Confused about my stream construction

[Liz k]

Hello,
I am located in Washington State. I inherited a neglected pond when we moved here 3 years ago. The pond is 20
years old.
I have been cleaning out the pond, emptying it almost completely. I have an underlayment geotextile on top of the pond liner in much of the pond.

In the stream section that connects the upper and lower pond I found there is what looks like 2 layers of underlayment with clay in the middle. Sorry the photo may not be clear. The clay in the pulled back pieces of underlayment is beige/tan.
Roots are from plants that walked out of their pots for probably 15 years.
Any ideas why the clay layer?


Thanks in advance

 

[Mmathis]

Hello and welcome!

Do you have underlayment on top of or under the liner? Just clarifying.

No expert, but if the pond is old, and wasn’t managed well, the roots could have encroached on the geo layer, and taken the clay along for the ride.

 

[Liz k]

Yes, the underlayment is on top of the liner. I am thinking the original install was to protect the liner from animals etc. I live in a forest so lots of deer and racoons with an occasional bear.
There is an extra layer of liner under some of the very large rocks as well. I have been thinking this was a belt and suspenders construction
I have never had a pond so a lot of this is guessing on my part with some input from a local nursery that has ponds.

 

[j.w]

and welcome @Liz k

I'm in Arlington, Wa. so we are neighbors depending on how close you are to me

 

[Liz k]

Hi @j.w
I am in Bremerton. Thanks for the welcome! We had a lot of goldfish but when we were out of town last October something came in and disappeared them all except for one lone little guy. I figured with all the fish gone (didn't find the one survivor until after I started cleaning) it was time to do a clean-up which resulted in this massive renovation project. It started with getting out the invasive yellow flag iris and hanging sedge and snowballed from there.

I'm in Arlington, Wa. so we are neighbors depending on how close you are to me
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[Lisak1]

I would also concur - the plants brought the clay between the layers. They have an amazing ability to attract and collect dirt.

 

[GBBUDD]

Yes, the underlayment is on top of the liner. I am thinking the original install was to protect the liner from animals etc. I live in a forest so lots of deer and racoons with an occasional bear.
There is an extra layer of liner under some of the very large rocks as well. I have been thinking this was a belt and suspenders construction
I have never had a pond so a lot of this is guessing on my part with some input from a local nursery that has ponds.

i'm going to guess that in the pond it had clay at one point and with clay the fish root all across the bottom which fish do and the water was never clear. and in time probably even started to loose water due to the clay always being disturbed,

the stream not having fish would eventually find its happy place and not have the silt mucking up the water

i would look at adding a liner to the stream the clay will allow plant roots to dig in deep making for a landscaping nightmare trying to pull them. and in doing so youll take weeks to clear up the water. with a well designed bog filter it may clear in a day.