Chapter 5

The pond, the bog, and the waterfalls

Part III

Kieran Egan

The Bog

A pond in which fish are to live cheerfully needs to have water with certain qualities. A pond owner, as I now suddenly was, had responsibilities to future fishy tenants. A system was required that would clean the water of waste from the fish and keep algae under control, and prevent sludge and anything else undesirable from making its way into the pond. It looked lovely and clear now, but the time would soon come, despite my meticulous early efforts, when all kinds of detritus would be floating around and sinking down, and algae drifting on easy breezes would dive eagerly into the water and philoprogenitively multiply like crazy.

There are two solutions offered in the books. All recommend a biological filter. That is, a filter that will deal with the microorganisms that can play havoc with a pond and its life. I had a small "mechanical" filter on the pump&emdash;that was just a plastic grill to prevent the pump sucking up bits too big or hard for it to digest, but it did nothing for the water. Some of the more ambitious books recommended as the best solution a biological filter bog. The company that made the pump also made a molded filter bog in three sizes. My pond would require the biggest. One pumped the water along a flexible hose from the bottom of the pond into a connection on the plastic bog. This shot the water down to its base first, and the water then filtered up through layers of diminishingly sized stones, emerging at a lip that formed the beginning point of a stream that would carry the water back into the pond, cleaned. This looked very complicated, space consuming, and expensive. The size of bog I would need would run me more than $500. If people were willing to pay this for a piece of molded plastic with a few holes, I clearly needed to invest in the company rather than buy its products.

What to do, again? I wandered around various water garden shops, and all offered those round filters with pads that one puts at the entrance to the pump. The pump sucks the water through the filter, drawing algae and muck and waste matter into it. At weekly or so intervals, one pulled the whole thing up, unwrapped the pad, and swished it around in a pail of water to clean it, then one would fit the pad back around the filter, and lowered the whole apparatus into the pond. This seemed a lot of rather slimy work. I want you to know that if that was what it took, I would do it, but I frittered away a few weeks looking around for less troublesome alternatives and asking questions in the various shops. I had put a pile of oxygenating plants into the pond, so didn't mind taking a while as they helped the pond become more habitable for fish.

One trouble, and half relief, was that none of the filters I saw fitted my pump. But, it turned out, the company that made the pump, and the plastic bogs, had a very neat-looking set of filters that would slot easily onto the pump's intake opening. In the end, deciding I had to do something, I went to the landscape supply company where I bought the pump and asked for some of those biological filters. But the guy wouldn't sell them to me.

"They're useless," he said, leaning on the counter with his arms spread wide as though ready to accept a fight about it. This seemed fairly uncompromising. A young, tall man, he had a curious manner of looking away from one while speaking. Not in the usual way of perhaps shifting one's eyes to something close by and then back to the person with whom one was speaking. He gazed fixedly at something in a distant corner of the shop, as though he was watching it carefully. Then he would shift his gaze to something in an opposite corner, which also required his full attention. This was a tiny bit disconcerting.

"Well, what about those big filter bogs? Should I get one of those?" I had seen them hanging at the rear, hooked on the wall, with their soul-sapping prices attached. Perhaps the shop policy was to rubbish any cheaper solution and pressure innocent fish-loving customers to buy the plastic bogs.

"No. They're too expensive."

Well, we agreed about that, but what was I to do?

"Well, what should I do?"

"Buy some liner and make your own bog. Dig a hole, line it, and put layers of stones in, cover it with six inches of pea-gravel, just like you would have to in those fancy rigid bogs. There you are, for a tenth of the cost."

"Even less, as I've got a lot of liner left over from the pond."

"There you are," he nodded convincingly at the decorative stones in the rear corner. "Those filters you attach to the pump are useless. You need a filter bog, and it will take care of itself once its built. For a pond like yours," he paused to stare critically at the light fixture, "you'll need to make it about four foot long, by three foot wide and three foot deep. A good biological filter bog. That's the only way to go."

