What Proprietary Stormwater Quality Treatment Devices Are Currently Allowed?

The following proprietary stormwater quality treatment devices are currently accepted for use in Sacramento County:

• CONTECH Stormwater Solutions StormVault®
• CONTECH Stormwater Solutions StormFilter® (1 gpm/ft², ZPG media)

Since the late 1990's, the Sacramento Stormwater Quality Partnership has been conducting a study to investigate the performance of proprietary stormwater quality devices. In November 1999, they published the Investigation of Structural Control Measures for New Development. The report documents the protocol that must be followed in order for a particular device to be accepted for use in the Sacramento area. Manufacturers have been invited on several occasions since then to submit data which could be reviewed for conformance with the protocol, but to date, only one proprietary stormwater quality treatment device has successfully met the protocol: Stormvault by CONTECH Stormwater Solutions®. Site designers proposing to use this device need to submit sizing calculations to the local permitting agency (software is supplied by the manufacturer for this purpose).

In addition to devices accepted using the Sacramento area protocol, the Sacramento Stormwater Quality Partnership (Partnership) will accept technologies with the Washington State Department of Ecology's General Use Level Designation for Basic (TSS) Treatment on a case by case basis. Refer to Ecology's Evaluation of Emerging Stormwater Treatment Technologies for more information on their technology evaluation program and protocols. As of January 25, 2006, the Partnership has accepted the StormFilter by CONTECH Stormwater Solutions®. Only the model containing ZPG (zeolite/perlite/granular activated carbon) mix approved for basic treatment at 1 gpm/ft² is approved. Site designers proposing to use the device need to submit sizing calculations to the local permitting agency. Note that other media or higher flow rates will not be accepted.

Note that no other proprietary treatment devices are approved at this time.

Site designers proposing to use either the Stormvault or the StormFilter shall include the following items (to scale) on the improvement plans:

• Plan view of device & appurtenances on the civil site plans
• Section view of device & appurtenances in reference to other utilities
• Detail drawings of device & appurtenances
• Specifications and installation notes.

Currently, the City & County of Sacramento do not allow these types of proprietary stormwater quality treatment devices to be installed in the public right-of-way or in areas where the local agency would be required to conduct maintenance. Other local agencies may or may not allow this; check with your permitting agency for verification.

In select cases, the local permitting agency may allow the use of alternative proprietary treatment measures as a "pilot study." In such cases, the property owner and/or manufacturer will be required to fund and complete a monitoring study to verify the device's performance. Since approval is not guaranteed, site designers proposing to use an alternative technique should coordinate with the permitting agency early in the site design process.

The local agencies periodically update their protocol as new study results and data become available. Questionnaires are periodically sent to manufacturers requesting any new pollutant removal effectiveness data for submission and evaluation. If you would like your company’s information added to our mailing list, please contact Dalia Fadl or Sherill Huun. This web site will be updated if any additional proprietary devices are found to meet the agencies' protocol.