Plumbing vent pipes and wind draining traps

[twistsol]

Our house is on a bluff above the Mississippi River valley and we frequently get high winds. Today is relatively mild at 25mph. Any time the wind gets to or above 25mph, the water gets sucked out of the traps and toilets on the southwest side of the house. If I remember my physics correctly, the suction is caused by the Bernoulli effect.

Has anyone else encountered this and more importantly, if so, have you found a solution?

[LCHIEN]

Either the wind is blowing into the vent stacks ( like a pitot tube) seems more likely - or else the wind blowing over the ends of the open vent tube is causing a suction.

How about venting or shielding them so that the wind does not enter or blow over the vent stacks.

[Jim Frye]

I've had two similar issues with P-traps. At our old house, cold air would sink down the sewer vent and freeze the water in the traps closest to the vent pipe. I cured that one by putting a 180 degree elbow on the top of the roof vent. This allowed warm house air to rise up the pipe and be trapped by the upside down U pipe. The other issue was due to a P-trap drying out some and a strong wind pulled the remaining water out of the trap causing a real stink from the sewer gas leaking out. The errant trap was a little used bathtub in a spare bathroom. Now I make sure the tub gets a rinse out every time the bathroom gets cleaned to keep the P-trap under the tub full.