How Monitoring Changes from River to Estuary by Linda Green Many stream monitoring programs begin in the upper portion of their watersheds. Eventually they may decide to expand their program downstream to where the river meets the sea.
Estuaries differ from rivers in many regards.
First and foremost, estuaries are subject to tides and the mixing of salt and fresh water. Any successful estuary monitoring program must take into account the stage of tide when scheduling training sessions and sampling times. Tide charts are readily available and should be a standard part of any program coordinator's toolkit. The fact that high tide occurs at different times in different parts of the estuary undeniably complicates scheduling. Estuaries are complex, with a wide variety of environments that are constantly changing.