Questions regarding PHABSIM analyses
- District’s MFL team have used PHABSIM for other MFLs. The use of PHABSIM as a best available aquatic habitat assessment tool has also been accepted by previous peer reviews. Was the PHABSIM application for the Pithlachascotee River done in standardized approach, comparable to how it has been applied to other river systems in the District? Were there any significant variations from the District’s standard PHABSIM data collection, or analysis?
- Have previous MFL peer reviews assessed the suite of embedded PHASIM tools (i.e., hydraulic model, TSLIB, etc.) ? If so, have the models been deemed appropriate for use with rivers in the District? Were any cautions or limitations highlighted by other peer reviewers?
- Was the PHABSIM data collection and analysis done by District staff?
- Overall results of the PHABSIM analyses are summarized in Table 5-1 (page 92) of the report. It is not clear how the summary in Table 5-1 are derived from the plots in Appendix 5B. Please provide a step wise description.
- Table 5-1 indicated and the supporting text in report say that the PHABSIM analyses were done separately for flow regime Blocks 1 & 2. I did not see comparative plots for Blocks I and 2 by taxon in Appendix 5. How can I verify the summary values for Blocks 1 & 2 in Table 5-1?
- For the critical values in Table 5-1---can the threshold be exceeded by a single month’s excursion. Please explain.
- I understand that maximum allowable percent flow reductions presented in Table 5-1 were calculated using mean monthly value for river flows for baseline versus incremental percent flow reductions. Mean monthly flow values were in turn used to estimate mean monthly habitat values, and percent change from baseline. The explanation for this analysis in Appendix 4C was unclear. Please provide a step-wise description as to how the final maximum allowable flow reductions values in Table 5-1 were calculated.