W. CONSHOHOCKEN, PA. — Stormwater hydrodynamic (HDS) systems are used to remove settleable solids that could cause contamination from stormwater runoff. A proposed new ASTM International standard will be used to specify test material with a common target particle size distribution for use in testing HDS systems.

The proposed new standard, ASTM WK39909, Specification for Surrogate Test Solids for Measuring Performance of Stormwater Treatment Devices, is being developed by Subcommittee C27.70 on Precast Concrete Products for Stormwater Management, part of ASTM International Committee C27 on Precast Concrete Products.

Adam Stevens, research technician, CONTECH Engineered Solutions, and a C27 member, says that one of the desired outcomes of laboratory evaluations of treatment technologies is the ability to make direct comparisons among technologies. To achieve this, all devices must be tested in the same manner, using the same surrogate pollutants. The proposed standard will allow regulatory agencies to have the option to adopt such surrogates into their existing testing protocols; they will no longer need to address possible market discontinuance or later revision of their protocols.

“Ultimately, the proposed standard is intended to ensure that these types of treatment systems are consistently meeting established treatment benchmarks,” says Stevens. “This ties back to the overarching goal of protecting and restoring receiving waters."

The primary users of ASTM WK39909, once it has been approved, will be regulatory agencies establishing testing protocols, manufacturers of HDS systems evaluating performance, as well as independent and university laboratories carrying out testing regarding manufacturers’ claims.

All interested parties are invited to contribute to the development of ASTM WK39909. Stevens would particularly like to locate laboratories that can carry out full-scale solids removal testing of HDS systems.