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Monthly Image: Still Water at Red Oaks Mill Dam

We walked past the Red Oaks Mill dam on a mild and dead-calm afternoon, with the headwater like a mirror:

Red Oaks Mill Dam - still water

Red Oaks Mill Dam – still water

I liked the smooth curves formed where the surface drops through the rubble:

Red Oaks Mill Dam - water curvature at breast

Red Oaks Mill Dam – water curvature at breast

We wonder how far upstream the dam affects the water level, because, after it completely disintegrates and washes away, the creek level will definitely fall. The flow rate surely makes the calculation more difficult than just tracing contour lines from the dam breast upstream until they meet the bottom of the channel…

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  1. #1 by Red County Pete on 2015-12-15 - 09:39

    Is there a differential GPS project in the making? [grin] Robotic floating rover FTW! A survey crew used a dGPS on a boat when they built a new bridge nearby, but I don’t know if the accuracy/precision would be better than the effect you want to measure.

    • #2 by Ed on 2015-12-15 - 12:08

      We went to a talk by one of the surveyors who measured the ironwork before & during the Walkway Over the Hudson project: they cross-checked the differential GPS results with chains and laser rangefinders, only to find that it’s basically as good as you can get and a whole lot faster.

      After that dam washes away, maybe the Canoe Race can run from Pleasant Valley all the way to Lake Wappinger. Bit rocky in the middle, but they can always portage…