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Mill Creek and TributariesSelect Location: Select from drop-down list or use clickable map below.
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Location 31 is where a small private road crosses the south tributary of Mill Creek into Mill Creek Estates. There is a single-lane wooden bridge crossing the creek and lawn in the developed area. Further upstream, the tree coverage increase in the riparian zone. The south tributary of Mill creek is approximately 3 to 4.5 m (10 to 15 feet) wide, the channel banks are nearly vertical on the left bank and gently sloping on the right bank. The substrate is gravel.
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Locations 32 and 33 are where the north tributary of Mill Creek approaches the confluence with the south tributary. The team walked from a small road toward Old Elk Neck Road and examined the main stem of Mill Creek on both sides of the culvert passing under the Old Elk Neck Road. There is an extensive riparian zone on the lower reaches of Mill Creek and on both tributaries when looking upstream. There was some trash and debris in the riparian zone, which was uncharacteristic of other areas in the watershed. The creek is on the order of 4.5 to 6 m (15 to 20 feet) wide downstream of the bridge and has gently sloping banks on both sides. The creek flows under the road in three short spans. There is no flow restriction. The substrate here is finer (sand) than at upstream locations.
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Locations 43 and 44 are where the north tributary of Mill Creek passes under Route 7. The land on the south side of Route 7 is manicured and passes through a road maintenance facility in a ditch, with young phragmites beginning to grow on the bank. The water course was approximately 0.5 to 1 m (2 to 3 feet) wide and a few inches deep at the time of the visit. The fish habitat value is very poor. The channel upstream of Route 7 is in much better condition, with sand and gravel in the bed and trees overhanging the banks. The depth of the water was only a few inches and provided little to no fish habitat value, especially considering the downstream condition of the creek. The creek flows through twin 40-inch diameter corrugated steel pipes under the road, although only one pipe carried flow during our visit.
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Locations 45 and 46 are where the south tributary of Mill Creek crosses under Route 7. Mill Creek varies between 2 and 4.5 m (10 and 15 feet) in width at this location. Upstream of the road, the substrate is sand with some angular cobbles. There are trees and shrubs overhanging the water course and there was no indication of erosion on the shallow banks. Downstream of the road, the channel bed is sand and small gravel with some large angular rocks up to 24 inches across. The water had an orange, iron-stained tint. The creek passes under the road through three semicircular arches that do not obstruct fish passage. The owner of a nearby property reported that there were no anadromous fish in this reach of Mill Creek. However, he reported having observed small resident fish of several different species including sun fish, chain pickerel, "small brown fish", and what he described as lamprey eels. In his opinion, beaver dams, further downstream on the creek, were an impediment to fish migration.
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Location 47 is where an unpaved track leading to the Maryland Sand Gravel and Stone Superfund site, crosses over the south tributary of Mill Creek. The creek water is stained a bright orange color at this location and phragmites are abundant in and adjacent to the creek. The creek is only 1 to 2 m (3 to 5 feet) wide and a few inches deep, without discernable banks. This area may be poor fish habitat due to degraded water quality, lack of suitable habitat, and insufficient flow.
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Locations 48 and 49 are where US 40 crosses over the south tributary of Mill Creek. The creek is relatively straight and slow-moving upstream of the highway, and passes under the road through a rectangular culvert. Water in the creek was iron-stained and algae was observed. The creek passes through a forested area that provides a full riparian buffer. The creek bed is sand and gravel. Downstream of the highway, the apron of the culvert drops approximately one foot to a pool. This drop could be a fish passage obstruction, although beaver dams downstream (as described at locations 45 and 46) may preclude migratory fish from this location. A downed tree straddled the creek a few feet downstream of the culvert apron. The creek banks are 0.5 to 1 m (2 to 3 feet) high below the highway, which may indicate downcutting. The riparian vegetation is a good mix of trees and shrubs. There was evidence of repairs to the highway embankment on the left downstream bank, which suggests that highway runoff overwhelms the capacity of the stormwater system or that the discharge in Mill Creek is periodically too high for the culvert.
