ACCESSING THE IMPACT OF SURFACE MINING IN THE COLLINS FORK WATERSHED USING THE ROSGEN LEVEL-1 STREAM CLASSIFICATION, SOUTHEASTERN OHIO

Surface mining and reclamation practices can have a major impact on the hydrology of watersheds. We accessed the impact of surfacing mining on the Collins Fork watershed, which is a 14-digit watershed in southeastern Ohio. The watershed covers 59 square kilometers and was extensively mined for the Meigs Creek coal (Monongahela Group). The Pennsylvanian Monongahela Group underlies approximately 76 percent of the watershed. About 60 percent of the watershed was surface mined mainly during the 1970s through the 1980s but some mining occurred in the watershed before the 1960s. During the reclamation process approximately 100 lakes were constructed in the watershed.

We applied the Rosgen Level-1 stream classification to the watershed using 1961 topographic maps to determine the pre-mining stream distribution. In 1961, the watershed contained 6.6 km of streams with 6 % A-type, 48 % B-type, and 46 % C-type streams. We compared the original stream distribution in the Collins Fork watershed with a similar watershed that experienced no surface mining located 12 km to the northwest. The Salt Creek watershed covers 128 square kilometers and approximately 85 % of the watershed is underlain by the Pennsylvanian Conemaugh Group. The watershed contains 18.5 km of streams with 5 % A-type, 33 % B-type, and 62 % C-type streams. While similar, the Salt Creek watershed appears to have a slightly more mature drainage system.

Surface mining affected approximately 3 km of streams in the Collins Fork watershed. We applied the Rosgen classification to the current streams in the watershed using a combination of aerial photographs and field work. Today, the watershed contains only 4.3 km of streams with 7% A-type, 37% B-type and 56 % C-type streams. The biggest change occurred to the B-type streams which decreased by 11 %. The majority of B-type streams were located in the area that was mined. Most but not all of the C-type streams are located in the underlying Conemaugh Group which was not mined in the watershed. Today about 80% of the streams in the Collins Fork watershed are underlain by the Conemaugh Group.