December 2017 monitoring

Dec. 9 – the wacky weather continued this week. Tuesday reached a record high of 85 degrees. Then Thursday evening we had SNOW! Near this site there was about an inch of snow; some of it lasted until mid morning on Friday.

The stream was slightly higher than usual, there was a bit of water at the entrance to the inlet above the waterfall. And water was flowing across nearly the entire width of the waterfall. There was very little surface algae. On the upstream side of the bridge the water fully covered the stream bed, and on the downstream side it would have taken a very long step to cross with dry feet. All 4 bridge columns were completely in the water.

The water was crystal clear.

We saw a good-size turtle and some water walkers at the sample site but still no pigeons or other birds. The dissolved oxygen was 9.1, much higher than it has been in months. Of course, the water temp was only 9 degrees C (48 F), so the higher DO number is to be expected – colder water holds more oxygen than warmer water.

Observations

air temp 12C (53 F)
water temp 9C (48 F)
dissolved oxygen 9.1
specific conductance 440
pH 7.0
transparency > 1.2 meters
e-coli 266 colonies (acceptable for an urban stream)

view of sample site from north bank

sample site and downstream from streamside

view of bridge area from north bank

waterfall area

stream by trail crossing

downstream view from under bridge

trail crossing area

all 4 columns in the water

upstream side of bridge

stream from culvert to bridge

stream from above culvert

waterfall

general upstream area

downstream view from above inlet

inlet above waterfall has a bit of water

above waterfall and inlet

stream above waterfall and inlet