Why boil...
Since I am in the tap water business, I'll offer some info if you like...The problem with turbidity (dirt) in the water is that it makes the chlorine less effective. So that really means that if there are some bugs in the water they may not be killed. Hence boiling will kill them. Now the big question is how many bugs are in the water??? Since this was a large rain event then there is a good possibility of animal droppings etc. being washed into the reservior. If you think of how large a body this is, then you can determine how big a risk this is.
Think also of the risk you take using a public washroom and grabbing the door handle - many do not wash thier hands ya know, compare that with the drinking water, or think about a BBBJ or DATY risk factor or just general body licking --- just remember that us officials have to cover our butt in this business. If 100 people got sick out of the millions, its a relatively low number, BUT the media and the public out cry is just unreal, then the lawyers show up. But how many people on an average night get injured in car accidents in the lower mainland - every night.....