So that's the way I went. I did leave the place feeling quite cheerful at having saved a lot of money, and a tad bemused that he wouldn't sell me either of the expensive items I would have bought. To compensate him, I bought my first water lily, and a few heavy bags of pea gravel. I also bought fifteen feet of one inch diameter "professional" hose to carry the water from the pump at one end up to the bottom of the bog at the other, and a stainless steel clamp to attach the hose to the pump. But I also left feeling a bit daunted at the prospect of having to build a large bog. I had imagined that buying and sticking a filter onto the pump would be enough. But he'd convinced my conscience that I owed it to the fish to give them a proper filtering bog. Still, I did go home quite encouraged. At last a decision had been made, and I could move forward after some weeks of shilly-shallying.


Lowering the pump:

First I decided to get the pump rigged up, with the black spiral hose attached, and then put it in place sitting on a couple of bricks at the deepest point of the pond. I cut an extra piece of liner on which to set the bricks, to protect the pond base. The easy way of doing this would be to climb into the pond and simply put them neatly one of top of the other. But the water was cold, and I really didn't want to climb in. I think I also feared I might puncture the liner if I stood on a stone or something; in fact I'm not quite sure why I seemed to have concluded that I had to do everything from the sides of the pond. Perhaps an Irish way of avoiding one inconvenience, but creating and having to deal with a dozen others because of it.

Anyway, instead of doing the simple thing and getting cold legs for a few minutes, I rigged up the following unstable apparatus, remembering to attach the hose after I'd taken the picture:

The problem was how to lower a square of protective extra liner, with a couple of bricks on top of it, with a pump on top of them and a hose attached to the pump, to the bottom of the pond. Lying in bed was the best place to deal with these problems. So I visualized cutting holes in the corners of the liner which would stick out beyond the bricks. I would run long pieces of string through each hole. The string would be doubled, so that once the three hydronaughts hit the bottom of the pond, I could release one end of the string at each corner and pull it out.

This visualization of the smooth operation somehow had a bit of trouble with reality. My wife came home one day to find me proudly standing over the apparatus in the picture&emdash;so proudly that I took the picture. I persuaded her to take two of the strings, after I'd attached the hose to the pump, and I would take the other two, and we would stand on different sides of the pond and gradually lower the slipping, sliding, twitching apparatus to the bottom of the pond. She looked at the whole thing rather more skeptically and less admiringly than seemed to me appropriate. Even though it quickly became clear that she was right, and that the whole thing would stay steady only if we were holding it with exactly the same tension, and lowering at exactly the same pace&emdash;which we couldn't manage. This teetering, tottering bundle, oddly enough, against all reasonable expectations, failed to dive sideways and untidily disperse itself into four pieces around the floor of the pond. With wild jerks and much shouting from the two of us, the bundle settled itself according to the master plan, liner underneath, then the two bricks, and the pump sitting on the bricks. My wife was astonished, as was I&emdash;though I showed it less. We slid the string out, and marveled at Irish planning with its excessive reliance on luck saving the day.


Making the bog:

I had plenty of liner left over, enough for the bog and stream, and Lake Superior. I began digging at the high point of the garden, finding quickly that I would need to build a further wall on the pond side to support the bog. There was enough wall stone left over from the rear and side walls. This also determined the shape of the rest of the raised garden, saving me from some of the designs I had been composing in my head. This bog, and the stream from it to the pond, would take up a good third of the space available.

Digging and shaping the bog was familiar work; it was basically a small pond. Here I was able to do something for a second time, like the professionals. Pity I didn't do them the other way around, as I had learned a lot from my mistakes with the liner in the pond. The bog was a much neater affair&emdash;though no one would ever see it once the stones went in.

The digging went easily, as I was moving out soil that I had recently tossed here from the pond, and the lower foot or so I felt I recognized from the earlier excavation for the fence and bamboo. I was looking at the soil with increasing respect the more I learned. It takes, I had read, between 300 to 1,000 years to produce 2.5 centimeters of topsoil. So that's 10,000 years for the 25 centimeters, which is the minimum one needs for healthy crops. Adam came from a handful of Eden, and so ought to have been composed, as is most soil, of 50% oxygen, 33% silicon, 7% aluminum, 4% iron, and 2% carbon. Those 10,000 species of micro-organism in each gram were grateful for the fact that 50% of soil is air and water, which they need to feed and reproduce&emdash;it doesn't look as though it can be much fun in there, but no doubt they see it differently..

