August 2016 monitoring

Posted by: upperwalnutcreekaustin | August 12, 2016

August 2016 monitoring

August 10 – this is about day 23 of triple digits, though if we include the “chilly” 98 degree highs the number of days would be much higher. And when considering the temperature index (humidity) – it’s been hovering around 109. Enough! Time for some highs in the low 90s! (update 8/15: wish granted. See below the first set of photos)

No rain since June, or so it seems, and the stream shows that. It is very low, definitely the lowest in quite a while. Just upstream of the bridge there’s barely a trickle flowing through the stream bed rocks. And that continues below the bridge. The waterfall is a tiny trickle, there’s some dry stream bed just above the waterfall and further upstream, the Sometime Island” part of the mid stream rocks are completely dry. I could have walked way upstream of sometime island but it’s already feeling like the mid 90’s thanks to the humidity. There’s the beginnings of lots of underwater algae everywhere, and some surface algae.

Saw a good size school of minnows above the waterfall and culvert (near sometime island). Didn’t hear or see any pigeons or other critters. Even so, the e-coli counts were high, probably because there was almost no current to move the bacteria downstream.

No surprise, the dissolved oxygen was very low.

A couple of weeks ago a car somehow crashed through the bridge side guards and landed next to the stream (how’d that happen?) . Hopefully the car occupants weren’t badly hurt, and also hopefully the stream wasn’t affected by gas etc. that may have leaked from the car.

Observations:

air temperature 29 C
water temp 28 C
dissolved oxygen 2.45
specific conductance 550
nitrates 1.0
dissolved solids > 1.2 meters
pH 7.0
E-coli was higher than recommended for an urban stream at about 1640 colonies (3 ML sample)

: looking downstream from sample site

: sample site from north bank

: stream under bridge to sample site from north bank

: under bridge to sample site from north bank

: trail crossing to sample site from north bank

: very low stream by bridge

: clear shallow water by trail crossing

: all 4 dry bridge columns

: 2 bridge columns dry

: upstream view from under bridge

: damaged hike bike rail

: south bank upstream bridge side with damaged rail

: crash area

: debris from car crash

: debris from crash

: stream with algae upstream side of bridge

: stream and under bridge from above culvert

: waterfall and upstream

: stream above bridge

: storm culvert from south side of stream

: steam and south bank from above culvert

: waterfall area very low flow

: waterfall area very low flow

: dry rock just above waterfall

: downstream view of waterfall area

: inlet above waterfall completely dry

: downstream view from inlet

: extensive underwater algae

: school of minnows in middle of stream above dry inlet

: downstream view from above waterfall

: dry sometime island rocks

: downstream view from near sometime island

: dissolved oxygen 2-4

8/15 – be careful what you wish for… Since yesterday we’ve had several inches of rain, and the creek shows it. The first 3 photos are from upstream by the appropriately named Waters Park Rd and around the corner at the Adelphi Ln low water crossing.