In article ,
David Hill wrote:

Anyone who might flood or need to divert water might find this interesting
product useful. We now have some from Travis Perkins Builders Merchants but
hope we won't need to employ them. Missed the army delivery of sandbags as
we were out! No I don't understand the logic either.

http://www.floodsax.co.uk/floodsax/

The hype is, as always, hype. They will have a density of about 1,
whereas sandbags will have a density of above 1.5 (especially when
wet). So they will work only if they are piled high enough that
the weight of the ones above the water holds the ones below the
water on the ground.

A neat idea, but you clearly MUST be aware that they need to be
piled 50% higher than sandbags to work at all.

Talking to a technical bod from a firm making water retaining polymer
last autumn, he reckoned that as a substitute for sandbags they just
weren't in the same league.
Sandbags every time.

If feasible. The point where those score is that you can store
them in a small amount of space, and don't have to rely on a
delivery of sand.


Regards,
Nick Maclaren.