Healthy Rivers are Messy

Wednesday, November 13, 2019
Place name or River name: 
MassDOT Rivers and Roads
RiverSmart Communities' stream table

Messy Rivers are Healthy Rivers. In November 2019, RiverSmart Communities' stream table traveled with MassDOT's Rivers and Roads training program, teaching about how rivers work. In this time-lapse of a stream table demo we let the river carve its own channel into unconsolidated open material. It goes everywhere! We use toothpicks to mark where meanders move. The channel migrates and braids downstream, and even avulses to form new channels when large flows occur. 1 minute in stream-table time represents approximately 2 years of channel evolution, so this 15-minute span condensed to the first 15 seconds represents approximately 30 years. Next, we create a more natural river: we connect it to the surrounding floodplain, add trees, logs, rocks and wildlife. Now the river can flood onto its floodplain, slowing down and depositing sediment there. This creates a river that presents fewer hazards to human settlements while supporting healthy river ecosystems.