| Building your own waterfall can be a rewarding | | | | you will have fittings, bends and restrictions in |
| experience however dealing with water can be | | | | your plumbing to have it reach from the pond up |
| tricky so you must arm yourself with as much | | | | to your top bowl so this will also increase the |
| information as possible in order to build something | | | | head pressure. In larger applications the number of |
| that you will be happy with. | | | | bends in the pipe, length and fittings being used |
| Minimum flow rates | | | | are all calculated to determine the exact head loss |
| For every inch of width of your waterfall you | | | | for the water to reach its destination. For smaller |
| should have a minimum of 100 to 150 gph (gallons | | | | applications like your waterfall this calculation is |
| per hour) of water supplied by your pump. | | | | unnecessary. When building your plumbing from |
| Example waterfall: if you want the top bowl in | | | | your pond to the top of your waterfall try to use |
| your waterfall to have a 10 inch wide area where | | | | as few fittings and bends in the pipe as |
| the water rolls over and down your waterfall, you | | | | reasonably possible. Especially try to avoid having |
| would need a pump that can supply 1000gph. | | | | fittings back to back like two or three ninety |
| Additionally you need to understand how pumps | | | | degree bends in a short section of pipe. Fittings |
| are rated to ensure that you get the desired | | | | and bends in short succession because more head |
| effect that you are looking for. There is an | | | | pressure than the same number of fittings spaced |
| efficiency loss in the movement of water through | | | | out further. For simplicity do not calculate the |
| pipes and you will need to account for this to | | | | number of fittings that you will use to build your |
| make sure that your waterfall receives the water | | | | waterfall, but instead oversize your pump by a |
| flow it needs. | | | | minimum of ten percent. |
| Pump ratings and Head loss | | | | Now the whole plumbing equation together |
| The maximum rating for your pump, say | | | | If you have a 10 inch waterfall and a lift of five |
| 1000gph, refers to a pump with zero head | | | | feet, and you account for 10% additional flow |
| pressure. Head pressure refers to the weight of | | | | being lost in the fittings and pipe run you would |
| the water that the pump is lifting and pushing. If | | | | conclude the following. |
| the pump has to lift the water a long way it will | | | | 1000gph at a head pressure of five feet will be a |
| produce less gph. Simplified, the pump will have a | | | | pump advertised with a higher flow rate like |
| rating that refers to the amount of vertical climb | | | | 1250gph, again referring to the zero head |
| the water will need to make. It will supply a chart | | | | pressure. To account for your fittings you would |
| in the pump specifications which states the zero | | | | need 10% more flow, or another 125 gph more |
| head pressure gph, but also the gph to expect | | | | than the pump rated for 1250 gph. This means |
| with one foot of vertical lift, or two feet of | | | | that the minimum pump rating you would consider |
| vertical lift, or five feet of vertical lift and so on. | | | | would be 1375 gph. Round this number up to |
| Fittings cause head loss also | | | | 1400, or maybe even 1500 gph rating as pumps |
| Another factor in this equation is fittings such as | | | | are typically sold in increments of flow rate and |
| ninety degree elbows, forty five degree elbows, | | | | you most likely will not find a 1375 gph pump. |
| and bends in the pipe or valves also will increase | | | | The reason that you need to consider this at this |
| the head pressure. A pump that has to lift the | | | | stage is because you need to determine what |
| water one foot, but also through a series of four | | | | size of pipe to run in your waterfall form from |
| or five 90 degree elbow fittings will have | | | | the pond to the top bowl. If you have estimated |
| significantly less gph than a pump pushing through | | | | the flow rate that you will need to accomplish the |
| a straight run of pipe. | | | | scope of the waterfall you are planning you can |
| The height and width of your waterfall will | | | | find the pump that you will need to accomplish |
| determine your pump requirements | | | | this from your local hardware or pump supply |
| For this reason you need to determine how high | | | | store. The type of pump best suited for most |
| your pump will need to push the water to reach | | | | DIY waterfalls is a submersible pump. It will need |
| your top bowl and also how wide you want the | | | | to sit directly in your pond and as a result a black |
| spillway in your top bowl to be. This will give you | | | | pump is better than a light colored one which will |
| an idea of what size pump you need. Assuming | | | | be highly visible. It is possible to use remote |
| the same 10 inch wide spillway and a vertical climb | | | | pumps like what a swimming pool might use but |
| of five feet to reach the top bowl, you would | | | | this will increase the difficulty of installing the |
| need to find a pump that can produce a minimum | | | | plumbing system considerably as well as increasing |
| of 1000gph with a head of 5 feet. This means | | | | the project cost as well. |
| that the label on the pump would likely be around | | | | Once you locate the pump that you will use for |
| 1250 gph referring to the zero head pressure | | | | your waterfall you can now begin to install the |
| rating for the pump with a performance of about | | | | plumbing system as well as consider details like |
| 1000gph with five feet of head. | | | | creating an electrical chase to allow the cord from |
| Calculating head pressure from pipe fittings | | | | the pump to be installed out of sight as opposed |
| It is recommended to take into consideration that | | | | to hanging out the side of your pond. |