The governments of Alberta, Saskatchewan, Manitoba and Canada entered into a Master Agreement on Apportionment, for sharing the waters of eastward flowing interprovincial streams. The agreement also recognizes the problem of water quality and groundwater matters, and reconstituted the Prairie Provinces Water Board to administer the agreement and provide a forum to resolve and report on interprovincial water issues.

Five schedules are part of the master agreement.

  • Schedule A
    The Apportionment Agreement between Alberta and Saskatchewan.
  • Schedule B
    The Apportionment Agreement between Saskatchewan and Manitoba.
  • Schedule C
    The Prairie Provinces Water Board Agreement describing the composition, functions and duties of the Board.
  • Schedule D
    A listing of Orders-in-Council for allocations of interprovincial waters made before 1969.
  • Schedule E
    A Water Quality Agreement. This Schedule became part of the Master Agreement in 1992.

The sharing of waters of eastward flowing streams between Alberta and Saskatchewan is governed by Schedule A of the Master Agreement On Apportionment including:

  • Cold River
  • Beaver River
  • North Saskatchewan River
  • Battle River
  • Eyehill Creek
  • South Saskatchewan River
  • Boxelder Creek
  • Battle Creek
  • Middle Creek
  • Lodge Creek

The general principle of the agreement is outlined in Paragraph 3, Schedule A, which states:

"Alberta shall permit a quantity of water equal to one-half the natural flow of each watercourse to flow into the Province of Saskatchewan, and the actual flow into the Province of Saskatchewan shall be adjusted from time to time on an equitable basis during each calendar year, but this shall not restrict or prohibit Alberta from diverting or consuming any quantity of water from any watercourse provided that Alberta diverts water to which it is entitled of comparable quality from other streams or rivers into such watercourse to meet its commitments to Saskatchewan with respect to each watercourse."

And by paragraph 2b which states:

"For the purpose of this agreement, the said natural flow shall be determined at a point as near as reasonably may be to the said common boundary."

The above principle applies to streams flowing eastward from Alberta to Saskatchewan, but several special provisions have been included in the agreement on sharing the waters of the South Saskatchewan River and of Battle, Middle and Lodge Creek.

Apportionment monitoring is carried out for the South Saskatchewan River, Battle Creek, Middle Creek and Lodge Creek and Cold River, but not for the Beaver River, North Saskatchewan River, Battle River, Boxelder Creek and Eyehill Creek, as Alberta's consumptive water use in these streams is an insignificant portion of the natural flow.

Battle, Middle and Lodge Creek

These creeks originate in the Cypress Hills of southeastern Alberta, flow in a southeasterly direction into Saskatchewan and across the international boundary into Montana, emptying into the Milk River.

The streams are tributaries of the Milk, governed by both the Boundary Waters Treaty (1909) that requires Canada to pass half the flow to Montana, and by Schedule A of the 1969 Master Agreement on Apportionment between Alberta and Saskatchewan. Recognizing Canada's obligations to the U.S. on these streams, the 1969 master agreement says that three-quarters of the annual flow will pass the interprovincial boundary from Alberta to Saskatchewan.

The balancing period for the creeks is the calendar year. Calculations on apportionment are carried out quarterly (more frequently if required) by the Prairie Provinces Water Board. Surplus deliveries by the upstream jurisdiction cannot be banked or used to offset shortfalls in subsequent years.

South Saskatchewan River

The general principle of the Master Agreement on Apportionment says that Alberta will allow half the natural flow of each of its rivers (minus diversions to the United States) to flow into Saskatchewan.

The South Saskatchewan River, however, is subject to some added conditions:

  • The waters of the South Saskatchewan and Red Deer rivers may be treated as one, for apportionment purposes.
  • When natural flow (minus United States diversions) of the South Saskatchewan River at the boundary is greater than 3,000 cubic feet per second, the minimum actual flow will be 1,500 cubic feet per second.
  • When natural flow at the boundary is less than 3,000 cubic feet per second, the minimum actual flow will be half of this.


Connect with the Transboundary Waters Secretariat:
Email: [email protected]

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