answers from Chicago on. Very tiny bugs coming up the drain that hop a little are probably springtales...I goggled tiny little bugs that hop when I first encountered them and that's what came up.
Detention basin. A detention basin or retarding basin is an excavated area installed on, or adjacent to, tributaries of rivers, streams, lakes or bays to protect against flooding and, in some cases, downstream erosion by storing water for a limited period of time.
Drainage Basins - Each stream in a drainage system drains a certain area, called a drainage basin (also called a catchment or a watershed). In a single drainage basin, all water falling in the basin drains into the same stream. A drainage divide separates each drainage basin from other drainage basins.