 The lower reaches of Toby Creek were polluted by coal mining waste in the early 1900s. However, in modern times, no part of the watershed of Toby Creek is considered to be impaired. It has been described as showing "some degraded conditions", but does not rank among the most polluted watersheds in the Middle Susquehanna Subbasin. However, the creek has high levels of nutrients and sodium. There is one combined sewer overflow in the watershed, near the mouth of the creek.
