Thanks everyone for the advice/links!

I encourage you to visit:

http://jcwaterfight.com/main/jcmua/

Aside from doing what we can in the short term to protect our properties ourselves, this needs to be taken to a whole other level for long term solutions.

Stop by A1 storage on tenth street and ask them how successful their Bituthene sheets were on their doors. They stapled sheets of Bituthene on all their doors ahead of the flooding, and I know their doors were under around 3 feet of water. I think what they used was Bituthene 4000 membrane - which looks like an easy-to-apply self-adhesive waterproof roll. I've linked the company website, and the 3rd photo in the solar world link shows what the sheets look like.

I don't have a basement, and I didn't get flooded, but the water came close. I plan to order some of this stuff to seal my doors next time. It looks much better than alternatives such as sandbags. It also looks like it would work on any doors, basement openings, etc. If the flooding comes from above ground and isn't seeping in through the walls of your basement, this might work for you.

http://www.na.graceconstruction.com/p ... .cfm?mode=c&id=137&did=11

http://solar.world.org/solar/waterproofing

Thanks, MDM, for the advice.

Does anyone know who you'd hire to consult on something like this - e.g., would you hire an surveyor/engineer to evaluate the street/sidewalk slope, etc? Has anyone done that here? We don't want to piss away another several thousand dollars on a mason doing work or something without getting smarter about how water is flowing in, what's really needed, etc.

From an engineering perspective and seeing some flood walls around properties in the Midwest:

Unless you have some three phased powered monster pump in your basement, you won't keep up with 2 ft of water pouring through the basement door. I would look at installing a 3ft wall (recommend it be reinforced with rebar) and maybe using a concrete mix geared towards holding back water. Either a hydraulic concrete or the kind that uses some fly-ash (the Romans discovered that ash made their concrete much more resistant to water.. the ash fills in all the little spaces in the pour). The wall will also have to extend underground a bit to prevent flood water from undermining it. No clue off the top of my head what that depth should be. I am sure there is some civil engineer out there who knows though.

You can dress up the wall with a stone facade', plants, or whatever.. as long as you leave the water tight core in place.

I would fashion the entrance going down to your basement steps with a groove that would allow a heavy board to be slipped in and weighted down (so it doesn't float back up). That board can easily be removed once the flooding is gone. Yachts use item like these to prevent deck wash from going down the stairs into the hold. I am sure there is a term for the device, but I have no idea what it is.

Anyway.. that's my $0.02 on the subject.

We've invested thousands of dollars in sumps, trenches etc. and they generally work. Nothing, however, can keep up with the river that 5th becomes during heavy rain. I'm thinking we need to stop the flow before it even hits our basement entrance area.

I noticed several houses have 'walls' some even a foot tall at the top of their steps leading to their basement area/lower apt. For those of you who do, have you ever experienced flooding? Does it help? We are just a bit of a loss having now had 2 3-ft+ flooding.