BY DON M. SCOTT, RAILROAD MAN
BY DON HERZOG, MINIATURE PLANT KINGDOM

SHAPING THE ROCKS

Combine two bags of mortar mix, a shovel full of Portland cement, cement coloring (if you want any), and water. Mix well and lay a two inch thick pad where your first course of rocks will go. Push a half-inch diameter plastic pipe a little longer than the width of the pad across the middle of the cement. The pipe will drain any excess water from behind the waterfall into the pond. Sometimes a small leak or rain causes water to accumulate there.

Put the first course of rock on the cement pad and fill any gaps with mortar mix and small rocks. Then put another layer of mortar mix over the rocks you just placed and add a second course. Then add a third, but no more until the following day, and let the edifice dry overnight. The next day, add three more courses (if necessary). Continue until you reach the height where you want the lip and let everything dry overnight.

The lip (it may be one or more rocks) is the most important working part of the waterfall. It must project a particular pattern of water a specific distance into the pond. It also must be long enough to fit securely into the body of the waterfall. When you choose the lip, it is unnecessary to match the rest of the rocks making up the waterfall, especially since most of the other rocks are probably round and the lip must be flat.

In my case, I wanted the train to go under the waterfall so I found two long, rectangular rocks, placed them side by side, and cemented them together to form the lip. Remember also to choose a lip long enough to protrude from the back of the waterfall as a counterbalance, especially if the rock is long or heavy.

To place the lip, pour enough mortar over the last course to accommodate the width of the lip. Place the lip, making sure it is level horizontally and has the downward angle you want. Place, but do not cement, the next rock course. The idea is only to help balance and secure the lip. Brace the underside of the lip with wood and let the cement dry.

The next day, cement a long rock or a series of rocks along the top sides of the lip if you want to direct all the water over its front edge.

PLUMBING

Cut a piece of 2 inch diameter plastic pipe long enough to fit from the rear of the lip rock to 4 inches beyond the front edge of the waterfall body. Glue it into the center port of a "T" fitting. Put a 90-degree elbow in the far right and left corners of the lip rock inside the water deflectors, where the rock comes through the wall. Cut pipe long enough to fasten into the "T" and elbows. Glue the elbows to the "T", making sure the entire assembly lies flat on the lip rock. When you are done, about 4 inches of pipe should extend past the lip rock on the rear of the waterfall body. Let the lip dry overnight, then build whatever additional courses and lips you want to complete the appearance of your waterfall. If you add additional lips, be sure to plumb each as above.

Note: You must plumb the pond with pipe large enough to carry the necessary volume of water for the waterfall and also allow for some expansion. I suggest a minimum pipe diameter of 2 inches for any system using a swimming pool pump. It might also help to add one size to the diameter of the drain and skimmer pipes. It is easy to add a bushing to reduce the diameter if you have overestimated. Remember, every time you add a fall or stream to the waterfall, the pump must supply more water. Not only must the pump size be adequate, the pipe leading to the pump must have a large enough diameter to provide the volume of water the pump will need. If the pump must draw more water than the pipe can provide, it may burn out.

Caution: When gluing pipe, always leave enough excess between the fittings to allow for changes or repairs.

NOW FOLLOW THESE STEPS

1. Two pipes should be sticking up at the rear of the waterfall pad, one from the skimmer and one from the drain. If they are too short, you may need to add some pipe. Cut them to the same height and glue on 90-degree elbows so both elbows are parallel and face the front of the waterfall. The height of the elbows depends on the placement of the intake on the pump.
2. Put a gate valve in each line the same size as the pipe. You may set the handles in any position. The valves will be useful if you have a skimmer and many leaves fall into the pond. If you close the drain valve, all the suction will come from the skimmer. It will help pull leaves and debris into the skimmer collection basket. If a lot of debris has settled at the bottom of the pond or is suspended in the water, close the skimmer valve and the drain will pull better. Otherwise leave both valves open. I use a valve with the brand name "Red and White". It is expensive but, in 27 years, I have never had one fail. Other makes have lasted only a third as long. Whatever valves you choose, open them all the way, then close them down one turn. That will let you close them even if they freeze up after many years.
3. Glue a "T" fitting into the drain pipe so the middle port faces the skimmer line. Glue an elbow fitting the proper distance into the skimmer line facing the drain line. That will allow you to glue a pipe from the elbow into the middle port of the "T" on the drain line.
4. Glue a piece of pipe into the "T". Cut it long enough so you can glue an elbow from the other end to the pump intake. Cut and place a swing check valve into the line. Be sure to look for the arrow showing the direction of flow. The cleanout should be on top of the valve.
5. Glue the elbow to the end of the drain pipe and point the elbow to the pump intake. Be sure it is level.
6. Screw a male adapter fitting into the pump's intake and outflow ports. Use Rectorseal pipe thread compound if it is available. Otherwise, Teflon tape or other compounds will do.
7. On horizontal intake pumps, glue a piece of pipe from the elbow to the intake port. On vertical intake pumps you must make the connection with an additional elbow and short piece of pipe. If you have used oversize pipe, remember to install a reducer bushing to match the size of the intake port.
8. Use whatever pipe and fittings may be necessary to reach from the pump to the filter. Be sure to put the pipe into the filter's intake port. The ports should have labels or arrows for identification. Any swimming pool supply house can help if you have trouble. Also, when piping from the pump to the filter, try to avoid blocking any area or object you may have to access later.
9. Glue a 90-degree elbow to the end of the pipe sticking out over the rear of the lip rock behind the waterfall. Be sure it points down.
10. Glue pipe from the filter to the area directly below the fitting you added in the above step. Glue on an elbow facing upward toward the one you just installed. They should line up precisely because, in a moment, you will join them.
11. Glue a "T" fitting into the pipe. Its center port should face either side of the waterfall. Glue a short piece of pipe into the center port of the "T". The fitting must be level with the ground. Then glue a slip-by 3/4-inch thread reducer bushing into the port facing the rear of the waterfall. Screw a 3/4-inch hose bib into the bushing. It will let you empty the pond. Remember to put pipe joint compound on the hose bib before you screw it in.
12. Put a short piece of pipe into the front port of the "T". If you plan to have only one waterfall and no need to divert the water anywhere else, glue on a threaded male adapter and threaded cap. That will let you tap into the system later if necessary. If you have more than one lip rock or plan to run a stream off the pump, I'll address that later.
13. Glue a 6 inch length of pipe into the "T" fitting. Point it up, in line with the fitting in step 9. Glue on a gate valve with its handle pointing in any convenient direction. I pointed mine out of the way, under the lip rock.
14. Glue a piece of pipe from the gate valve into the elbow you installed in step 9. That could complete your plumbing unless you have use for additional water. If you do, continue on:
15. Glue whatever fittings you may need to extend to other waterfalls, lip rocks, or streams. Use a reducer bushing wherever necessary to service items you must plumb into the system. Remember to put a gate valve wherever you use water so you can control its flow.
16. Call an electrician to wire and power the pump. Avoid doing it yourself; the combination of electricity and water may be fatal.
17. Prime the pump and, if necessary, adjust the water flow. You may also have to cement diversion rocks onto the lip to create a better effect. Then sit back and enjoy the results.