(note: click on thumbnails for LARGE images - use BACK button to return- place your mouse over a picture for details)
Before we started
The pond appears to have been built when the house was constructed in 1929. It was kidney shaped and about 16' x 8'. The pond was made of concrete and stone. The original installation was a base of 2" of concrete on a bed of cinders. Over this was stone face with each piece of sandstone mortared into the pond. As you can see from the 2nd and 3rd pictures below the pond did hold water.... but only for a short time!
In order to install a liner and make the pond watertight all of the existing stone and cement needed to be removed. This was done with a sledge hammer and digging bar. About 20 hours over 4 days did the trick! The last two pictures give some idea of the amount of concrete scrap that was generated.
A number of repairs became evident during demolition. The most significant was a repair to the deepest part of the pond that was done with 2" to 3" of heavy tar topped by another inch of concrete. This made removal of that section VERY difficult Note the thick layers of tar and the large slabs of stone and concrete that were pried up.
The new pond will be slightly larger than the original. The main difference will be a raised "bog" that will take up about 1/3 of the surface area. This bog pond will provide a home for many plants and will provide filtering for the rest of the pond. It will also have two spillways to return water to themain pond. The first step was to create a shelf around most of the pond that will provide a place for plant pots.
Construction (bog area)
The bog is separated from the rest of the pond by a wooden shelf that will be capped by stones once the liner is installed. Boards were installed on the face of the shelf to hold back the fill that will raise the bog.
The transition from the bog to the main pond is represented in a model that helped during planning. Large Belgian blocks will be used to separate the two sections of the pond.
The bog takes shape. Concrete block forms the back wall. The maze of black tubes make up the discharge from the pump that will push waste material from the main pond through the lava rock that fills the bog.
Installing the liner
The underlayment (like heavy felt) and liner (45 mil EPDM) were installed next. The single sheet of liner that was purchased was 23' x 30' and weighed nearly 200 pounds. We decided to cut it into two pieces and to line the bog and main pond separately. This proved to be a wise decision as it simplified installation and cut down on the number of folds and pleats in the liner.
Cementing the front of the bog
The face of the bog is lined with two courses of Belgian block. Dan Sebolt, expert brick layer, directed the project. 75 pounds of masonry cement and 130 pounds of fine sand were used. Two pieces of 18" square x 1/2" slate were used for the two spillways. They were cemented in and glued to the liner with black silicon sealant.
The bog is just about done!
Lava Rock is red!
The bog was is filled with 1040 pounds of red lava rock. It was transported from the supply yard in the back of the Explorer (see picture) in two trips - one carrying 460 pounds and one of 580... Lots of shoveling! The lava rock turns water red from the powdered rock that is always present. Several rinses and a complete drain / refill of the pond did the trick.
Add rock and we are (almost) done
The edges of the pond and shelves are lined with the rock from the old pond. We had virtually none left over.
Some plants and Waldo (the frog)