For this option, we would install permanent height markers where the four corners of reservoir 607 stood. We would then demarcate the former border of the reservoir with a concrete inlay or similar.
During our exploration, we discovered that the boundary of the new tanks would overlap with the concrete border. The new tanks will also be slightly taller than the original reservoir, so the height posts may not have the desired impact. It is for these reasons that we do not recommend this option.