April 2019

April 14, an absolutely gorgeous day! Sunny and cool, quite a change from yesterday’s morning rain and late afternoon high winds, gusting up to 50 MPH.

The stream was clear, especially given yesterday’s rain of about 1/3 of an inch and a week ago 4 inches of rain in one day. The resulting flow from that heavier rain was enough to remove all the surface algae and much of the submerged algae, which has begun to regrow. It also completely eliminated the remaining gravel bar in the stream under/downstream of the bridge and removed the rocks someone placed in the water by the trail crossing so hikers could cross with dry feet. Now to cross requires wading.

The stream is slightly higher than last month, and water is noisily flowing over the full width of the waterfall, rather than over just a part of it. The stream extends a bit into the inlet above the waterfall, and it looks like the “sometime island” rocks further upstream are covered. And just upstream of the bridge it’s not possible to walk to the other bank with dry feet unless you can do a long jump. Even so, two of the bridge columns are completely out of the water. The stream’s main channel is now between them and the south bank, as it has been since the construction for the hike and bike trail.

We saw a school of gambusia (minnows) in the shallow area near the sample site and trail crossing. No pigeons (possible e-coli source) or other birds. The “cat” that we’ve seen the last 2 visits sitting atop the upper bridge supports was still there. A passerby said it looked more like an owl with tufted ears – it’s high enough that due to the angle of sight its body isn’t visible. That makes more sense, I’ve always wondered how a cat could climb the vertical concrete pillars to reach that perch.

The e-coli 3 ml sample at the site had 166 colonies, the control site above the storm culvert was slightly higher at 233 colonies.

Observations:
air temperature 15.5 C
water temperature 15 C
dissolved oxygen 8.5
specific conductance 490
pH 7.0
Nitrates < 0.3
transparency 1.1 meters

sample site from streamside

sample site from north bank

trail crossing area

stream from bridge to trail crossing from north bank

stream from bridge to trail crossing

stream by bridge no gravel bar

downstream view of water from under bridge

stream and columns under bridge

upstream side of bridge

stream from above culvert

view upstream from under bridge

stream and waterfall area

waterfall

upstream view from waterfall

downstream view from above inlet

upstream of inlet

submerged algae clumps near inlet

submerged algae by inlet

sometime island area

dissolved oxygen 8.9