The water from Thomas Spring joins an unnamed tributary that flows northward until it joins Halls Creek. Along the way, the tributary receives water from Glenn Spring, another of the five springs inhabited by the Watercress Darter. Glenn Spring is on private land. Halls Creek joins Valley Creek to the north of I-20/59. Valley Creek joins the Black Warrior River on the boundary line between Jefferson and Walker counties.
The pond at the end of the refuge trail is not the spring’s pool. It is a reservoir created to provide additional habitat for the darter. Water for this pool comes from Thomas Spring, which is through the forest to the southeast of the boardwalk.
Springs such as Thomas and Glenn were once widely abundant in Jones Valley. While a few still exist, many others have been filled in or rerouted as urbanization took hold. These springs provided reliable, clean drinking water for Birmingham’s earliest settlers. Those that survive enrich our landscape and – in a few cases – provide habitats for some of Alabama’s unique species.