[Data may not add to totals because of independent rounding. Mgal/d == million gallons per day; gal/d = gallons per day; < = less than. Source: Maryland- Herring (1983), Sotley, Chase, and Mann, (1983); District of Columbia-Solley, Chase, and Mann (1983)]

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          POPULATION SERVED BY SURFACE WATER, 1980
                                                                 Md    D.C.
Number (thousands)........................................... 3,040    638
Percentage of total population...............................    72    100
From public water-supply systems:
  Number (thousands)......................................... 3,040    638
  Percentage of total population.............................    72    100
From rural self-supplied systems:
  Number (thousands).........................................     0      0
  Percentage of total population.............................     0      0
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                        OFFSTREAM USE, 1980
                        FRESHWATER WITHDRAWALS
Surface water and ground water, total (Mgal/d)............... 1,400    340
Surface water only (Mgal/d)..................................   970    340
  Percentage of total........................................    70    100
  Percentage of total excluding withdrawals
       for thermoelectric power..............................    58    100
                            Category of use
Public-supply withdrawals:
  Surface water (Mgal/d).....................................   440    210
  Percentage of total surface water..........................    45     62
  Percentage of total public supply..........................    90    100
Per capita (gal/d)...........................................   145    329
Rural-supply withdrawals:
  Domestic:
    Surface water (Mgal/d)...................................     0      0
    Percentage of total surface water........................     0      0
    Percentage of total rural domestic.......................     0      0
    Per capita (gal/d).......................................     0      0
  Livestock:
    Surface water (Mgal/d)...................................     0.5    0
    Percentage of total surface water........................    <0.1    0
    Percentage of total livestock............................     5      0
  Industrial self-supplied withdrawals:
    Surface water (Mgal/d)...................................   520    130
    Percentage of total surface water........................    53     38
  Percentage of total industrial self-supplied:
    Including withdrawals for thermoelectric power...........    93    100
    Excluding withdrawals for thermoelectric power...........    80     43
  Irrigation withdrawals:
    Surface water (Mgal/d)...................................     9.4    0
    Percentage of total surface water........................     1      0
    Percentage of total irrigation...........................    47      0
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                         INSTREAM USE, 1980
Hydroelectric power (Mgal/d)................................. 15,000     8.0
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