Table 11. Template for an environmental flow monitoring program designed for the Lesotho Highlands Water Project (modified from LHDA 2003). The zones include the aquatic, lower wetbank, upper wetbank, lower dynamic, and tree/shrub zones (Metsi Consultants 2000a).


Indicator   Category A   Category B   Category C   Category D   Category E/F
     Pristine   Near natural   Moderately
  modified
  Significantly
  modified
     Severely
   modified
Geomorphology
/hydraulics
    Instream
    habitat     diversity
  Full natural diversity   5–15% loss   15–40% loss   40–70% loss   > 70% loss
    Pool depth   Natural   5–15% loss   15–40% loss   40–70% loss   > 70% loss
    Bank area     eroded or     collapsed   < 5%   5–10%   10–20%   20–40%       > 40%
Water quality
    Change in     mean monthly     temperature   Natural     < 3°     < 4°     < 5°       < 6°
    Change in     annual pH     range   Natural   < 0.5 pH units   < 1.0 pH units   < 1.5 pH units   < 2 pH units
    Total Rapid     Biological     Assessment     (SASS) Score   Unknown   > 95   94–70   69–45   < 45
Vegetation
    Zone     definition   All present and distinct   All present and distinct   Loss of < 2 zones and/or zone definition less distinct   Loss of < 3 zones and/or zone definition indistinct   No definition
    Species     composition     of riparian     vegetation   Full complement   Change in ratios of indigenous species   Dominated by hardy indigenous species and/or exotic species   Dominated by exotics and/or weedy indigenous species   Dominated by one or two species, often > 80% exotics OR no plants
    Growth forms   Full array of growth forms   5–10% reduction   11–25% reduction   26–50% reduction     > 50% reduction
Fish
    Community     composition   Full complement of native species in natural proportions; no exotic species   Full complement of native species, plus very low numbers of exotic species   Noticeable shifts in structure of native fish community, moderate numbers of exotic species   Very few native fish species and/or exotic
fish dominate
  Very few fish species, dominated by exotic species