She has been watching the sparrows for days, first quietly as the female gathered twigs, dry grass, and bison hair; then more openly, strategically entering the sparrows' territory, raising a flurry of chirps from the pair, louder and more frantic the closer she came to their nest. The intruder is a drab grey-brown bird, without the intricate streaks and stripes of the sparrows, matching the dust raised by the bison herd that grazes the prairie around them.

If you’ve ever driven past a construction site and noticed black silt fences, straw wattles snaking along slopes, or muddy water pooling near storm drains, you’ve seen erosion and sediment control — or the lack of it — in action. What you might not have noticed is whether a CPESC was on the job. Spoiler: it matters a lot.

Wetlands are not always “wet” when you happen to visit them. They are dynamic systems shaped by snowmelt, rainfall, groundwater, soil characteristics, vegetation, and site position. Some hold water for long periods, while others only show themselves clearly for a short window each year.

That is why timing is a consideration during any site visit. In May, a low spot in a project area may be full of water. By August, that same area may be dry enough to walk across in regular boots. Same site, different season, very different evidence. A wetland assessment is not just about whether there is water on site that day. It is about understanding how water moves through the area over time.