Sewage pollution undoubtedly impacts the estuary and river. However, despite this pollution, the salt marsh remains one of the best examples of a healthy, functioning marsh in southern California. The Tijuana Estuary is an intact system with extensive marsh vegetation and is open to tidal flushing (which increases nutrient and oxygen flow). This helps alleviate the pollution problem.
The salt marsh is a very resilient ecosystem (it actually filters out much of the sewage) and remains fairly stable. In fact, excessive fresh water released on both sides of the border can be more problematic, as it throws the estuary’s ecosystem out of balance. Sediment and trash represent a serious threat as they can smother and damage wetland habitat.