The governing body of the watershed improvement district shall, if necessary to pay the interest on the indebtedness or bonds or to amortize such indebtedness or bonds, levy an annual tax or service charge in the manner prescribed by § 10.1-626 on all the real estate in the watershed improvement district subject to local taxation, to satisfy such obligations. This tax, irrespective of any approvals required pursuant to § 10.1-614, shall be sufficient to pay interest and to amortize such indebtedness or bonds at the times required.
Va. Code § 10.1-631