Snow accumulation progressing

Snow depth at the larch site (see above) had almost doubled since the last survey in mid-January. Depth now 111cm, density unchanged at 0.3, and snow water equivalent 33.6cm.

Snow survey at a nearby mountain location (elevation 200m, see below) revealed almost identical SWE, although the density was slightly lower and snow depth correspondingly higher.

Snow survey and lysimeter check

Snow survey at the larch site revealed average depth 66cm, average density 0.31, and snow water equivalent of 20.3cm at this low elevation location near the stream gauge.

Lysimeter drains were dug out to remove debris from the drain plug and ensure free drainage before replacing the snow cover.

First snow survey

Trace snowpack of 10-20cm depth was measured around the stream gauging location. The snow lysimeter experiment was set up for one last time before likely decommissioning next spring.

New local logging activity

The above hydrograph shows that there are frequent rainfall events during November, with two significant peaks of about 0.6m to 0.7m stage (maximum daily rainfall of 37.5mm on 21 Nov.).

Below you can see that some local logging activity has begun close to the gauging station. The impact on the ground and soil of the caterpillar tracked felling machine appears to be rather severe, and does not compare well to the traditional aerial yarding technique which I witnessed being practised here about 20 years ago.

Autumn rains kick in

Big change in the situation of the basin since late October. Over the period of a week the river stage rose from about 0.3m (low flow) to 0.8m (moderate high flow) due to continuing and unusually heavy rainfall (190mm total with maximum intensity of 16.5mm/h).

October - new water year

First field trip since the start of the new water year on 1st October. The 1st October begins with low flow conditions, but the first autumn rainfall event of the new water year arrives with a small peak flow.

Stage data was downloaded for both sensor systems - the Kadec/Druck and Hobo systems. The photos below show the Hobo logger attached to the same support pipe as the staff gauge, within a grey PVC casing.

September wetter than usual

Early September began wetter than usual and another powerful typhoon (#24) is due to arrive around 30th September. Today's discharge measurement was 0.975 m3/s at 0.425 m stage, which fit exactly on the current rating curve.