Stormwater360 been operating a rapid bio-filtration device trial at the Auckland Botanic Gardens since 4th July 2016.
During the past 12 months, plant growth and the infiltration rate of the Filterra® BioRetention System has constantly been monitored.
Using three different test methods – single ring, double ring and hydrant testing, the Filterra® has been shown to consistently operate above its design infiltration rate of 2190 mm/hr.
The device was recently given a full maintenance clean after the large storms that hit the Auckland region in March/April 2017.
Maintenance involved assessing plant health, litter and weed removal, and replacement of the sacrificial mulch layer.
It was observed during the maintenance that the mulch had captured a large amount of sediment, preventing occlusion of the filter media. The Filterra® mulch provides a pre-treatment element to the system.
The Filterra® is easily maintained by a single-person without the need for a sucker truck or confined space entry.
After maintenance was performed the system was tested with a fire hydrant and was operating at 125% of design flow rate - the media was found to flow at 2740 mm/hr.
The device continues to be tested every three months.
For more information on Filterra® please contact sales@stormwater360.co.nz