Because we don’t live in Venice? Venice does that, and it’s very cool, but it is also has flood issues, concerns about sinking underwater, and was done for geographical and historical reasons starting during the Roman Empire or earlier. Venice was only possible due to its location, a huge shallow lagoon/harbor area where the water naturally provides a good location for that. Trying to artificially get that much water to do that would require huge amounts of effort and resources and disrupt the local water systems. And of course, Venice also has a community with a history of the appropriate skills and cultures that accept the idea.

An alternative would be to build new cities where the water patterns are compatible. Though since ocean levels are expected to rise quite a bit due to our idiotic disruption of the climate of our own planet, it might be wiser to wait for coastal cities to start to submerge naturally, rather than building new ones for the current sea levels.

Given the future sea rises, it might be a good time for people to start planning for systems to adapt coastal cities to Venice-like operations, though.

Pretty sure that would bring up a whole set of new problems.

Because we must drive in parkways, and, covertly, park in driveways. If you have engineering skills enough to stay on the rails, you can drive a choo choo train.

@Zaku I am suggesting that we could have built specialized shallow water ways that were akin to streets. Not using existing water tables. Do you see what I mean? Imagine highways with 3 feet of water the whole way. I guess there would be difficulties in managing water flow… It’s interesting.

boats don’t travel well on land.

I’m landlocked.

The biggest reason is the miles per gallon a boat consumes sucks! You are lucky to get over 2 miles per gallon in a boat. I live 7 miles from work and it would take me 3 gallons of gas just to get to work and another 3 to get home. Next is speed most boats won’t travel much over 25 miles per hour. Lots of reasons to favor cars over boats the biggest is cars are cheaper own and maintain.

@Ltryptophan Yes, there would be issues, and it is interesting. Controlling water on a large scale takes a lot of work, energy, water, resources. Particularly in places where the water isn’t naturally approximately where you want it naturally. Much more than paving roads and repairing them. Think of things like leaks (possibly into other underground infrastructure), pumping, pollution, water plants, fish, birds, insects, sanitation, and then all the skills and related technologies needed. The interface with the boats and roads requires additional structures and transportation, etc. Venice works well partly because it’s not all that big and the people who live there like walking (also because the city is a designed as a good place to walk, and has established amazing places to be – cathedrals, art galleries, artisans, etc etc concentrated it one place). Contrast to the parts of urban Florida around Miami where there are also quite a few waterways and some people do have boats and go places on them (in fact, there’s the intercoastal waterway where you can boat all the way up to New England from there) but you can only get certain places, and most places you go, there isn’t all that much you can easily walk to, so you either only go where you’re going that’s near a connected waterway, or you need to dock your boat and get ground transportation.

Waterways are cool, but also complicated, and far easier to have where the water basically does what you want – which typically means flood plains, swamps, lagoons, etc that naturally have liquid water year-round.

Oh….navigating foul weather in a boat SUCKS! What would I do in the winter? Now I have to have a boat and a snow mobile. Ooops a snow mobile would require snow and we have not had measureable snowmobile snow here in Chicago all but 4 days. Looks like I would be riding a bike to work in January…..

I have been to Venice. I will just say stagnant water doesn’t smell good when you have boats leaking gas and oil into it. Oh, and drunk dudes thinking it would be funny to take a shit in the canal.

I don’t know what kind of boat @Cruiser is driving, but a boat that gets two miles per gallon has some serious issues in design, maintenance, fouling … or dragging the anchor. (Maybe he forgot to take it off the trailer when they launched.) Seriously, that is awful, awful performance.

Because the truth is … water transport is generally considered to be the cheapest of all forms, when all factors are considered, and that includes fuel consumption.

However …
– it’s nowhere near as fast as over-the-road transportation can be;
– there are major infrastructure concerns when canals are involved, which take tremendous capital to build and a lot of maintenance;
– winter travel is problematic in northern latitudes;
– you can only go where the water is – which might include lakes, rivers, and close offshore for some craft, but then there are additional infrastructure issues, and marine engineering and maintenance is far more expensive than patching roads;
– as noted above, navigation is an issue, because while it’s easy to drive along roadways that we can see, waterways (outside of canals, anyway) are not so visible, and “breakdowns” at sea or in unprotected rivers and large lakes can be deadly.

That’s just a few of the reasons. But you won’t know the history of the USA (and Europe) without understanding a bit about the history of canals in these places. This is why railroads were such a runaway success when they were introduced – even more than steamships – because rails could be engineered to go anywhere we wanted, even up quite steep mountains and down the other side. Canals “can” traverse uneven ground, but only at enormous expense.

Waterways are used in Venice, as many mentioned above. In southeast Florida. Many people travel by boat to go to dinner or see friends. Ft. Lauderdale is sometimes referred to as the Venice of America. Many cities have ferries to transport people. So, there are pockets here and there that do use boats as ever day transportation, or as a supplement to other firms of transportation.

In America, there are towns along waterways, and along the east coast many states drew their border at rivers. As you move west there isn’t as much water, unless you go way north, and not all waterways are connected. Traveling west many towns are along the railroads.

