Moat Construction Problem

WHY do I do it? Perhaps I’m being governed by the GIFT, but for no apparent reason this evening I posted the following to uk.d-i-y. Readers may recall my equally inexplicable posting on a few months ago that produced a very witty set of responses far funnier than my original post. This is one is equally weak, but I hope it’ll both fish in some suckers and spark some funny replies. Lets see if it works…

For the past three years I have been building an Anglo-Saxon castle in the garden of my house, 
using only traditional tools and materials.

Having laid the foundations and dug the moat, I would like to fill the moat so as to test its 
integrity (both of itself and against invaders) before progressing to erecting the walls.

I understand the traditional way of doing this is to tap a river or a stream, and supplement 
this with ox-drawn carts filled with barrels of fresh water. However, being in Brockley, I'm 
too far from the Thames to do this (a distance of about 2 miles as the crow flies). There are
also no tube stations near enough for me to tunnel the water from there. While I think I could
construct the necessary carts, I would not have the space in the remainder of my garden to rear
the oxen to draw them. My neighbours have made some comments on the fact that I have begun 
rearing goats and some chickens to produce the considerable tonnage of dung for wattle daub 
I will need later on in the construction.

So I am considering using a Chinese technique from about the same historical era of using 
giant kites to lift Thames water into place above the moat and pour it in from there.

Does anyone have any experience with this particular technique (which, I understand, will 
require considerable resources and manpower to implement), or indeed defensive Angle-Saxon 
moat building in general?

Any advice much appreciated. And if you also have any tips for laying long-and-short 
quoins I would also be grateful as my initial attempts at this were not successful.