WSP11570

• File Number: 8111.807
• Description: Arkansas River Compact Administration - Stream Gage Evaluation
• Basin: Arkansas
• Date: 1/1/1980
• Author: USGS
• Title: Cost-Effective Stream Gaging Strategies for the Lower Colorado River
• Water Supply Pro - Doc Type: Publication

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NR routes is represented by a row of the table and each of the Me stations is

represented by a column.

The zero-one matrix, w.., defines the routes in terms
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of the stations that comprise it. A value of one in row i and column j designates

that station j will be visited on route i; a value of zero indicates that it

will not.

The unit travel costs, S., are the per-trip costs of the hydrographer's
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travel time and any related per diem and the operation, maintenance, and rental

costs of vehicles.

The sum of the products of S. and N. for all i is the
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total travel cost associated with the set of decisions, ~.

The unit-visit cost, a., is comprised of the average service and
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maintenance costs incurred on a visit to the station plus the average

cost of making a discharge measurement. The set of constraints of
minimum visits is denoted by the row, A.. The row, N., specifies the number
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of visits made to each station. N. is the sum of the products of w. . and N.
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for all i and must equal or exceed A. for all j, if N is a feasible decision.
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The total cost expended at the stations is equal to the sum of the

products of a. and N. for all j. The cost of record computation,
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documentation, and publication is assumed to be influenced negligibly by the

number of visits to the station and is included along with overhead in

the fixed cost of operating the network.

The total cost of the network

equals the sum of the travel costs, the at-site costs, and the fixed cost

and must be less than or equal to the available budget.

The total uncertainty or variance of estimates of annual discharges

at the Me stations is determined by summing each of the uncertainty

functions, f., evaluated at the value of N. from the row above it.
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As stated above, classical techniques for optimization are not adequate

for the problem at hand. Therefore, to solve the problem an iterative

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