We have a new nature pond, which is enjoyed by park users and birds. This was made in October 2016, with S106 funding, by Guy Belcher, the Gaskin Brothers contractors and garden volunteers.
Nature ponds should be in a sheltered sunny location, not too close to trees. We made ours in the main bowling green area, next to the tarmac path so people can get to it easily for pond dipping. The other sides are very shallow for both wildlife and safety.
The pond was made of a layer of geotextile, covered by pond liner membrane with a layer of geotextile on top. The shelves are covered with gravel, with some flat-topped stones and some logs from the park and local nature reserves.
Some water plants have been moved from local nature reserves and Guy's garden into the gravel areas and some oxygenating weed planted in pots.
The pond has a variety of depths and very shallow edges, for both wildlife (especially hedgehogs) and child safety. Bees and birds like to have a pond to visit too.
An accessible rail along a 3m boardwalk in the corner for pond dipping.
It has a bog garden area behind the pond, which one day we might get around to planting. It also has a hibernaculum (literally a 'tent for winter quarters'; instructions on RSPB website).
In the first Spring, wildflowers and pictorial meadow annuals self-seeded on the mound around the pond. In 2018, this was replaced by thick, long grass.
Two pond-dipping benches, with space for dipping trays, which can be used for seating too (or even taking a nap).
A mini-pond to transfer spawn to for close-up scrutiny - and sometimes there is a frog or two in it.
We need to complete:
The planting in the bog garden.
The woven hazel fence around the area - it needs a gate.
We'd like to work with volunteers from Cambridgeshire and Peterborough Amphibian and Reptile Group (CPARG) too - in ecology surveys etc.
Design of the pond - testing the area
In late April 2016, we dug three test pits at different depths, sampled the underlying clinker and clay and filled them with water. We found the clay to be very deep but not of sufficient quality to use on its own for a pond liner - it would crack and also probably wouldn't clear for good pond dipping and aesthetics. The water drained quite quickly too.
This was disappointing but means that we could revert to the original plan of using a mechanical digger, pond liner and geotextile for a quicker and less-risky technique.
We will be so happy if we can support a healthy ecosystem of caddisflies, dragonflies, frogs, newts, snails and toads.
In 2016, we spotted several frogs and a toad in the garden.
In March 2017, we had one small patch of frogspawn, which seemed to hatch.
On 11 May 2017, we spotted our first fat tadpoles (no legs yet).
Mallard ducks visit the pond at regular intervals - please don't feed them or they will dominate the wildlife of the pond (and eat it).
We will be careful not to introduce invasive species and ask people to not bring frogs and newts in but wait for them to arrive.
We will also have fresh nets for dipping for use in this garden alone - to help prevent invasive species in this new pond.