pond building

[scottb]

Mogsie as your in the same neck of the woods as me what mix would you use for the base and the morter. With the size pond I'm planning on building 10x7x5 this is going to have 2200 Gallons which in weight terms equates to around about 9 tonnes are you sure a single course 4'' wide wall will be stong enough on it's own

 

[mogsie]

right i have been thinking about this in depth, (ive been out in the my garden imagining i was starting your project) when another issue came to mind, not the weight of the water pushing out but the weight of the soil possably pushing in, are you building this on level ground ? or on a slope? do you have good drainage in your garden? about 2 or 3ft down you will come across yellow clay,(wolverhampton is sat on huge deposits of boulder clay and yellow clay) this is a bugger for digging but good and firm for building on ! below the clay it will get very rocky, this is mudstone formed from compressed clay, ideal if your foundations sat on to this and i would make them atleast 6" deep using a mix ratio : 1 cement, 2 sharp sand, 3 course aggregate. are you putting a full concrete base down ? now the walls, this depends on the factors i mentioned before, as to weather the surrounding soil is going to be moving/pushing against the wall, if your garden is well drained and level that shouldnt be an issue, as you will be infilling up to the completed wall with some good building rubble and pack it down well, so the weight of the water against the wall wont move it as it is well packed on the other side, if there is a chance of the soil moving and pushing against the wall then i would do 2 courses, laying 1 row of each course upright then second row on its side and continue in that pattern which will give the wall strength, if you go with this pattern continue right to the top and you wont have any worries atall, if the surrounding ground is level and firm and you go with single course then above ground you could switch to 2 rows to be sure,(the whole 9 tons isnt going to push up against the top 3 rows ) for the mortar i would make it : 1 cement, 3 1/2 or 4 sand, for a good strong mix.

 

[scottb]

Answers:- Garden is very flat and has very good drainage with very few puddles as you say the whole 9 tons wont be pushing against the top from what ive been told the most pressure as at the base where the walls join so i think i will go for the double course above ground starting about 6'' below ground level and backfilling the gap round the pond will a good strong concrete mix.
Thanks for all your advice have taken it all onboard

 

[sissy]

:If your going to walk on that top section it would give you better balance ,wouldn't want you falling in and end up swimming with the fish :dunno::fish::compute::bowdown:

 

[scottb]

I dont know about walking on it Sissy but plenty of sitting with a cold beer in hand just watching them swim about and trying to get them to feen from my hand, God cant wait untill summer

 

[mogsie]

make sure you get your corners keyed in well, hope all goes well, happy building !!

 

[sissy]

Ok beer and sitting on wall that could be worse if you have to many and fall in.Headlines MAN FALLS IN NEW KOI POND AND DROWNS .geeze not good .When you feed them don't lean over to far the first fall could be really wet

 

[DoDad]

What I do is put water in the pond and backfill and tamp dirt at the same time.

 

[sissy]

Just think about the end when all is done and the pond is running and those happy little fish faces smiling up at you .the joy not the work is the most fun happy ponding