construction charges
(d) The term “construction charges” shall mean the amounts of principal obligations payable to the United States under water-right applications, repayment contracts, orders of the Secretary, or other forms of obligation entered into pursuant to the Federal reclamation laws, excepting amounts payable for water rental or power charges, operation and maintenance and other yearly service charges, and excepting also any other operation and maintenance, interest, or other charges which are not covered into the principal sums of the construction accounts of the Bureau of Reclamation.