs designed with flow-restricted sub-drains, continuous monitoring to evaluate drainage performance should be performed by conducting a simulated storm event test using the following stepwise procedure below:
#Select a date for the test when no rainfall is forecast for at least 3 days.
#Install flow monitoring apparatus downstream of the sub-drain flow restrictor device.
#Temporarily plug the sub-drain pipe.
#Direct enough water to the BMP to completely fill the sub-surface water storage reservoir.
#Remove the sub-drain plug.
#Allow the BMP to fully drain.
#Determine the maximum flow rate from the sub-drain from flow measurements
#Determine the drainage time from the water level measurements
#Calculate the infiltration rate based on water level measurements once flow from the subdrain has stopped as the change in storage volume over time divided by the infiltration area.
#If more than 13 m<sup>3</sup> of water (i.e., the typical capacity of water tanker trucks) is needed to fill the sub-surface water storage reservoir, a fire hydrant will need to be used as the water source.
For infiltration BMPs that contain unrestricted sub-drains, continuous monitoring to evaluate drainage performance should capture the full drainage periods for at least one storm event large enough to completely fill the sub-surface water storage reservoir to the elevation of the sub-drain pipe invert or at least 3 rain events between 15 and 25 mm in depth.
*Mean values for drainage time and infiltration rate should be calculated and compared to design specifications or regulatory criteria to determine if the BMP is draining at an acceptable rate.
*Alternatively, a simulated storm event test can be performed, using the stepwise procedure described above.
For further in-depth details on continuous monitoring best practices
==Green Roof Irrigation System Testing==
==Green Roof Irrigation System Testing==