If a State makes, from its water pollution revolving fund, a loan which will finance the cost of facility planning and the preparation of plans, specifications, and estimates for construction of publicly owned treatment works, the State shall ensure that if the recipient of such loan receives a grant under section
1281
(g) of this title for construction of such treatment works and an allowance under section
1281
(l)(1) of this title for non-Federal funds expended for such planning and preparation, such recipient will promptly repay such loan to the extent of such allowance.