October 2018

October 13 – a warm, overcast and muggy day (85% humidity – yuk!). The forecast for tomorrow night is 40 degrees lower as a cold front sweeps through. I’m ready!

Meanwhile, the stream is noticeably higher after 2″ of rain in the last 2 weeks, and there’s some new debris caught just above the current stream level. And more trash by the creek/culvert that flows from the parking lot. We really needed the rain, so no complaints. Just a curiosity: by the sample site there’s now a piece of blue cloth (tarp?) hanging from a branch. Don’t recall seeing that last time – how high was the water during the recent rains?

Among other changes, the higher flowing water removed all of the surface algae and even scoured all of the submerged algae – it’s all gone. We didn’t see any fish, turtles or birds. The water was high enough that the trail crossing was submerged. Looks like the higher flow carved a bit of a new channel on the upstream side of the bridge as that column was out of the water with other areas being a bit more covered. And since we couldn’t cross with dry feet, we didn’t check out what appears to be additional debris a ways downstream of the sample site (can’t get there from the north bank). Maybe we’ll check it out next month.

The waterfall was flowing much stronger, stretching the full distance across its width for the first time in months. Further upstream, part of the inlet that’s been bone dry lately was under water, and all of it was very muddy – clearly the stream had been much higher. I couldn’t walk up much past that without wet feet so didn’t go near to the “sometime island” rocks in the middle of the stream. At best they might be slightly out of the water.

The e-coli average count for 3 ML samples were 249 colonies at the sample site and 233 at the upstream control, both are within acceptable limits for an urban stream.

Observations:

air temp: 25 C
water temp 23 C
dissolved oxygen 5.7
specific conductance 450
pH 7.0
transparency (dissolved solids)  > 1.2 meters
nitrates 0.3

 

sample site from north bank

sample site and beyond from streamside

new debris downstream of sample site

high water dbris near sample site

trail crossing wet

stream from under bridge to trail crossing

downstream side of stream at bridge

closeup of trail crossing area

stream under bridge

stream under bridge and beyond

low water upstream bridge side

upstream view from under bridge

stream from atop culvert

waterfall area and beyond

waterfall closeup

faster flowing water near waterfall

above waterfall

downstream view from inlet

sometime island rocks near surface

mostly dry inlet above waterfall

dissolved oxygen 5-7