1412 LAWS OF MARYLAND.

(e) Drainage System: All the agencies, methods, appliances
or operations, natural or artificial, singly or combined, that
enter into the collection, transportation and final disposition of
storm, surface or underground water.

(f) Drainage District: All the territory forming the water
shed of a particular stream.

(g) Sewerage or Drainage Areas: Sub-division of Sewer-
age or drainage districts made necessary by topographic or
economic conditions.

(h) Public Nuisance: Any matter, whether'solid, liquid
or gaseous, which of itself is injurious to health or which may
become so, on contact with other substances, whether the latter
may be in themselves harmful or not, further, any matter
which, though not demonstrably poisonous, is offensive to the
senses or which on being allowed to run into a stream will
render the water therein unfit for such purposes as it was used,
before pollution. Also such disposition of any matter, that it
may, while in condition above described, approach within effec-
tive distance of any distance of any dwelling or occupied land
shall be held a public nuisance.

592-E. And be it further enacted, That upon the passage
of this Act, the said Commission shall cause to be shown on a
map of said Prince George's County the various drainage dis-
tricts therein, as shown by the topography in the different parts
of said county. It may thereupon determine which of the dis-
tricts or parts thereof is in most immediate need of sewerage or
drainage facilities, and proceed to have accurate surveys of said
districts made and maps prepared, showing the outlines thereof,
and the various sewerage and drainage areas therein, together
with such topographic detail as will be necessary for the proper
design of sewerage or drainage systems or parts thereof.

Upon these maps shall be projected a proposed plan of main
sewerage and drainage for each district and the various sewer-
age areas therein and they shall constitute and be designated,
on the approval of the State Board of Health, to which dupli-
cate copies shall be sent proposed main sewerage and drain-
age plants for the several districts represented.

529-F. And be it further enacted, That when, after thorough
investigation of the sanitary conditions in any district or area,
the said Commission is convinced that the public health and
welfare demand that all or a portion of the proposed main