In any case, the grant shall not be in excess of three thousand dollars per connection, or, in the case of a source water protection project, for more than twenty percent of the cost per acre for conservation reserve and, except as otherwise provided in this section, no district or system may receive more than one grant for any purpose in any two-year period. Grantees who received or who are receiving funds under the 1993-94 special allocation for flood-impacted communities are not subject to the prohibition against receiving more than one grant during any two-year period for a period ending two years after the final grant allocation for flood-impacted communities is received by that grantee.