August 2017 monitoring

August 12 – today was day 33 of 100+ degrees this summer. Although the humidity isn’t to Houston’s level, it is still very noticeable – when I walk outside I feel like I’m wrapped in a hot, damp blanket. Not fun. We had about 2″ of rain last weekend, which was wonderful. It cooled things off for a day or two but the heat quickly returned. Even at 10 AM when it’s only 30 C (86 F), the humidity makes it feel like it’s the mid 90s. Can’t wait for October, when it should cool off a bit!

The stream looks like it usually does in August – low water and low or no flow. The waterfall is barely audible; the stream only flows over a small section of it. And there is much new, bright green algae on the sides, probably from the rain last week… and the outer edges where the water has receded are already dead. By the trail crossing downstream of the bridge, the stream is so narrow it’s easy to step over and keep feet dry.

We saw some gambusia (minnows) and perch near the sample site, and I saw a large school of gambusia above the waterfall and inlet. Again no birds or pigeons.

The inflow from the storm culvert/parking lot was steady and average – it’s good to see the short tunnel under the sidewalk remains clear. Walking down to the stream next to the culvert, I noticed that a stagnant area in the culvert had a scummy surface.

Observations:

air temp 30 C
water temp 27 C
dissolved oxygen 3.4
specific conductance 450
pH 7.0
transparency tube (dissolved solids) 1.2 meters
nitrates 0.3
e-coli was acceptable for an urban stream (183 colonies per 3 ML sample)

sample site from north bank

sample site from streamside

view of stream from bridge to trail from north bank

view of stream from north bank

closeup of gravel bar

downstream view from under bridge

all 4 columns in water

upstream side of bridge

looking upstream from under bridge

storm culvert

stream from above culvert

waterfall area

waterfall area

waterfall area

closeup of waterfall and new algae

dry inlet and stream above waterfall

upstream, looking towards “sometime island” exposed rocks

low stream near “sometime island” rocks

downstream view from near “sometime island” rocks

gambusia (minnows) above waterfall

south bank greenery near exposed rocks

downstream view from above waterfall

low stream, dry “sometime island” rocks

dissolved oxygen 3.4