Know Your Flows Gary Webber, MRWA Wastewater Technician Throughout the years many of us have heard folks say in conversations, “Small Things Matter”. This applies to many things in life, and it is no different at the wastewater utility. There are fundamental items that demand accurate attention on a scheduled basis. Flow to or from the wastewater treatment facility is one of those small things that really matters. There are several reasons for accurate flow measuring. Without knowing your true flows, it can cost your permitted facility a lot of grief and expense. One must ask themselves; how would an engineer ever design or size anything at the treatment facility or collection system if flow measurements were not accurate or representative of conditions based on customer use and/ or Mother Nature’s influence?
know your flows. There are too many flow conditions that need recorded on a consistent basis to capture the many different flow variations most collection systems and treatment facilities experience. Flow measuring systems that log data work great in capturing flow information if they are installed and calibrated correctly. So, having a manual flow measuring device helps one determine if there is a calibration issue with the equipment. Lift station run times and drawdown tests can also help measure flows to an extent. The bottom line is, there needs to be some method of determining accuracy with newly installed, temporary, or unproven flow measuring equipment. Once you are confident with the information being recorded then let the data logger go to work.
Flow measuring devices come in a lot of different types and styles and are essential in providing accurate data. It would be great if every facility was equipped with a data logging system to record flows around the clock every day of the year. For some systems just having a V-Notch Weir to manually measure flows would be an improvement. Using a flow measuring device to calculate flows every once in a while, is not a responsible way to
Open Channel Flow Meter
Once the installation is in place one can determine how fast flows increase or decrease. You can record your true peak flows and low flows in the middle of the night. Dry Weather Flows and Wet Weather Flows can be determined with ease. One should be sure to take care when transferring data to the utilities eDMR Sheet online. If it asks for flows to be recorded in million gallons V-Notch Weir
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