ABSTRACT
A multi-purpose colonization chamber is described for examining microbial community activity within streambed hyporheic and parafluvial regions, particularly where cherty or cobbly sediments prohibited standard coring techniques. The chamber allows 1) sampling of water chemistry and biofilm-colonized sediments from three depth intervals and 2) in situ time-course experiments with minimal disturbance within shallow groundwater environments beneath and adjacent to streambeds.