What was I doing with this wonderful soil I was digging out? Well, there was no-where on the garden to put it, so I shoveled it into the wheelbarrow and dumped it at the other side of the pond, in the space where the tea-house is to go. This is an Irish principle, of constantly moving things to where-ever is immediately convenient, rather than considering for a while and finding a long term final place for them. Easier to worry about that later. The Irish principle does at least keep one moving on the job at hand, even if it does create rather a lot of unnecessary future work.

Once I was down about three feet and had shaped another attractive grave, I lined the base and sides with sand, folded the liner in place, and then faced a problem. How was I to get the flexible pipe from the pump to spread the water evenly around the base of the bog, and not be crushed by the stones I would be pouring on top of it? I laid an extra layer of liner on the base of the bog first, as added protection, and put the pipe in a circle over it. Then I drilled moderate sized holes in the parts of the pipe that lay on the bog floor. I put bricks beside the pipe all the way around, and laid large stones on top of the bricks. So I had the pipe circling like a tube in an underground railway tunnel. I thought this should ensure that water would pour out more or less evenly through the base of the bog, and the stones I would tumble in wouldn't crush the pipe.

I then washed and carefully spaced a layer of large stones around the bottom of what was to be the bog. These were undistinguished stones I had dug up in the process of building the fence and digging out the pond. Though, as I increasingly came to see, how could one call a stone undistinguished? As time went on, it was the homely local stones that I came to value most and place in the garden&emdash;though I didn't value them enough to dig out the bog again to get at those I had buried.

I then poured bags of drain-tile stones into the wheelbarrow, sprayed water over them and rinsed a couple of times to get the dust and clay off, and then poured them till they filled all the crannies around the first layer, and were packed a foot or so deep. Next came a layer of still smaller stones&emdash;those round tan-colored things people use in hydroponic gardening, which I hoped would be OK--and last came the pea gravel. The job hadn't been as hard as I'd expected, and, lo, there I had myself a biological filter bog. The only small remaining problem was to discover if it would work. Details, details.


The stream and waterfalls

The first artificial fountains and waterfalls were built for those Persian emperors in what is now Iran about 4,000 BCE. For much of the ancient world, west and east, natural springs have had a magical or numinous quality, as well they might. Water is where we started from: our oldest home. We left the sea only when we grew a bag of skin to carry our liquids within us. Often the springs of our ancestors were decorated with statues of gods or goddesses, and the names of many of the world's rivers derive from ancient divinities. The great age of fountains and artificial waterfalls in the West was the Renaissance. Look at all those Roman fountains.

The more one looks at water moving, the more magical it seems. Think of Leonardo, watching and watching, and trying to draw the shapes it fell into. If we see it little, or attend to it carelessly, then the magic is not so obvious. Flaubert put it rather better: "Everything is interesting, provided you look at it for long enough." I heard of an old woman who had lived all her life in a small village in the middle of England. A grandson with a new car discovered that she had never seen the sea. The next Sunday he arranged to take her to Blackpool, on the Lancashire coast. He walked with her out to the end of the pier, and the old woman stood in silence watching the sea for ten minutes or so, then turned to her grandson and said, "Is that all it does?"

I'm afraid I fell into the worst Irish habits building the stream. Instead of cutting a clean piece of liner from the remaining acres of the stuff, I decided to make do with various pieces left-over from trimming around the pond, overlapping them so the water would flow merrily from one to another before becoming the final gurgling waterfall.

I started at the pond end, and dug the soil high behind the layers of stones already in place where the main waterfall into the pond was to be. Then I shaped a groove for the stream to go from the bog to the pond, and lay the irregular pieces of liner over it. Well, what a mess. But, it was show time. Everything seemed ready. I couldn't put it off any longer; there was nothing else to do but plug in the pump to the long and sturdy extension cord I had trailed from the house along the fence. My wife did the ceremonial job, stood back and&emdash;nothing happened.

