(a) Eligible water quality projects which have received advances for planning and design pursuant to subsection (b) of § 22a-439 or § 22a-443 shall be eligible for project grants and loans under this program. No interest shall be charged on a grant advance prior to the time it is converted to a project grant and loan.

(b) Contractual obligations of the state to municipalities for grant assistance commitments made prior to July 1, 1986, shall be funded pursuant to sections 22a-439 to 22a-443, inclusive.