Just allow the solids to settle and sip the water off the top. Make certain you shut off the electrical power or propane gas to your water heater just before draining or it will be ruined! Crack an uppermost faucet and open up a lower hose pipe bib or spout to drain a handful of quarts of water out of your home’s piping.
Make use of water filters and treatment chemicals. I know from prior experience that almost all anyone will drink from awful, scummiest water after having gone without any water for more than a day in harsh heat! If you need to leave your property, carrying a personal supply of water on your back would certainly be extremely tough (at a quart per person daily, a household of 5 might ingest 100 lbs of water in 4 days).
Flood waters are generally very contaminated with farm waste, human sewage, and industrial chemicals, so I highly advise that you purchase a bacteriological back-country-type water filter system that has a carbon center to also remove dangerous chemicals, unpleasant tastes, and stenches. You can chemically manage surface water with household tincture of iodine (5 drops per gallon) and pure chlorine bleach ( six drops per quart) and allowing water to stand for twenty mins.
I produce these items for a lifestyle, so I know what I am speaking about. Boiling for merely 1 min will kill all water-borne living things, but will do nothing to get rid of harmful chemicals, poor tastes, and odors.