JDMA offers a wide range of hydrometric analyses and terrain analysis services (remote sensing, GIS, field mapping and sampling and geospatial modelling) to interpret and evaluate surficial hydrology. Among various applications, JDMA’s expertise in using terrain analysis for hydrological and watershed modelling has been used to evaluate drainage basins for hydroelectrical potential, to characterize surficial water resources and linkages to shallow groundwater, and to evaluate historical changes in landscapes and water levels.

JDMA has undertaken hydrometric analyses to assist in streamflow and watershed characterization, for flood frequency analysis (to determine the magnitude and frequency of flooding events), for assessment of erosion and bank stability issues, and for application of analytical models. We use an integrated terrain analysis approach to generate watershed models and analyse surficial water flow. Historical airphotos and satellite imagery in conjunction with DEM, hydrometric and meteorological gauge data are used to evaluate historical changes and assess possible future trends. A GIS-based model has been developed to identify potential hydroelectric sites based on digital elevation models of drainage basins, gauge data and stream gradients. Regional models have been applied province-wide and detailed models at specific sites.

Water control projects on agricultural land require delineation of often subtle drainage pathways on low-relief farmland and assessment of areas that may become flooded following the construction of small dams, dykes or other water control structures. JDMA is proficient at acquiring data and imagery required for project planning and preparing permits for regulatory approval.

We have undertaken many studies to describe historical changes to shoreline position and channel morphology, based on comparison of multiple sets of historical imagery and our knowledge of fluvial and lacustrine morphology processes. We have undertaken assignments to characterize morphological processes and conditions on rivers, either to define baseline (pre-Project) conditions or to assess the effects that a project, such as a dam or dikes, has had on sediment transport and erosion processes in a waterway.

JDMA has conducted a morphological study of the Assiniboine River from Portage la Prairie to Winnipeg using multiple sets of historical air photos and high-resolution satellite imagery  and we carried out regional cumulative effects study of lakes and riverine sections covering nearly 27,000 km of shoreline along the Nelson, Churchill, Rat and Burntwood rivers using Landsat imagery and historical air photos to evaluate the regional cumulative effects of hydroelectric development on erosion. We have also characterized baseline erosional conditions on the lower Nelson River for the Conawapa Environmental Impact Assessment studies, and were responsible for drafting the River Morphology chapter for the project’s Environmental Impact Statement. In another project, a UAV was used to collect topographic data to supplement an assessment of historical shoreline erosion on a reservoir in southern Saskatchewan and to recommend ways of optimizing shoreline protection efforts.

Our professional staff are experienced in investigating sedimentation rates, background environmental conditions, paleoenvironmental and historical change, and processes of bank erosion, sediment transport and deposition in lakes and reservoirs. To do this, we use a modified piston corer or other coring devices to extract fine-grained sediment cores. Initial core descriptions are supplemented with analytical analyses that include grain-size, mineralogy, organic carbon, pollen and diatoms. Radioisotope and radiocarbon analyses are used to determine sedimentation rates and to establish a chronology of environmental change in lakes and reservoirs. For these projects, we often collaborate with a diverse group of experienced researchers for the collection and analyses of sediment cores.

JDMA has considerable experience studying morphological changes along rivers and lakes throughout Canada. Sixty years of research and consulting projects have given JDMA a proven expertise in evaluating, assessing, and modelling shore erosion processes in natural and man-made lakes and reservoirs throughout western and northern Canada. This expertise includes pre-construction shoreline evaluation and erosion prediction modelling on proposed hydroelectric reservoirs. JDMA has developed a proprietary GIS-based shore erosion model to predict wave erosion in lakes and reservoirs.

The model predicts volume of eroded material and bank recession rates and distances over time. The model has been successfully applied on studies that have ranged in scale from detailed, site-specific analysis of individual shoreline properties through to regional studies involving hundreds of kilometres of lake and reservoir shoreline. It has been successfully applied in Environmental Impact Assessments, such as those completed for the Wuskwatim, Keeyask, and Conawapa projects in northern Manitoba and the Site C project in British Colombia.