DOI: 10.5061/dryad.vt4b8gtzp
title: Data from: Multiple timescales of streambed flux variability in two perennial mountain-front streams

description: Streambed fluxes are highly variable through time and space, having a
 range of implications for stream‐aquifer processes. This study
 investigated streambed fluxes over a 3‐year study period to characterize
 short‐ and long‐term variations and related implications for seepage
 recharge and hyporheic exchange. Time series of streambed fluxes were
 estimated through Darcy‐based methods using water level and temperature
 inputs from shallow (&lt;1.5 m) nested streambed piezometers installed
 in two mountain‐front streams in Colorado, USA. Three predominant temporal
 scales of variability were characterized: sub‐daily (&lt;1 day), daily
 (&gt;1 day; &lt;1 year), and interannual (&gt;1 year).
 Temporal variability was quantified using the median absolute deviation
 (MAD), a statistical measure that is resistant to extreme values
 associated with short‐duration events. Sub‐daily variability (MADS‐D) was
 related to ET, temperature‐induced changes in hydraulic conductivity, and
 variable stream stage, and was quantified using the MAD of detrended
 fluxes (daily mean subtracted). Daily variability (MADD), calculated as
 the MAD of daily median fluxes for a given year, exceeded sub‐daily
 variability, and was influenced by strong seasonality at some sites. For
 individual sites and water years, the ratio of MADS‐D to MADD ranged from
 0.03 to 0.70, with an average of 0.25. Annual median fluxes at each site
 varied across years, but typically remained consistent in order of
 magnitude and direction. Results reveal a strong linear correlation
 between the daily variability and the median annual flux at individual
 sites. Within a year, summer months characterized by stronger losing
 conditions showed greater overall variability. 1D numerical heat and flow
 modelling was performed to calibrate hydraulic parameters and to
 investigate temperature‐related controls for sub‐daily variations. We
 discuss implications of documented temporal variability for analyses of
 hyporheic exchange and groundwater recharge. Results provide a basis for
 quantifying temporal variations in streambed fluxes and highlight the
 extent to which fluxes vary over multiple timescales.
description: This dataset includes 10-minute timeseries (28-SEP-2018 to
 28-SEP-2021) of temperature, groundwater level, vertical hydraulic
 gradient (VHG), Darcy flux (q), temperature dependent hydraulic
 conductivity (K), barometric pressure, and related metadata for a nested
 streambed piezometer network located on East Plum and Cherry Creeks in
 Colorado, USA. 
description: # **Paper: Multiple timescales of streambed flux variability in two
 perennial mountain-front streams** Authors: Kristen Cognac, Michael
 Ronayne ### Description: This README file describes the data package
 accompanying the above publication. ### Files: * Data folder: Includes
 seven text files ('.txt') containing comma-separated timeseries
 datasets. * Files
 'CCA.txt','CCB.txt','PCB.txt','PCC.txt','PCDS.txt', and 'PCMU.txt' correspond to piezometer nest locations with columns: * Date\_time: date and time stamp of data * Shal\_Temp\_C: shallow piezometer temperature in degrees Celsius * Deep\_Temp\_C: deep piezometer temperature in degrees Celsius * Shal\_Head\_m: shallow piezometer water level relative to streambed in meters * Deep\_Head\_m: deep piezometer water level relative to streambed in meters * SDgrad: vertical hydraulic gradient between shallow and deep piezometer * K: time-varying hydraulic conductivity corrected for temperature in meters per day * The file 'Baro.txt' contains barometric pressure timeseries with columns: * Date\_time: date and time stamp of data * BaroT: air temperature in degrees Celsius * Corr\_Baro\_m: barometric pressure as meters of water. * Script: Example MATLAB script 'Process\_PZ\_Dat.m' to import datasets and generate plots and statistics from associated manuscript. Created with MATLAB version: '9.13.0.2105380 (R2022b) Update 2'. * Metadata: Comma-separated file containing location and depth metadata for piezometers with columns: * Site\_Name: name of piezometer nest location * Latitude: latitude coordinate of piezometer nest * Longtidue: longitude coordinate of piezometer nest * Shal\_Depth: midpoint of shallow piezometer slotted interval as depth into streambed in meters * Deep\_Depth: midpoint of deep piezometer slotted interval as depth into streambed in meters * Elevation: elevation of streambed at piezomter nest to the nearest meter above mean sea level * Distance: For PC sites, distance from mountain front. For CC sites, distance of longest path from drainage divide