Spates are often considered the major abiotic disturbance that affects stream ecosystems.  Global climate change models, however, predict that temperate biomes will experience reduced and unpredictable precipitation in the future.  As a consequence, seasonal drought may become a novel and frequent abiotic characteristic of temperate stream ecosystems.
     We sought to better understand the effect that stream-wide desiccation has on benthic algal community structure.  Natural stream flora were allowed to colonize artificial substrata for 21 days in sixteen experimental stream channels in northern lower Michigan, USA.  The discharge was subsequently reduced over 7 days and eventually suspended to create a stream-wide desiccation event.  After 7 days of complete drought, water was reintroduced to the system to examine the recovery and resilience of benthic algae. We examined the relative and absolute abundances of all algal groups, and created a system to assess cell health.
     In this paper, we present data on the structure and health of the freshwater algal communities in the artificial stream ecosystems before, during, and after the desiccation event.  We offer comments on the relevance of our results relative to predictions of climate change and elevated temperatures with regard to stream primary producer communities.