Sediment Level Monitoring System for Stormwater Management Facilities

July 18, 2016

By Thomas R. Decker, P.E., M.S.C.E.

An efficient way is required to monitor and maintain stormwater management (SWM) facilities such as manufactured treatment devices (MTDs). MTDs are installed underground as a SWM measure to capture total suspended solids (TSS) in stormwater to provide for water quality treatment. Over time, the sediment load accumulates and fills the device and requires cleaning. The maintenance requires a physical presence at the MTD by maintenance personnel to measure or view the sediment levels. Patent No. US 8,924,167 implements a system approach at SWM facilities that will automatically detect the sediment level using sensors allowing an efficient way to determine when cleaning is required. The system will send a signal to a remote location or web site so that the owner can review the information to direct the appropriate maintenance activities. The web site or data will also serve as a database to keep track of the SWM facilities and an inventory to keep cleaning records or note any maintenance activities required.

The sediment load varies so it is often difficult to estimate or evaluate the level or rate of sediment accumulation. The MTDs manufactures and regulatory agencies also typically require very frequent monitoring of the SWM facilities, particularly in the first few years of service. This is costly plus time consuming and may not provide an accurate indication of the future TSS load. Use of roadway sanding operations, upstream development, weather, storms and general human activity that changes and varies over time impacts the sediment load. Short term and long term maintenance costs are understated because they do not include mobilization, heavy equipment rental, and mileage costs.

The use of the Patent US 8,924,167 system will automate the process and ultimately save money over time.

Limited land for development, especially in urban areas often dictates the desire to use underground SWM facilities. There are also future needs to retrofit existing SWM systems with MTDs in urban areas or in areas where the waterways are impaired to help improve the health of the waterway and ecosystem. This will also lead to the need for better maintenance of SWM systems.

The owner and governmental agency, along with the Regulatory Agency may be provided access to the database to monitor inspections and insure compliance with any permit conditions.

Establishment of an easier and sound way to facilitate maintenance can also be used by owners and more importantly regulatory agencies to require that new better robust measures be used which will encourage better acceptance of the use of underground SWM facilities such MTDs.

Information on the performance of new technologies is critical to state environmental protection efforts. Regulatory standards and permits often rely on technology performance data. Unfortunately, few, if any, standardized methods have been established for the sediment measurement and maintenance technologies across the states. Therefore, one primary goal of Patent US 8,924,167 is to have the Regulatory agencies encourage or mandate use of the system in the future.

For information, please contact Thomas Decker at [email protected].