J. MILLARD TAWES, GOVERNOR                          1279

to a sewerage system shall be liable therefor and the collection thereof
may be delegated by the District to the owner or operator of a con-
nected sewerage system.

(b)  Any such schedule, and any revisions, alterations, or amend-
ments thereof, shall be adopted by resolution of the Commission and
shall be uniformly applicable throughout the sub-district for which
it is adopted. Any such schedule may, however, provide that the
sewer service charge for each property connected both to a water
system and a sewerage system shall be computed at a fixed percentage
of the total water bill for each such property and that for any property
connected to a sewerage system but not to a water system, the sewer
service charge may be fixed on a flat rate basis which may vary de-
pending on the number of occupants of a premises, the type of use or
the number of fixtures on any such premises connected to the sewerage
system, or such sewer service charge may be calculated in accordance
with the volume of sewage discharged by any premises as measured
by a meter installed on the sewer connection by, and at the expense
of, the Commission. In any such schedule, the Commission may also
provide equitable surcharges for industrial or chemical wastes dis-
charged into a sewerage system which require special treatment
different from the normal process of digesting organic wastes and
the Commission may also include in any such schedule special rates
for charitable, religious or public institutions in the same manner and
to the same extent as provided in Section 544 of this sub-title for
water service charges. All sewer service charges shall be added to,
and form a part of, the water bills of all properties connected both
to a water system and to a sewerage system, and said sewer service
charges shall be collectible and enforceable in the same manner and
to the same extent as is provided for said water service charges by
Section 544 of this sub-title. Separate bills for sewer service charges
shall be sent separately to all properties connected to a sewerage
system ONLY and the provisions of Section 544 of this sub-title with
respect to the collection and enforcement of water bills shall apply
to said separate bills for sewer service charges except for the pro-
vision with respect to the discontinuance of service in the event of
delinquency.

(c)  All revenues collected by the Commission from sewer service
charges shall be applied, first, to payment of the cost of operating,
maintaining and repairing the sewerage systems of the District in
such sub-districts from which such revenues are obtained. Secondly,
such revenues shall be applied to payment of the cost of operating,
maintaining and repairing any surface water drainage system in a
sub-district for which no ad valorem tax is provided pursuant to this
sub-title, if such surface water drainage system was constructed by
the District in conjunction with the sewerage system for which such
charges are made or for the purpose of separating the sanitary and
surface sewage and drainage so as to relieve the burden on any such
sewerage system. Said revenues may also be expended for a pro-
portionate share of the cost of operating overhead of said District
and the Commission may further reserve and set aside from said
revenues appropriate depreciation reserves for expenditure or ON re-
placements of wornout equipment or facilities forming part of any
such system or related storm water drainage systems, or for im-
provements thereto. After making appropriate provision for the fore-
going expenditures and reserves, the Commission shall apply such