Helping protect the health of wetland complexes from the impacts of infrastructure projects with WetlandWATCH

Manitoba Flood Diversion - Digital Services

The provincial government in Manitoba dug a flood diversion trench between two large bodies of water, which cut through the center of a wetland area. While some parts of the wetland were divided from one another, others received an influx of water from the flood diversion process. Both too little and too much water impact wetland hydrology and substrate water content.

To satisfy the requirements of an environmental assessment, Manitoba Transportation and Infrastructure reached out to our Digital Services team to help them predict how the functionality of the wetland might change over time.

Using our digital service WetlandWATCH, we monitored the effects of the trench’s construction on the wetland hydrology through change detection analysis. WetlandWATCH draws on information from synthetic-aperture radar (SAR) imagery. Comparing wetland data prior to construction with wetland data after, we found that the trench demonstrated a drying effect, which meant less water was available within the substrate. However, the parts of the wetlands being inundated with flood waters showed an increase in saturation in their substrate.

To the naked eye, the surface vegetation of the impacted wetlands appeared unaffected in the short term, but the drier wetlands could eventually cease to exist, and the flood wetlands could become open waterbodies. With WetlandWATCH, Manitoba Transportation and Infrastructure was able to estimate impacts of the trench to complete and submit their environmental assessment.