Performance Assessment of the Environment21 V2B1 Model 4 for Removing Suspended Sediments from Stormwater

Environment 21 requested a series of tests to be conducted on their V2B1 Model 4 hydrodynamic separator. A V2B1 Model 4 was brought into St. Anthony Falls Laboratory (SAFL) and set up for testing. Four series of tests were conducted. The first two series of tests were to meet the New Jersey Corporation for Advanced Technology (NJCAT) requirements for assessing the V2B1 Model 4 efficiency in removing suspended sediments and scour potential. The third test series was to determine the performance function of V2B1 Model 4 and the fourth test series was a repeat of the NJCAT requirements with some modifications to the test procedure and design flow, which were all discussed with the New Jersey Corporation for Advanced Technology (NJCAT) representative. The main change in the fourth test series was to preload the sump and to use load cells to determine the removal efficiency of the device while the materials in the sump were subject to resuspension. The first, second, and third test series are described in a separate report. The report herein is a summary of the test setup, the test procedure and the results of the fourth test series. The results of the fourth test series showed that V2B1 Model 4 is on average capable of removing 65% of the suspended sediments with the particle size distribution and runoff hydrograph recommended by the NJDEP.