A Water Allocation Decision‐Support Model and Tool for Predictions in Ungauged Basins in Northeast British Columbia, Canada

Abstract

Pressures on water resources due to changing climate, increasing demands, and enhanced recognition of environmental flow needs result in the need for hydrology information to support informed water allocation decisions. However, the absence of hydrometric measurements and limited access to hydrology information in many areas impairs water allocation decision-making. This paper describes a water balance-based modeling approach and an innovative web-based decision-support hydrology tool developed to address this need. Using high-resolution climate, vegetation, and watershed data, a simple gridded water balance model, adjusted to account for locational variability, was developed and calibrated against gauged watersheds, to model mean annual runoff. Mean monthly runoff was modeled empirically, using multivariate regression. The modeled annual runoff results are within 20% of the observed mean annual discharge for 78% of the calibration watersheds, with a mean absolute error of 16%. Modeled monthly runoff corresponds well to observed monthly runoff, with a median Nash-Sutcliffe statistic of 0.92 and a median Spearman rank correlation statistic of 0.98. Monthly and annual flow estimates produced from the model are incorporated into a map-and watershed-based decision-support system referred to as the Northeast Water Tool, to provide critical information to decision makers and others on natural water supply, existing allocations, and the needs of the environment.(KEY TERMS: surface water hydrology; computational methods; decision-support systems; Northeast Water Tool.)

Determination of sediment sources following a major wildfire and evaluation of the use of color properties and polycyclic aromatic hydrocarbons (PAHs) as tracers

“…Both Tatsutnai and Nine Mile Creeks empty directly into the Nechako mainstem downstream of the confluence with the Nautley. Table 1 provides more detailed characteristics including drainage area, estimated mean annual discharge, elevation range (Chapman et al 2018 ), land cover (GeoBC 2001 ), and percent burned (BC Forest Analysis and Inventory Branch 2020 ) for each of the tributaries.…”

“… *Estimated by Chapman et al ( 2018 ) a Includes agriculture, herbland, shrubland, and exposed land b Includes mixed, broadleaf, and coniferous forests c Includes only known, maintained roads (GeoBC 2017 ) …”

Modelling river flow in cold and ungauged regions: a review of the purposes, methods, and challenges

“…Recent PUB efforts in Canada using process-based models have focused on small basins, which represent a challenge for practicing hydrologists using empirical models (Spence et al 2013;Chapman et al 2018). At this scale, small changes in topo-geomorphological features and predominant hydrological processes can have large impacts on catchment response.…”

Publishing Environmental Assessment and Management Science: Crossing the Hurdles

“…Assessment scientists develop statistical methods for excluding data or imputing missing data from a large spatial or temporal data set (figure 2 ), but some may reinvent these methods because few scientists (e.g., Srebotnjak et al 2012) think to publish them. A variety of web-based decision support tools are published in the peer reviewed literature by the scientists who maintain them (e.g., Hargrove et al 2009 , Chapman et al 2018 ). Visualization methods can have the novelty required for a peer-reviewed journal and the practicality for aiding decision-makers (Meyer et al 2012 ).…”