Pond Creation

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Ponds are permanent or seasonal waterbodies between 1 m2 and 2 hectares in surface area (about 2.5 football pitches). This definition includes:

  • temporary ponds that dry up in warm weather during the summer months
  • any that occur during the year, as well as tiny waterbodies
  • pools and very shallow ponds
  • ‘wader scrapes’

Ponds can be around for 100 years and often longer!

Why create a pond?

There are many benefits for wildlife! Creating a pond brings enormous benefits for wildlife, as 80% countryside ponds are now degraded. A pond will provide increased habitats for many species as the pond ecosystem is diverse and it provides an important part of the lifecycle for many creatures such as caddisflies, dragonflies, frogs, toads, newts and midges. These are in turn vital for the food chain, providing food for birds and mammals.

There are many benefits for people! Creating a pond, walking around or to them, discovering the creatures that live in them are all ways of keeping physically fit and the mental health benefits of being outside in nature and near water in particular, are well known. Nature deficit disorder was coined by Richard Louv and describes the disadvantages to modern children of being deprived of experiences in nature. The mental health benefits of reconnecting with nature are proven to be huge.

Since the beginning of the 20th century 75% ponds that existed then, have been lost and there are now approximately just 478,000 ponds throughout England, Wales and Scotland. Although there are many lakes and lochs in the UK, ponds have shown to provide a greater conservation value than lakes, due to the increased number of invertebrates and rare animals. Two thirds of all British freshwater plants and animals are found in ponds and the biomass of aquatic plants is vitally important for carbon capture.

Types of Ponds

Every pond is different and contains different species, depending on the location, surrounding habitat, micro-climate, water acidity and underlying rock type.

Ponds have shallow sloping sides which are important for emerging froglets and areas with deep parts for animals such as toads. The size and number of ponds in an area is important as a few ponds provide a greater length of shallow edges and there is greater diversity of species, as each pond is different.

The permanence of a pond creates a different habitat – some are seasonal, and shallow, whereas others are deeper and therefore more permanent. Pond liners keep water, so these ponds are more permanent and less likely to dry out. Historic ponds are interesting as they were often created for cultural uses.

  • Village ponds were created for animals to drink when travellers passing through, people to swim and skate.
  • Agricultural ponds provided water for farm animals, and were regularly cleared out so the mud could be used to put on fields to fertilise the ground
  • Fish ponds were created in the Middle Ages to hold fish stocks for food.
  • Duck decoys date from the 16th century, when ducks were enticed into a pond then lured into tunnel nets by dogs.
  • Moats were created around houses or castle in the Middle Ages, to keep intruders out but also to keep fish and to dispose of rubbish.
  • Mill ponds were created to supply gravity-fed water to power the mill
  • Hemp and flax ponds removed waste materials during the manufacturing process.
  • Liming ponds were used for dehairing and curing animal pelts
  • Gravel pits when filled in with water create important pond habitats
  • Peat pits, when peat was cut, ponds were created in the process, providing habitats for wildlife.

Clean water ponds do not have excess chemicals or sediment leaking in from the surrounding environment. They require minimal management as there is little requirement for sediment dredging or other management. They have a high biodiversity value and a long lifespan – most clean water ponds will survive for hundreds and sometimes thousands of years. They also have few long-term problems such as cloudy water, excessive algae or duckweed.

It is better to create a new clean water pond rather than maintaining an existing pond. This is due to pond succession as you find different animals and plants at different stages of a pond’s life. If maintaining a pond, you have to survey a pond to make sure you are not affecting existing populations of rare animals, such as great crested newts, and this can be expensive. Also, you can site the pond somewhere with a clean water source, in a suitable location.

Pond Location

There are many things to consider when siting a pond:

  • Water source – needs to be clean,
  • Local land use – should be non-intensive, so no fertilisers, pesticides or nutrients will run in.
  • Inflows – do not have stream, ditch or drain inflows running into the pond, as they bring in pollution and silt, so the pond silts up quickly. Ground water or surface drainage is the best form of water input. Do not add topsoil to or near the pond as it contains high amounts of nutrients (nitrates, phosphates, heavy metals, pesticides, fertilisers). Clay or sand is best.
  • Existing habitat –don’t dig a pond in an area that is already an important habitat for wildlife. Good examples of sites include low intensity grassland, woodland, scrub.
  • Connectivity -dig ponds near other wetlands to improve connectivity. It is good to dig ponds where uncommon species occur to help strengthen their populations.
  • Likelihood to hold water -Local geology,hydrology.
  • Sun & overhanging trees- ponds need light and if it is near trees, the leaves drop into the water. It is alright to have trees on the north side of the pond if it is big.

Investigations

You need to find out what is under the ground and find out some information before starting!

  • Archaeology-survey or find information
  • Underground pipes and services- underground cables and pipes for electricity, gas, oil, water, telephone lines, sewage.
  • Above ground services: – check the maximum height of machinery that can be used with overhead power lines.  Electricity can jump to close equipment.
  • Neighbours – contact neighbours to alleviateconflict, and check your neighbour’s drainage system.
  • Planning permission if necessary
  • Trial holes – will it hold water?
  • Slope
  • Bedrock
  • Soil type
  • How quickly it fills with water
  • Spoil – where will it go?

