Purpose and Background

As the National Pollutant Discharge Elimination System (NPDES), state and local water quality management regulations increasingly limit impacts to receiving water, stormwater management and the use of Best Management Practices (BMPs) have become a primary design consideration for most civil engineering projects in the U.S. Many states provide stormwater BMP design guidance documents to aid engineers with the selection and proper design of many types of structural BMPs. However, with the variability of soils, topography and other design constraints that occur between sites, it is often difficult to determine which BMP will be the most appropriate and cost effective solution. This webinar will review guidance documents and use example projects to demonstrate how to determine when a site is appropriate for the utilization of dry bottom infiltration basins that rely on in-situ soils for stormwater quantity and quality treatment.

Learning Outcomes

Upon completion of this course, you will be able to:

• Identify sites that are well suited for the use of infiltration BMPs that rely on appropriate in-situ soils
• Recognize primary design considerations
• Determine treatment volume and account for runoff volumes from storms that exceed the design storm
• Explore limitations of the use of infiltration basins through design examples and real world challenges

Webinar Benefits

• Learn how to find sources for design guidance
• Improve understanding of infiltration basin design
• Gain understanding of how soils, water table and other site constraints govern design
• Become familiar with treatment volume determination and bypass methods
• Solidify concepts through example projects

Assessment of Learning Outcomes

Students' achievement of the learning outcomes will be assessed via a short post-assessment (true-false, multiple choice and fill in the blank questions).

Intended Audience

This webinar will benefit stormwater and civil-site engineers, Engineers in Training (EIT’s), environmental planners and scientists, designers and technicians who work in both the private and public sector by providing a better understanding of the use and limitations of infiltration basins for the management of stormwater quantity and quality from existing and proposed built upon area.

Webinar Outline

• Determine your regulatory requirements
• Design criteria
• Soils and seasonal high water table evaluation
• Topography and other site constraints
• Design volume determination
• Bypassing excess volumes or over size the basin
• Advantages and disadvantages
• Maintenance considerations