Soil moisture forecasting for agricultural applications using HGSRT hydrologic simulation platform

Overview

Aquanty is exploring the extension of its HydroGeoSphere Real-Time (HGSRT) simulation platform to include soil moisture forecasting for field-scale agricultural applications. HGSRT is a physics-based hydrologic forecasting platform that has already demonstrated skill in predicting river flows and groundwater levels for 3 to 5 day future intervals. Because the platform fully closes the water balance across rivers, groundwater, and the soil profile, accurate representation of soil moisture is a governing factor in its existing forecasts. This initiative aims to validate whether that same numerical framework can deliver reliable soil moisture predictions that support agricultural decision-making.

The opportunity addresses a significant gap in operational hydrologic forecasting. While soil moisture is a critical variable for agriculture, current forecasting tools rarely integrate it with surface water and groundwater predictions in a single platform. Extending HGSRT's capabilities would provide farmers, watershed managers, and agricultural planners with a unified view of soil moisture conditions alongside water availability forecasts.

Technical specifications

Platform and approach:

• HGSRT is a real-time hydrologic simulation platform that closes the complete water balance, accounting for changes in storage within rivers, groundwater, and the soil profile
• The platform has been validated for river flow and groundwater level forecasting over a two-year interval in the 4000 sq-km South Nation watershed in Canada
• Current validation testing is underway across 80,000 sq-km of Southern Ontario, with promising results for surface water and groundwater conditions
• HGSRT has been validated for sub-surface tile drain flow forecasting at the highly monitored WEBS research site near Ottawa, Canada

Proposed validation methodology:

• Historic field-based soil moisture monitoring datasets will be obtained for areas where HGSRT is already deployed
• Representative soil moisture monitoring points will be configured into the HGSRT platform
• Historic forecasts will be reproduced using archived weather data
• Forecasted soil moisture levels will be evaluated against field monitoring data using statistical goodness-of-fit metrics
• If systemic biases are identified, soil hydraulic properties will be adjusted and forecasts reassessed

Technology readiness level

The underlying HGSRT platform is at a high technology readiness level, having been validated for river flow, groundwater level, and tile drain flow forecasting across multiple watersheds in Canada. The specific soil moisture forecasting capability is at an earlier stage of development, with validation testing proposed as the next step. The validation procedure leverages existing platform deployments and archived weather data, enabling efficient assessment without requiring new infrastructure. If validation is successful, the soil moisture forecasting capability would extend an already operational platform to serve agricultural users with field-scale predictions.