Lining the Pond

  • Dig the pond out with shelves to put plant pots on and shallow areas at the sides.
  • Get it level so the water does not overflow at one end.
  • Put sand in to cover any roots etc and help protect the liner.
  • Put underlay in, to protect the liner.  Overlap two pieces if necessary.
  • Stand on the liner IN SOCKS to ensure that all areas are covered. Once water is in you do not want it to pull the liner down and potentially mean you have less liner.
  • Cut the edges of the liner to fit but leave some extra around the top.
  • Add stones.  This is not compulsory, but it does help keep the liner in place. Ensure they are not sharp and will not cut the liner.
  • Dig a trench round the outside of the pond to bury the liner into. It needs to be fairly deep to completely cover the liner.
  • Fill in the trench with soil and pack it around the stones.  Leave it to fill with rainwater naturally.

Pond Design

Bank angles are important as the most diverse area of a pond is its shallows and for wildlife the best part is 2cm deep. Therefore keep most bank angles very shallow with a broad, almost flat zone near the pond edge (less than 5°).  Pond water levels rise and fall during the year. The average is a 30 – 80 cm drop between spring and autumn. Consider this in your design, so that there are always areas of shallow water.

Underwater topography needs to be planned.  Many of our native submerged plants, including stoneworts and pondweeds, grow best in areas free of the organic sediments that build up in ponds though time. These plants prefer bare clay or sand, so create underwater bars and shoals. The fine organic silts slip off the top of the bars and accumulate in the troughs below, leaving the top bare for plant growth.

Pond Shape is important. Scalloped edges give a longer circumference of shallow edges

The pond depth should be at least 60cm so amphibians can hibernate if water above is frozen.

Pond Creation Tips!

There is no best time to create or manage a pond. In winter there are hibernating amphibians, in spring they are spawning and in summer they are full of invertebrates. You could also make hibernacula nearby for amphibians, for example, logs or sticks with soil on top.

Things NOT to do:

  • Deepen seasonal ponds
  • Remove more than ¼ pond’s sediment over 3 years
  • Remove more than ¼ vegetation over 3 years
  • Link ponds to drains or streams
  • Steepen the edges
  • Allow the catchment area to become more intensive
  • Drain the pond
  • Destroy a habitat type
  • Cut down more than ¼ trees in/around pond over 3 years.
  • Clean water supply
  • Let dogs in ponds as they disturb vegetation and stir up sediment
  • Add fish as they stir up the sediment, eat frogspawn and newt larvae
  • Let birds in as guano adds nutrients to the pond
  • Introduce amphibians as they spread disease
  • Add tap water as the nutrients encourage algal blooms
  • Introduce invasive non-native invertebrates such as the killer shrimp
  • Introduce invasive non-native vegetation which will spread uncontrollably and out-compete native vegetation.

Pond Succession

The pond gets shallower as it fills with sediment, then marginal vegetation creeps in. The end point is a seasonal pond, wet in winter, dry in summer which is stable for hundreds of years. There is never dry ground, even at the last stage of succession. Most importantly, this is a natural process – all stages are important.

Plants

It is good practice to leave the pond to colonise naturally. Freshwater plants are adapted for dispersal – freshwater plants disperse by duck’s feet. New ponds provide a special habitat. In the first summer you get annual plants, then after a few years aquatic and marginal plants will colonise.

If you need to plant, use native plants of local provenance – in urban areas they must be from within 10km. It is illegal to uproot plants without the landowner’s permission. Garden centre stock can be non-native.

Native plant species

  • Marsh marigold
  • Water mint
  • Lesser spearwort
  • Water forget-me-not
  • Marsh cinque-foil (photograph below)

Invasive species you do not want in or near the pond:

  • Canadian waterweed
  • New Zealand pygmy weed
  • Giant hogweed
  • Himalayan balsam
  • Japanese knotweed
  • Water fern (Azolla)

Wildlife

Wildlife will also naturally colonise your pond. Here are some of the commonly found species in ponds.

Amphibians:

  • Frog – hops, smooth moist skin
  • Toad – crawls, dry warty skin
  • Smooth Newt –most commonly found.
  • Palmate newt – prefers acidic conditions such as peat bogs.
  • Great crested newt – our biggest newt and a protected species.

Water invertebrates will quickly colonise the pond. For example, dragonflies will lay their eggs directly into the water or onto vegetation. Do some pond dipping to find wonderful creatures such as:

  • Pond snail
  • Dragonfly nymph
  • Damselfly nymph
  • Water boatmen
  • Water beetle
  • Caddisfly larvae
  • Whirligig beetles

Further resources:

Create A Pond

The Pond Book: https://freshwaterhabitats.org.uk/pond-clinic/pond-book/

Froglife: www.froglife.org

TCV Waterways and Wetlands handbookhttps://www.conservationhandbooks.com/waterways-wetlands/

Author: Faith

additional photos from The MAC-CAN Croft and Lucy