Wild life pond deterioration

[NotMike]

Hello, a newbie here with a problem I saw mentioned in a very old thread, but with no resolution. Has anyone got any

idea of what’s causing the small holes in my 15 year old butyl liner in a wildlife pond? The photo shows the holes, you will also see (look carefully) holes in the process of being created from the inside of the pond, very gradually! ? I have ideas but not seen any suggestions on the forum. The holes, and what seems to be future holes, are developing in the region fron the water line to about 5cm below water line.


I have had a wildlife pond approx 2.5 x 3.5 m with max depth of 1m, for 15 years. Butyl liner and boulder edges. I have had leaks, one being a rodent? With gnawed hole, approx 1.5 cm. I have had other leaks, perhaps from birds (heron and rooks) who have grabbed frogs definately, and perhaps cats trying to catch frogs?. I decided it was time to add a new liner (or GRP). Not a small job as largest boulder is 100kg, and it’s DIY. I also have smaller holes, see above.

 

[j.w]

and welcome @NotMike
I have never had experience w/a Butyl liner, sorry. Weird that it gets the hole gradually like that! Almost like it is melting or burnt.

 

[GBBUDD]

add a new liner (or GRP)

never heard of grp

as to you holes could be a =boring worm or even a herons beak or roots but with roots and a heron it would be a puncture and not a hole

 

[Lisak1]

Those are some pretty precise holes. Like something used a hole punch!

 

[NotMike]

It’s been suggested to me that these holes might be caused by water creatures rasping off algae From the pond liner. Tadpoles or snails perhaps? I have loads of both. I have discovered many more similar holes, including a cluster spread over a horizontal distance of 30cm or so, on the side of the pond facing south.