Ground transportation is generally way more efficient than water transportation. Generally, you can go faster, and it’s more organized, but there are exceptions.

@CWOTUS You clearly do not own a boat….I own three and can speak authoritatively as to the cost in gas it requires to have them moving across the water. I honestly do not know the exact MPG of my biggest boat but offer this posting at a boaters forum as a modicum of proof that I know how little I drive my boat and how much in gas I buy….

This is a thoroughly debated coconut with a similar answer to the length of a piece of string!

In very rough terms, and I now expect to be shot thoroughly, for budgeting and planing at 20 knots…

30’ 2–2.5 mpg
35’ 1.5 – 2 mpg
40’ 1 – 1.5 mpg

Most owners will likely and optimistically suggest their boat is far better than this, whilst wincing as they fill the thing up.

If you think about it too hard you will conclude in short order that the non obsessed would never own a boat, especially a planing power boat, but that’s where common sense and boat ownership part company !
Read more at http://www.ybw.com/forums/showthread.php?362380-Average-fuel-burn-rate-on-different-size-boats&s=8c581a7ac0e561d0648e360524ff0560#KD7v3juayDkXXIdp.99

I don’t recall the exact numbers but the vast majority of the energy used to get you from point A to point B in a car is used to move the car, not your puny little ass.
We certainly need to be looking for alternate methods of transportation (I just don’t think boats are the solution).

You need to get to the point A to point B very fast. You have a boat. To do that, you boat would have to have the motor and a propeller behind in order to get fast.
Now imagine what would happen if a fast boat went through the crowded street, right pass passengers.
Imagine walkers having to go across the water highway to get to the other side of the street. They’d need a bridge instead of zebra, and the bridge would have to be specifically designed to deal with both walkers and boats.

Besides that, the road water may get in touch with underground water and sewage, which would only create issues.

Not to mention you’d have to rebuild the cities completely in order to get traveling boats to work.
Water is much tricker than solid ground. Accidents can happen way more easily. One strong wind and your boat can turn over. Rains and storms can create much more ruckus on a boat than in a car. Boats/ships are much more unstable than cars, because they move on much more unstable surface. Again, since no one is crazy to paddle, your boats would need to run on a motor. Hence the inconvenience with power, controlling speed, and the passengers getting an unwanted shower every time some idiot passed on his stupid ass yacht, unless they’re high above the river-road, which again, leads us to complete remodeling of the cities.

Cars spend energy and pollute air, but are much faster, secure and more convenient in everyday use than boats.

Just sayin’ what I came up with. Captain probably knows a lot more about the issue, but I believe boats just aren’t an alternative to cars.

Addition: How would you deal with roads in between two places (Highways, I think they’re caled)? What about private vs public transport? How would emergency services deal with it, for example the ambulance, police, firefighters and similar? How to make a turn at the water-road?

We need dem cars.

You folks clearly live in the flatlands, try making navagable waterways up in the mountains.

For gas the 2 stroke engines have shitty, shitty efficiency. A 5 gallon tank being drained by a 70HP engine pushing a 16’ Aluminum boat may get you about 30 miles. Switch to a four stroke and you can ride around all day.

Why aren’t we flying them yet?

@AshlynM Oh but we are

Because there is very little water on land.

There used to be a restaurant at the lake we camp at. We had a boat for a few years.
Our camping spot was very, very secluded, on the other side of the lake. To drive to the restaurant would take a good 20 – 30 jolting, bumping minutes. But jumping in the boat and driving across the lake took <10. Plus it was really cool to pull up to the restaurant dock and there you were!
Dakota was our masthead. I bet it looked cool seeing this vintage boat cruising around the lake with a white wolf sitting bolt upright in the bow, usually.
At an Oklahoma lake they had floating bars. This was back in the 70’s. Don’t know if they still have them. You just cruised up and bought your drinks without ever leaving the boat.

Okay, @Cruiser, your clarification is noted. For boats of that size, yes, it’s obvious that fuel consumption is going to be much higher than in “personal size” boats (not jetskis or “personal watercraft” size, but, say lake fishing boat size). Because taking a 30’ boat “to work” on a daily basis would probably not be an apt comparison to, say, taking the family station wagon on the comparable road commute. And, yes, I’ve owned and used boats my whole life, but not in the size range that you clarified to specify.

@CWOTUS My “big” boat is an 18’ 6 cylinder inboard. My lake is 10 miles long and if I go up and down the lake (20 miles) I burn up half a tank 6 gallons so I get 3.3 miles per gallon. My sons 16’ 40 hp outboard will do the same trip on 3 gallons so 6.6 miles per gallon. The little 14’ 9 horse fishing boat will take near ½ the day to make the trip and burn up 4 gallons of gas or 5 miles per gallon. The jet ski though is the way to go as it will make the same trip burning up little over a gallon of gas and also in the fastest time in about 30 minutes.

I can’t believe you boys completely ignored my beautiful, emotional post to talk about cars and boats. I’m leaving you both! FOREVER!

But @Dutchess_III You didn’t tell how many mile per gallon your beautiful tri-hull got on the water

like, 0.11254.