The Construction of my Ponds - Page 2 - The First Rebuild
How it all began Second Rebuild (1) Second Rebuild (2) Second Rebuild (3) Third Rebuild The Final State
The bridge was the final part of the puzzle. Now we could start working out just what we wanted. We knew that the bank at the far side of the pond had to go and that we didn't want to rebuild the bottom pond. We also knew that we wanted to bring the pond system as close as possible to the house but other than that, we were not too concerned. I can't stress enough though that if you are trying to build a natural looking pond, the whole thing has to look as if it meant to be there. If we were bringing the ponds closer to the house, that more or less fixed the position of the filter box so that was our starting point. The next step was to move all the plants that were in the way and to wreck what we had.
With the decking out of the way and the old top pond emptied and the liner removed, I was able to dig away the bank at the back of the pond and the earth from the bank was used to build up the area where the new top pond was to go. Once again, the garden looked like a building site. My original idea was to have just three ponds but when I started digging the middle one out, I found the concrete base that was the original top pond following my first reconstruction and which I had buried in the intermediate stage. I couldn't be bothered digging up all the bricks and concrete that I knew was there so three ponds became four and the location for the bridge was confirmed as just below the second waterfall. The hole at the right of the picture is for the filter box and the green hose contains the mains cable for the pump and UV filter.  Top
The first thing to be constructed was the base for the top pond. This had to be able to support the weight of water within the pond as there wouldn't be enough pressure from outside the pond because the side next to the liner in the picture would be at the top of a rock wall and I wanted to edge the other side of the pond with the heather plants that I planted years ago during the first reconstruction. The blocks were about £1.50 each at the local builders' merchant and were just rough concrete. I bedded them into a layer of cement and used some earth to hold them in place as the cement set. The filter was set into the ground and the output pipes fed into the pond. I was worried that water would go from the output pipes straight out of the pond over the adjacent waterfall which would have meant that with no flow, part of the pond could have become stagnant. so I used earth to make a bit of a ridge down the middle so that the water would flow down the pond and back again. With that part sorted out, I got on with the liners for the middle and round ponds.
In this picture you can see that I have got all the liners in place and have filled the ponds to ensure that the liners have settled in place correctly. However, note that I have emptied out at least a couple of inches from each one so that I could build the waterfalls. Although cement sets through chemical action rather than drying in the sun, you have to give it a fighting chance and it won't seal properly if the water can seep into the cement. Also, you can see that I haven't trimmed the liners yet. That cannot be done until the water is flowing. Few people have a level long enough to set the levels across a pond but if you have a length of 50cm x 50 cm timber, you can use that with the level on top. The sides of the ponds (and any streams) need to be no less than about 3cm higher than the top point of the waterfall stone / slate. That is because the waterfall will get covered in fibrous weed which grows at a prodigious rate in the summer and which can effectively raise the level of the water in the pond by about 1 cm. Just in case I have made a mistake with the level, I always delay trimming the liner until the water is flowing properly around the system and all levels are at their maximum.
With the waterfalls dry and the water flowing, I trimmed up the liners and installed the bridge so that I could get to the far side of the system. I wanted to make a path down to the bench which I intended to put across the corner at the bottom of the pond. If you look in the gardening textbooks for this sort of path, they all advise putting down a membrane under the gravel to stop the weeds. But I wanted my path to look as natural as possible so I didn't want to stop all growth. Instead, I carefully cleared the path of all perennial weeds and laid a number of large flat stones along the path. These were to be stepping stones through the gravel because I tend to walk around barefoot in the summer and its easier on the feet to walk on the stones than gravel. Don't get the stones in too much of a line and vary the sizes as much as possible.   Top
As you can see from the mud in the picture, the ground was quite soft so a good stamp on each stone was all that was needed to make it nice and firm. You don't want them to rock. Then I simply poured the gravel over them and spread it round so that the gravel was level with the stones. I have called it gravel, but it isn't the course gravel that you would find on a driveway; rather, its small rounded stones that I got from a garden centre. They are usually sold in 25kg bags so be careful lifting them. I used a mix called "Brown and Beige" because they matched the colour of the rocks that I was using. Once the path was finished I planted some rockery type plants at various points along the edge to help make it look more natural. Since the ponds were complete I have had a lot of plants self-seeding amongst the gravel and I simply remove those that I don't like and leave those that I do. Weeds can easily be seen and are easy to remove on a regular basis.
This type of bridge is extremely sturdy (this one has supported 3 adults without even a creak) although again, you must think of safety. If young or infirm people are going to use the bridge, it may be better to get one with a support rail so that the risk of falling into the pond is minimised. The total span of my bridge is 7 foot. My wife bought it for me at my local garden centre and was horrified when I promptly took it to bits and redmodelled it so that the end ramps were not so steep. I positioned building blocks under the ends so that none of the corners could sink into the ground and render the bridge unsafe. Remember that, as with all other wooden items exposed to the elements, it is important to keep the bridge properly maintained. When treating the wood, don't forget to paint the underside as well.
This is what the path to the bridge looked like by the end of the summer. As you can see, the plants at the edge of the path are now established and the path looks quite natural. The path is quite clear here, but in the following spring, I found that a huge number of mimulus, iris, and grasses appeared. I let them grow until they were big enough to handle and then transferred them to other places in the garden.