Analysis of the Snow Water Equivalent SWE in

Analysis of the Snow Water Equivalent (SWE) in the Logan River Watershed Paul Ackerson CEE 6440

Objective Provide evidence that SWE is related to elevation. Estimate spring runoff based on SWE buildup.

Building the Logan River Catchment Seamless data from USGS to obtain DEM Obtaining stream flowline from NHDPlus Fill Flow direction Flow Accumulation Outlet Watershed Raster to Polygon Tabulated Area (211 Mi. 2)

Logan River Basin

Snow Water Equivalent Data obtained (SWE) from NRCS 8 Station data Found average SWE for each day Took average for Feb. 1, Feb 15, Mar. 1 Mar, 15… Plotted each series with corresponding date Found that SWE was related to elevation SWE = a + bz

40 R 2 = 0. 8432 R 2 = 0. 85 R 2 = 0. 8107 R 2 = 0. 7701 Snow Water equivalent. 35 30 1 -Feb 25 15 -Feb 20 1 -Mar 15 1 -Apr 10 15 -Apr 5 0 5000 5500 6000 6500 7000 7500 Elevation (ft) 8000 8500 9000

Theory of Elevation 40 1 -Feb 35 30 15 -Feb 25 1 -Mar 20 15 -Mar 15 1 -Apr 10 5 15 -Apr 0 Tony Grove Lake USU Doc Daniel Franklin Basin Bug Lake Garden City Summit Temple Fork Klondike Narrows Tony Grove RS

Relating SWE to flow 800 3. 500 700 3. 000 Flow (cfs) 2. 500 Storage 500 2. 000 400 1. 500 300 1. 000 200 0. 500 100 0 12 -Nov 1 -Jan 20 -Feb 11 -Apr 31 -May 20 -Jul 8 -Sep 28 -Oct 17 -Dec 0. 000 5 -Feb SWE (ft) Average Daily (cfs) 600

Work to be done Interpolate the SWE over the watershed using kriging function Show relationship of SWE = a + bz in different maps at different time of the year Estimate total SWE storage for entire Logan River Catchment

Thanks! Questions?