Geologist Donna Falconer claims Meridian's explanation doesn't stack up and believes they are looking for damage in the canals.
"You only have to drive along the canals and see all the heavy earthmoving gear ... They are looking for leaks down in the zone where all this seismic activity has been."
I'll have to go with Crazy Donna* here! What are they doing with this? Most likely they have a significant increase in water leakage, as measured at the gate. So, you've got to drain it and look, in the middle of night, when nobody sees you! Ha, Ha!
*term of endearment.