This property owner in New Jersey had selected AQUALIS to take over the execution of their routine stormwater inspection and maintenance program. AQUALIS acquired the store from a previous stormwater contractor. During AQUALIS’ first service visit to the site, a review of the grading and drainage plans was completed, and a thorough inspection was performed throughout the entire property. A Contech Filter Vault was identified, and quickly found to be out of compliance with manufacturer guidelines. It was likely functioning in bypass mode, or not operating such that water quality and quantity rates were being achieved. In addition to an above-ground Stormwater Control Measure (SCMs), this Storm Filter system was required during the construction of the store for long-term management of a specific water quality and quantity output. This output was defined by local, state or federal jurisdiction.
In July 2017, during the service visit, AQUALIS inspectors observed significant sediment and debris build up around and on top of the filters that were located inside the underground proprietary system. Site conditions, like the soil stability or landscaping practices at the site, largely influence the large-scale maintenance cycles of filter vault systems. Heavy loads of sediment and nutrients from upstream impervious surfaces will increase the frequency of costly vault cleaning and replacement of filter cartridges. Manufacturer recommendations state that cartridge replacement should occur at 1-5 year cycles, depending on the results of the routine inspections. Filter vaults, and other underground systems, are often neglected, due to their location, if a qualified professional is not engaged to understand the design criteria and long-term needs of the entire system. Additionally, property owners do not appropriately budget for the long-term maintenance costs of these assets. The manufacturer maintains records of filter cartridge replacement, and AQUALIS found that despite this system being in place for more than ten years, the cartridges had never been replaced.
These systems need to be cleaned regularly, and often cartridges replaced, on a frequency that is dependent on the input, or sediment loading, to the system. By providing labor, equipment, and materials, AQUALIS was able to rehabilitate the Storm Filter Vault back to a functional and effective state. A vacuum and pressure washing service was performed on the Storm Filter Vault Pretreatment, Stormgate Structure, Inlet/Outlet bay, and Cartridge Bays. All of the 18″ filter cartridges were replaced, a total of 112, and the underdrain manifolds were inspected and jetted, with water reclaimed, as needed. All reclaimed material was disposed of at an approved offsite facility.
Every stormwater control measure (SCMs) is intended to have a post-construction maintenance plan to ensure the longevity of the stormwater asset; AQUALIS worked to ensure the system was compliant and functioning for the design it was intended.
Despite manufacturers recommending replacing cartridges every 1-5 years, this site was overlooked for a decade.
Editor's Note: Scranton Gillette Communications and the SGC Water Group are not liable for the accuracy, efficacy and validity of the claims made in this piece. The views expressed in this content do not reflect the position of the editorial teams of Water & Wastes Digest, Water Quality Products and Storm Water Solutions.