What you can't capture and infiltrate.
In most cases, infiltration based practices are sized to capture and infiltrate the 1.25" rain or less. However, sometimes it rains more than that in a 24 hour period. That means that you could have a series of BMPs or a stormwater treatment train to capture and treat even more stormwater.
Some simple stormwater treatment trains may consist of the following:
- rain barrel to rain garden to native landscaped area
- rain garden to a Bioswale: Design & Specification to a neighborhood detention or retention pond