Q. We live on a river. I would love to plant some interesting things on the bank below our home but with the price of water these days I would love to be able to pump some river water up to do the job. Do you think that that is something we could do without spending a fortune? It would be great to have a soaker system.
A. First, you must have the right to take water from the creek, river,. pond, etc.. This almost always means you need to talk with the US Fish & Game Department, State regulators, and possibly the Environmental Protection Agency (or equivalent agencies for whatever country you are located in.) If you take water from a creek or pond or any other natural body of water in the USA without checking on the legal rights and requirements you can get into a lot of hot water, fast. The fines penalties and restitution costs can be enormous. So before you do anything, start doing some calling around. Be safe, not sorry. If you don’t know who to call, try calling the local County or Parrish Planning Department, they should be familiar with the agencies that regulate water and be able to point you to the right people.
Yes, from a physical standpoint it is not difficult to pump the water. The cost depends on how fancy you make it. My parents had a cabin on a river in Oregon. They simply had a small portable pump that sat on a concrete block and was chained to a tree. One end of a 15′ garden hose was attached to the pump intake, the other end of the hose had a piece of window screen tied around it to create a home-made filter and keep out small fish and junk. The end of the hose with the screen filter was tied to a concrete block and dropped into the river. The pump outlet was attached to a second garden hose, this one was 150 feet long. A long extension cord went from the pump to the power outlet at the cabin. They put a sprinkler on the end of the hose, placed the sprinkler where they wanted water, then plugged in the pump. Simple, cheap. You could easily semi-automate that by simply plugging the pump’s power cord into a timer to turn it on and off.
A fancier system is certainly possible. The pump still needs to be portable in most cases. The pump has to be mounted less than 8 feet above the water level (the closer the better.) You need a pad of some sort to put the pump on, but it is best if the pump can be easily moved, especially if the water level fluctuates in the creek or floods. There is also the possibility of using a submersible pump. A submersible should not sit on the bottom of the stream if there is a lot of mud and silt in the water that would get sucked into the pump. If you have a floating dock or a pier an alternative is to place the pump on it (or hang it below the dock in the case of a submersible pump.) Submersible pumps are often strapped to the side of pier pilings. Be sure to read installation instructions for the pump, many pumps have very specific positioning requirements, some submersibles must be installed inside a special sleeve.
You can get about as fancy as you want- using automatic controls to start and stop the pump and also to open and close multiple irrigation valves. Many irrigation controllers have built in circuitry that will start and stop the pump for you using a electrical relay. If you do it yourself, and you need only something similar to my parent’s small pump you could probably install a pump for around $200.00. The price can go up fast as you get bigger and fancier, $1000.00 is not an out of line figure for a pump system capable of watering an acre or so of yard. The wiring for the pump automated controls is a bit tricky, so most people would want to have that part done by a electrician. How much that costs depends on the length of wire needed to reach the pump. One option to look at when you get to larger irrigation systems is a pre-constructed pump unit. This consists of the pump and all of the needed controls for it pre-installed and pre-tested on a metal frame. You just hook up the pipes and wires to it and turn it on.
You may also need a storage tank for the water, especially if you have a small water supply (like a creek.) That way you could pump a small flow continuously from the creek to fill the tank. Once in the tank the irrigation water would either be pumped out of the tank to the irrigation system by a second pump, or if the tank can be located 30′ or so higher than the level of the irrigated area, you could use gravity flow from the tank. (If you want to use sprinklers the tank would need to be at least 60 feet higher to create enough pressure for a small sprinkler.) The tank will probably need to be a lot larger than you think. Typically they are 5,000 gallons or larger. To find out what size tank you will need you need to determine how much water it will take to irrigate your area. See How to Estimate Irrigation Water Quantity Needed for instructions on estimating your water requirements.
One last word of warning before you start: PLAN FIRST, BUY LATER! Don’t run out and buy an “irrigation pump” first! Most pumps sold with the description “irrigation pump” are designed to operate a single sprinkler on the end of a hose. You need to design the irrigation first, then you will now how much water volume AND water pressure the pump will need to produce. The Sprinkler System Design Tutorial takes you through the process of irrigation system design and finding the right pump size. It’s at http://www.irrigationtutorials.com/sprinkler00.htm