Mean Hypolimnetic Depth
 
Used in predicting hypolimnetic and metalimnetic oxygen depletion rates in stratified reservoirs.
 
 = hypolimnetic volume (hm3) / hypolimnetic surface area (km2)
 
If the Mean Hypolimnetic Depth = 0., segment is assumed to be unstratified and oxygen depletion rates are not calculated. Mean hypolimnetic depth should correspond to late spring or early summer, after onset of stratification.

The PROFILE program (Walker, 1999; Chapter 2 ) can be used to examine thermal profiles and calculate mean hypolimnetic depth. 

Since the empirical models for predicting oxygen depletion rate have been developed using data from near-dam stations, hypolimnetic depths should be specified only for near-dam segments. 

Predictions of depletion rates in upper pool segments are not reliable without calibration to site-specific data.