The Gowanus Canal and Newtown Creek are industrial waterways in New York City. Both are heavily polluted, and both were formerly parts of tidal salt marshes. Centuries of development have altered everything about the landscapes of Newtown and Gowanus. They're edged with bulkheads instead of reeds, their tributaries are now sewers, and the mill ponds, copper plants, and coal works are long gone. The tides persist, an ever-present daily pattern of shifting water levels, driving invisible flows in the water tables around the canal and creek. Inspired by @riverthames, these twitter bots speak in the first person, cajoling you to come see the tide, to look carefully and closely.

The twittering waterways' knowledge is drawn from NOAA tide tables.

My next high tide is in 55 minutes. I'll be 28 inches above average.

— Gowanus Canal (@therealgowanus) September 6, 2016

My next low tide is in 45 minutes. I'll be 24 inches under average.

— Newtown Creek (@newtown_creek) September 6, 2016