Water Features Built Using Plastic or Rubber Pond Liner
Economic tips: Estimating the size of your flexible liner is simply the length plus twice the depth by the width plus twice the depth. (Add on an extra 50cm to each dimension too if you are adopting the conservationist technique below) You will save money by ensuring that one of these measurements corresponds to a standard width off the roll.
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In gauging the effort involved, it would not be too much to expect 2 fit men to excavate 10 cubic metres in a day. Double that, in excavating a pool 6metres by 7metres and just over half a metre deep, they would begin to lose site of the end of the task and it may be more economic to call in some mechanical help. This in turn would be more cost effective if you hired a digger with an owner-driver. These guys can usually make their machines do the dance of the sugar plum fairy if you wanted them to, and a competitive cut-throat world ensures they will do the deed for little more than you would pay for a skilled labourer. They can do the bulk of the earth moving but the final details of profiling will still have to be done by hand. The delivery of the excavator is usually a major cost to consider, so keep your enquiries as local as possible.
1. Take a sturdy peg longer than the depth required for your pool. Mark the depth on the peg and drive it into the ground to the expected water level. Excavate to the level marked on the peg. This is your datum peg, so ensure it remains undisturbed.
2. Using your datum peg level, cut a V shaped trench, around the inside of the proposed shape of the pool. The inside edge of this V needs to be no more than 5cm below the level of the datum peg. The depth of the V needs to be just over 25cm deep. The outside edge has to be consistently above that level and needs to slope gently away from the pool.
3. The excavation should gently slope down at 30 from the V to the required depth.
4. Consolidated the hole and remove sharp stones. Line with soft sand and a protective underlay material.
5. Open out the liner in the hole and fold into place. Collect as many of the creases up together as possible into one fold. don't let the water stretch it into place. Life just aint that simple.
6. If you are completely committed to the natural look then drape underlay in strips on top of the liner. After that sub-soil used to be laid on top of that. Nowadays though, it is thought that in order not to burden future cleanouts with tons of inseparable mud, the underlay is left to accumulate sediment and detritus through the normal activity and development of the water garden eco-system. Live with bacteria, the underlay soon becomes obscured under sediment that is unless the underlay floats to the surface in the meantime.
Ensure this underlay does not emerge from the V and go on to end up lower than the water level, otherwise it will end up as a wick capable of siphoning the pool dry.
7. The V can be filled with soil and planted. It can work as sort of hod for pebbles creating a beach effect or it can contain the concrete footing for an upright timber edging.
When things are not so simple: When part of the pool edge emerges above the level of the surrounding landscape, or if the pool is in loose soil or made up ground.
Establish your datum peg as above. Excavate the pool area as much as necessary. If you are intending to face the inside of the pool with stone work or brickwork ensure your marginal shelf area is wide enough to support this whilst leaving enough room for plants to sit in baskets Use the datum peg and several intermediary ones level with it around the excavation as reference in establishing a blockwork framework. In loose soil or made up ground this blockwork will need a footing into consolidated soil (see above for preformed pools).If the pool emerges from the ground to its full depth, the marginal shelf needs to be constructed from blockwork too and backfilled with sub soil.
This will be the skeletal structure for your pool, which will be lined with sand and underlay (particularly on the upright blockwork) and can be faced outside and inside with your choice of materials.ANOTHER TIP OR TRICK: To have a pool brimming with water
This simple pool has a skeleton of blockwork laid onto a thick mortar mix straight onto soil.
A granite set edge is supported by the blockwork whilst the liner comes up behind the sets. In this way, the water level in the pool can be maintained almost flush with the top of the edging stones.