Gov. Code, § 58106

At the final hearing the supervising authority shall exclude any land which it finds will not be benefited by the proposed project and shall make a specific finding as to each parcel of land with respect to which a written request for exclusion has been presented on the question of whether it will or will not be benefited by the proposed project. In making such finding the supervising authority shall consider present use of such land, reasonable prospective use, topography, the nature of the proposed improvements, and any other pertinent factors. The present use of lands for rights-of-way for railroads, power and communication lines, or other public utility facilities shall be presumed by the supervising authority to be permanent.

The supervising authority may include any land if it finds that the land will be benefited and that its inclusion will be to the interest of the district.

If lands are excluded by the supervising authority pursuant to this section, such lands shall not thereafter be annexed to or included in the district in the absence of a finding, based on substantial evidence, of a change in the circumstances upon which the decision to exclude such lands was based.