July 2014 monitoring

July 5, a beautiful summer day. 78 degrees, heading towards 90, sunny and humid. We’ve had more rain this summer but none in the last week, so the stream is a bit lower. All 4 columns are still in the water, though clearly the stream is a few inches lower than it has been, based on the water line. As usual, the flow from the culvert is pretty good (we’ve never seen it not flowing).  The “sometime island” rocks a ways above the waterfall were dry, and I was able to easily walk up the stream bed to them without getting my feet wet – the stream was that low.

The water level was low enough that there was no obvious current. The gravel bar just downstream of the bridge reaches across the width of the stream, the stream is low enough that there’s only a trickle flowing through a small gap in the gravel bar.

There’s scum on the surface of much of the water, and just below the waterfall – which is reduced to a trickle – there’s some white foam.. There is a fair amount of algae both on the surface and submerged (of course, excluding in the shade under the bridge). Didn’t see any fish. The columns and both walls of the bridge are “decorated” with lots of graffiti.

Observations:

air temp: 26 C (78)

water temp 25 C (77)

Dissolved oxygen – 3.3

specific conductance 590

pH 7.0

nitrate level 1 mg/l

transparency: 1.04 meters (few dissolved solids to block the light)

e-coli colony counts: higher than recommended below the culvert (612 based on 3 ml samples); the controls by the waterfall were a bit less at  349, the preferred maximum for urban streams)

 

 

sample site and downstreamlook

damp area-possible seephole from water table?

stream trickles through gravel bar closeup

closeup of stream under bridge with gravel bar (note water mark on column)

downstream view of gravel bar and stream

gravel bar and south bank

very green south bank

stream under bridge

view of downstream under bridge

culvert and stream under bridge

stream by the culvert

closeup of gravel bar

view of culvert inflow from above

looking up stream to culvert

waterfall area and above

upstream view of culvert

waterfall w white foam below it

stream with algae below waterfall

downstream view of stream and under bridge

stream around waterfall

gravel bar and under bridge

stream bend above waterfall – note the dry right bank

stream above the waterfall – the “sometime island” rocks are visible, along with the dry right bank

downstream view from above waterfall

“sometime island: rocks in the middle are completely dry, as the stream flows around them.

stream just above waterfall

dissolved oxygen – 3.6