Lake and pond construction
This page will outline the process of building a pond or lake and pond liner installation.
A large natural pond can look stunning and add interest and value to your home.
Just think how many estate agents use photos of a house taken across water when selling larger properties. With good advice, the cost of creating a fine pond close to the house may well be recouped in the increase in capital value and saleability of your home.
Many clients have said that their garden pond has given them more pleasure than anything else they have done to improve their residence.
Whatever the size and character of your garden we will create a beautiful natural pond that is easy to maintain and a haven for wildlife. It will be the focal point of your garden.
Building a pond or lake
Building a pond close to a house can create a useful transition between the formality of the building and the informality of the garden beyond. Alternatively, the pond may be sited some distance away, still in full view of the house, creating a beautiful focal point. It is important that wherever an informal pond is sited, it appears to be a naturally occurring body of water.
Beneath the water, the pond needs to have a profile that will allow aquatic plants to thrive, but only where you want them to thrive. If the pond margins are too shallow or too deep you might have a problem. The profile also needs to allow for pond maintenance and easy access into the water. If the sides of the pond are steep at the waterline, access will be difficult and getting out of the water may be problematic, and potentially quite dangerous.
Planning consent for building a pond
If you are building a pond within the boundaries of the garden then consent is rarely needed. If the site is outside the curtilage of the garden on, for example, agricultural land then change of use consent may be required. In these situations we employ a planning consultant. The process may take several weeks but we have never had planning refused. Planners and the EA tend to look favourably on new pond construction so long as you don’t alter a watercourse, flood plain or interfere with a protected habitat.
The process of building a pond
The initial site survey will tell us the levels of the ground we will be excavating and how they will influence the design of the pond construction. Soil type will also be ascertained. We will iron out any access issues for machines and lorry deliveries and determine how we re-landscape the excavated spoil as removal from site is expensive and to be avoided.
Along with costings, a written specification will be produced together with concept plans and pond construction drawings should they be needed.
Once the details of the project have been agreed the outline of the pond can be marked out. This is often done well in advance of construction so that the client has a clear idea of the scale and shape of the pond. This outline can often appear very large but the visible water's surface will be significantly diminished when planting in and around the water becomes established. It is important to build a pond as big as the site and budget will allow.
The pond is excavated to the agreed depths and profile. If under liner drainage is required it will be installed at this point, together with any overflow pipes and footings for decking legs.
If the excavation is very stony we will spread a layer of sand over the bottom of the pond as additional protection for the liner. The next stage is to install the protective underlay and then pond liner installation. Our preferred liner for large ponds is Greenseal EPDM which is a synthetic rubber membrane. A protective overlay is then installed in the pond margins where the planting beds are built and where the planting media will sit on top of the pond liner.
It is important that the pond liner is not visible above water or in the shallow pond margins. The excavated levels must be such that the grass turf at the waterline does not dry out due to it being too close to the liner anchored outside the pond. The grass must also not be allowed to get too wet or boggy. For this reason we usually install an overflow so that we can create a fixed maximum water level. This then ensures that excess water doesn’t overflow the liner and create a boggy area.
Building a clay lined pond
This article refers to importing clay to use as a lining material and not the construction of a pond into indigenous clay. However, we recommend rubber lined ponds rather than any form of clay.
We find a common cause of leakage is in clay ponds that have been built using imported clay to cover a porous substrate. Clay is rarely a good choice as a liner. It might seem good in theory and look good straight after installing but the chances are it will leak before too long.
If clay is to be used, good quality engineering clay should be put down in layers, using a sheep's foot roller vibrating compactor. The finished clay lining should amount to a minimum thickness of 400mm. Obviously, the excavation will need to be overdug by the same amount to accommodate the clay. The clay should be kept wet throughout the construction process.
Clay ponds are also more likely to suffer from the growth of invasive pond weeds which can take root in the bottom of the pond. This rarely happens in a rubber lined pond.
Ideally, the finished clay pond should have a permanent natural supply of water (not mains) keeping it topped up. The process of building a clay pond is laborious and expensive and a perfectly installed clay liner will still be inferior to a well-installed rubber liner.
Pond decking and water plants etc
Finally, the wooden decking can be installed. We generally build pond decking on top of the liner and not through it. Planting is then carried out when the water level is near the marginal beds.
A new pond might take as long as a year to settle down, though it is usually quicker than this. If a pond is built during the winter or spring then there is a good chance of it looking reasonably mature by mid-summer.
It should be noted that two or three years after construction, and sometimes sooner, plant growth may well have progressed to a stage that requires a small amount of annual pond maintenance. Even on a large pond this need not be expensive.
Follow this link for an overview of formal pond construction.
Our work covers a broad range of subjects including pond construction, lake construction, pond and lake restoration, pond maintenance, pond repairs, pond decking and other water-based landscaping projects in Hampshire, Wiltshire, Dorset, Berkshire, Oxfordshire, Somerset, Bucks, Salisbury, Winchester, Andover, Newbury and London.