Soil moisture monitoring shows infiltration of rainfall occurred late summer — Middle Colorado #WaterQuality Digest #ColoradoRiver #COriver #aridification

Click the link to read the report on the Middle Colorado Watershed Council website (SGM):

The precipitation gages within the canyon have been up and running all summer, reporting rainfall every five minutes.  In mid-June, soil moisture sensors were collocated with 4 of the rain gages.

The chart below shows the precipitation and soil moisture from the Deadman’s Creek location. Prior to the rainfall the week of August 14, the soil moisture content was not reactive to the smaller rain events. Several storms during the week of August 14 dropped significant rain at the Deadman’s Creek rain gage. The final storm on August 16 dropped enough water to finally infiltrate down to the depth of the soil moisture sensor and cause a measurable change in the soil moisture content.

The storm events on August 20 through August 21 again increased the soil moisture at Deadman’s Creek. So far, no debris flow events have been triggered due to over saturated soil conditions.

Turbidity remained high through summer in Colorado River and returns to normal levels second half of September 

Since the end of August, the turbidity in the Colorado River has slowly been trending downwards. With no major debris flow events the last week of August or in September, the turbidity has remained under 200 FNU.

The turbidity has finally returned below 20 FNU in the last two weeks of September. While we do not know exactly why the base level of turbidity in the water has remained elevated all season, it may be due to continuous re-mobilization of sediment from previous debris flow piles and from sediment that has settled previously within the riverbed.

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