Ship canal maintenance less than barge canal?

[AP]

Barge canal is cheaper than ship canal to build (logically), but oddly, the ship canal is cheaper to maintain. Is that right?

[jamespetts]

This is an error and will be corrected in the next version. Thank you for pointing it out.

[wlindley]

Related: The tub boat aqueduct and the masonry barge aqueduct seem to be missing the ability to convey those types of vehicles? The restriction is not displayed, and the proper types of barges and boats seem unable to use them.

[MCollett]

Barge canal is cheaper than ship canal to build (logically), but oddly, the ship canal is cheaper to maintain. Is that right?

I don't know about maintenance costs, but the ship canal construction costs are far too low.   Current prices (per km) are:-

Narrowboat: 150
Barge: 400
Ship: 300 (600 before 1822)
Large ship: 400

Historical comparisons:
Bridgewater (barge): £220 thousand for 66 km = £3330/km (in 1761)
Staffordshire and Worcestershire (narrowboat): Over £100 thousand for 74 km = >£1350/km (finished 1771)
Trent & Mersey (narrowboat): £296 thousand for 150 km = £1970/km (finished 1777)
Gloucester & Sharpness (ship): £440 thousand for 25.5 km = £17250/km (finished 1827)
New Junction (ship): £300 thousand for 9 km = £34000/km (finished 1905)
Manchester (large ship): £15 million for 58 km = £260000/km (finished 1894)

These are all up, including earthworks, tunnels, aqueducts and other associated construction as well as the watercourse itself, but give a reasonable feel for the relative costs.  Retaining the current cost for the narrowboat canal, I suggest something like:
Narrowboat: 150
Barge: 300
Ship: 2400
Large Ship: 25000

The last is comparable to the per km cost of major earthworks, or of a railway tunnel; it certainly shouldn't be less than the latter!

Best wishes,
Matthew

[jamespetts]

Related: The tub boat aqueduct and the masonry barge aqueduct seem to be missing the ability to convey those types of vehicles? The restriction is not displayed, and the proper types of barges and boats seem unable to use them.

I can't reproduce this, I am afraid. Can you give any more details?

Matthew: that is very interesting information - do you mind me asking what the source is? That should probably go into the snippet thread.

[MCollett]

Matthew: that is very interesting information - do you mind me asking what the source is?

Most of those construction costs are just from the corresponding wikipedia pages, though I had to look elsewhere for the cost of the Trent & Mersey:
http://www.canalroutes.net/Trent-and-Mersey-Canal.html

Best wishes,
Matthew