2021 Kitsap County Stormwater Design Manual
2021 Kitsap County
Stormwater Design Manual

5.4.30 Manufactured Treatment Devices as BMPs

5.4.30.1 BMP Description

To receive Ecology approval for use in stormwater applications in Washington, new technologies shall be evaluated following Ecology’s technology assessment protocols (TAPE and CTAPE), which establish guidelines for evaluating the performance of runoff treatment technologies in achieving different levels of performance (i.e., pretreatment, basic, enhanced, phosphorus, oil). The evaluation process requires manufacturers to field test the performance of new runoff treatment technologies. After the successful completion of field testing, the vendor submits a technology evaluation report (TER) to Ecology for review and approval. Information about Ecology’s evaluation process can be found on Ecology’s TAPE web page.

Under the technology assessment process, Ecology assigns “Use Level Designations” to assess levels of development for manufactured treatment devices and BMPs. The use level designations established by Ecology are based on the quantity, quality, and type of performance data. There are three use level designations:

  • GULD – General Use Level Designation: A General Use Level Designation (GULD) is assigned to technologies for which the performance monitoring demonstrates with a sufficient degree of confidence, that the technology is expected to achieve Ecology’s performance goals. Use is subject to conditions, including design restrictions and sizing, documented in a use level designation letter prepared by Ecology.

  • CULD – Conditional Use Level Designation: A Conditional Use Level Designation (CULD) is assigned to technologies that have considerable performance data not collected per the TAPE protocol. Ecology will allow the use of technologies that receive a CULD for a specified time, during which performance monitoring shall be conducted and a TER submitted to Ecology. Units that are in place do not have to be removed after the specified time period. Use is subject to conditions, including design restrictions and sizing, documented in a use level designation letter prepared by Ecology.

  • PULD – Pilot Use Level Designation: A Pilot Use Level Designation (PULD) is assigned to new technologies that have limited performance monitoring data or that only have laboratory performance data. The PULD allows limited use of the technology to allow performance monitoring to be conducted. PULD technologies may be installed provided that the vendor and/or developer agree to conduct performance monitoring per the TAPE protocol at all installations. Use is subject to conditions, including design restrictions and sizing, documented in a use level designation letter prepared by Ecology.

5.4.30.2 Performance Mechanism

Ecology has established different performance goals for runoff treatment technologies based on the types of pollutants that they are effective in removing and their applicable use for runoff treatment. Proprietary technologies use a wide variety of mechanisms to achieve these performance goals.

5.4.30.3 Application and Limitations

There are various Ecology-approved proprietary technologies that can satisfy runoff treatment requirements for pretreatment, oil control, phosphorus control, basic treatment, and enhanced treatment. Refer to Ecology’s TAPE web page for a list of approved technologies.

5.4.30.4 Site Considerations

Site considerations are dependent on the approved technology selected; Ecology’s TAPE web page and specific manufacturer recommendations.

5.4.30.5 Design Information

Design information and guidance for each specific approved technology is included on Ecology’s TAPE web page.

5.4.30.6 Minimum Construction Requirements

See the below requirements and those provided on Ecology’s TAPE web page for minimum construction requirements for manufactured treatment devices and BMPs:

  • Follow the manufacturer’s recommended construction procedures and installation instructions as well as any applicable Kitsap County requirements.

  • Follow the manufacturer’s requirements for flow rate restrictions.

  • Protect media filter systems from construction flows. Thoroughly clean structures and replace media or media cartridges if impacted from construction flows.

5.4.30.7 Operations and Maintenance

Refer to Ecology’s TAPE web page and the manufacturer’s website for BMP-specific maintenance requirements.