Watershed Profile: Mill Creek near Lancaster, PA


Watershed Overview
Mill Creek generally flows east to west before it joins the Conestoga River. The Mill Creek Watershed is located entirely within Lancaster County, PA. The monitoring station is located near its confluence with the Conestoga River.
Drainage Characteristics
  • Drainage Area (square miles): 54.65
  • Total Stream Length (miles): 75.80
  • Average Annual Flow at Station (NHD) (cfs): 74.60
  • Population (2010): 32,660
Stream Classifications (Pennsylvania)
Designation Miles
Cold Water Fisheries 7.32
High-Quality Cold Water Fisheries 1.65
Warm Water Fisheries 66.86
Total 75.83
  • Land Use
  • Description Percentage
    Water 0.32
    Developed Open Space 9.51
    Low Urban 8.38
    Medium Urban 4.20
    High Urban 2.45
    Barren 0.12
    Deciduous Forest 6.34
    Coniferous Forest 0.14
    Mixed Forest 2.72
    Shrub Scrub 0.56
    Grassland Herbaceous 0.08
    Pasture/Hay 13.44
    Cropland 51.93
    Wetlands 0.06
Underlying Geology
Rock Type Percentage
Dolomite 61.65
Limestone 26.17
Other 1.53
Quartzite 8.81
Shale 1.85
Map
Recent Results
Sample Time 11/26/2020 3:00:00 PM
Temperature  (C) 11.46
Specific Conductivity  (mS/cm) 0.73
PH 8.21
Turbidity  (NTU+) 3.43
Dissolved Oxygen  (mg/L) 12.77
Dissolved Oxygen (last month of readings)
pH (last month of readings)
Specific Conductivity (last month of readings)
Temperature (last month of readings)
Turbidity (last month of readings)
Natural Gas
  • Natural Gas Pads 0
  • Natural Gas Water Withdrawals 0
Public Water Supply Withdrawals
  • Groundwater 79
  • Surface Water 1
NPDES Discharges
Description Count
Concentrated Animal Feeding Operation 5
Mining/Quarry 0
Stormwater 14
Wastewater Treatment Plant/Sewage Treatment Plant 4
Other 18
Stream Impairments
Source Category Miles
Agriculture Aquatic Life 42.00
Crop Production Aquatic Life 9.40
Grazing in Riparian Zones Aquatic Life 12.20
Industrial Point Source Aquatic Life 0.90
Site Clearance Aquatic Life 0.80
Source Unknown Recreational 72.40