I don't know what I expected immediately. I thought I'd hear the pump, but there was nothing; no sound, no motion of water in the pond to suggest it was working. What do I do now? I had not reckoned how long it would take to fill the bog, but then it filled, and overfilled, and the water came pouring murkily into the stream, and into the pond. The murk seems to have been due to a couple of bags of pea gravel I hadn't washed adequately. Fortunately, the water cleared in a few minutes, leaving me, though, with a rather soiled pond. Here it is running cheerfully, if a little lopsidedly:

The next morning I got up to find the water level had dropped significantly. I poured in more from the tap. The next day it was down again. There must be a leak. It didn't take long to find that the water was finding every little gap in the liner along the stream, cunningly flowing back under the layers I thought were carrying it onwards. I had built a series of short stretches with slight backward slopes, so that even if the water stopped running there would be water to protect the liner from the sun. There were also three small waterfalls; one from the bog, another half way along the stream, and then the final fall to the pond. The main leaking culprit was the area of flowback just below the bog. ß

So I did what I should have done at the beginning. I threw aside the old pieces of liner and cut a generous chunk of clean liner from the acreage so far untouched. I lay down the single new piece, tucking it far under the piece that came out from the bog, and leading it to the very edge of the falls into the pool. The next day, I had no discernable loss of water from the pond. Now I could start laying stones over the liner, to pretend that this elaborate combination of technologies was a part of the natural world.


The attack of the raccoons

Having got the pump working, some tall plants on the marginal shelves, oxygenaters on the bottom, and floaters on the surface, I could look forward to fish bringing further life to the pond. I spent a full day laying out the plants, adding gravel to the bog, netting leaves or bits of grass from the pond surface, and basically getting it ready for the new tenants who were due the next day. I went to bed, tired but happily anticipating the golden flash of fish among the green. I came down the following morning to admire my handiwork, but found instead that my cosmetic work had been wrecked by those incorrigible desperadoes of suburban gardens, the raccoons. The water lily had been upended and tossed off its base into the bottom of the pond, and the floating plants were in tatters, having been chewed and mostly discarded by these less than fastidious goumands. The tall marginal plants had in some cases been toppled and in some sampled for their potential gustatorial delights; a test they had clearly failed.

How could I put fish into the pond if raccoons were likely to have a nightly swim and frolic, and make a meal of little swimming goldfish? What to do, again? I asked neighbors, each of whom had a suggestion. One had heard that pepper kept them away. I bought a couple of large tins, and spread it all around the pond. It did seem to deter the raccoons, but it deterred me too. A visit to the pond was followed by a sneezing bout. And I couldn't keep adding pepper&emdash;what would the place be like after five years of it?

Others recommended rigging up a small electric shock wire, which seemed a bit much in an area full of cats, and children. My elder son, ever practical, suggested land mines. "They'd learn after the first few." But as Canada had taken the lead in getting signatories to the international land mine treaty, I didn't feel this was the way to go. As a stopgap, I bought a pile of eight-foot long one by two pieces of wood, and a roll of chicken wire. I made three large frames that would reach across the pond, stapled chicken wire to them, and lowered them over the pond each evening. I have heard something, I assume raccoons, jiggling them at night, as I lie anxious in bed. And on quiet nights the clacking of the bricks I use to hold them down as something shakes the frames. They have held for a number of months now, but I'm not eager to have to cover the pond each night for the rest of my life, and uncover it in the wet or snowy mornings.

We used to have a luxuriant vine that grew around our back deck, and families of raccoons would come each fall to have dinner on the vine as we had dinner inside at the table. The vine turned out to produce grapes with a not very pleasant taste and with a tough and bitter skin. A friend loaded himself with tons of them one sunny fall and made gallons of a rather nasty wine. So we were quite happy to share with the raccoons, who clearly found them exquisite. They enthusiastically slurped their way along the vine. I admired their beautiful and powerful articulate black hands. Once I was in our basement with our children and heard a slightly odd noise at the cat's dish upstairs and then unfamiliar sounds on the steps to the basement. I opened the door to see the big mother raccoon leading her brood of four or five babies down the steps. I stood in the doorway of our basement playroom, calling the children to see, as the raccoons trooped past, eyeing us casually and fearlessly. The back door was open, and the family trotted out as casual as you like.


Go to Part IV

Return to Japanese Garden Introductory Page

Return to Home Page