Electric rain water pump options

When looking at possibilities for electrically-powered pumps, I encountered several options that I want to remember in case I decide to add an electric pump to my rain water system.  There are several types of pumps, but I haven't explored what is presently popular for the actual part which moves water.

What I did take note of is that one type of pump assembly would be convenient for many situations:  A demand pump or on-demand pump combines a pump with a pressure cutoff switch.  The pump will automatically turn off when its output side has more than a certain pressure, such as 30 or 40 PSI (pounds per square inch).  When connected to a hose or watering system, this allows the pump to turn off when water is no longer needed or when the pump is moving water faster than it can drain out.  A diaphragm tank (because there is a flexible diaphragm which uses pressurized air to push water out of the tank) can hold some pressurized water, so a more constant flow of water can be provided.

However, a pressure cutoff switch only controls what is happening on the output side of the pump and does not protect against what is happening on the input side.  A low water cutoff switch or float switch can turn off the pump when the water level in the rain barrel gets too low.  That protects the pump from trying to pump air, or pumping dry.  A float switch can also be used to stop a pump when a destination barrel is full.

When it rains, it sometimes pours

I've decided to catch the rain from the drainpipe by using barrels with a large open top, so I know that I'll be able to get the first 50 gallons of a sudden cloudburst.  Well, 50 gallons per barrel if they're empty.  I have some 20-gallon barrels that I'll also be connecting in the system, and figuring out how to connect them has been fun.

While I'd like to have two-inch pipe running everywhere, it looks like it will be more practical to feed the extra barrels through a garden hose and 1¼" sump pump tubing (from my overflow pipe).  Obviously this will work better if the rainfall is a trickle rather than a downpour.

So I was wondering how quickly the rain falls... there was a light rainfall yesterday, so let's see what the rate was.  The local National Weather Service office is in Chanhassen, Minnesota.  No rainfall info.  And it says "The weather observations depicted here are not official, and are not quality controlled. For the nearest official observation, check out the data from Flying Cloud Airport in Eden Prairie."  Well, I can understand why the weather office's weather readings might not be official, but it just doesn't seem right.  OK, off to the airport.

During that light rainfall yesterday, there was one hour with 0.14 inch of rain, one hour with 0.05, and several hours at a lesser rate.  Good, that was a nice trickling rate, so collection should work fine with days like that.

When there are brief burst of sudden rain, I should be able to catch much of it also.  The barrels will all be connected together at the bottom, so if the system is half full, each collection barrel can handle about 25 gallons of water at once before overflowing into the 1¼" tube.  The water can then trickle into the other barrels through the bottom hose during the time between cloudbursts.

I'm hoping that will work well enough.  In case I need more capacity, I will have the plumbing designed so I can add more connections.

Keep the critters out of the rain barrel

The openings into a rain barrel system need to be covered to keep out animals.  Some "hardware cloth" coarse screening will keep out most rodents, and many people also use mosquito screen to keep out smaller insects and debris.  Some people use mosquito control tablets to kill the larvae.  Some people put fish in the barrel to eat the insects, although if you have to winterize then the fish is something else to deal with.

However, a little hardware cloth won't solve all critter problems.  (I couldn't find the original source of the bear, merely references to Colorado)

Remember your air vents

I've seen some sketches for rain barrel systems where the designer forgot to supply an air vent.

A bottom-filling sealed barrel won't hold much rainwater if air can't get out of the barrel.  Add a vent to the top, and remember to have the vent opening be higher than your diverter or collector barrel.

A sealed barrel system which fills near the top can also encounter problems if air can't also escape easily through that top pipe.  If you have a two-inch pipe from the diverter, and a two-inch opening into the barrel, you might be fine most of the time because usually there isn't more water than that.  As long as water can flow most of the time there will probably be more than needed to fill the barrels.

Remember to let the air escape so water can flow.  That is also the principle behind the drain-waste-vent (DWV) system that is probably in your house.  Any place where liquid is supposed to flow also needs an air vent behind and in front of it, so the liquid can flow downhill without fighting the air pressure and so the liquid won't create air pressure which will cause problems.

It's a magical wrench

Yay!  My bung wrench arrived!
When making (or cleaning) rain barrels, if you want to open the two-inch bungs on barrels, the tool for the job is a bung wrench.  I chose a plastic wrench instead of metal because I expect I'll have little enough use for it that it will last a long time.

Bungs have two kinds of thread
When you're tinkering with the barrels, be aware that most of them have two different kinds of bungs.  The threads on one bung are hydraulic buttress threads (wedge-shaped in cross section), while the other bung uses National Pipe Thread (NPT) -- also called NPS.  Some people call NPT a "fine thread" and buttress a "coarse thread".  You may be able to identify a sealed bung's type by reading labels on the bung plug (BUTTRESS, NPS or NPT).

That also means that you can screw a two-inch-wide NPT pipe fitting into one of the bung openings, but not the other.  But also keep in mind that bung plugs are available with 3/4 inch NPT knockouts in the center, which offers another way to connect pipe to a barrel.

CISTA: A taller rain barrel shipped in a smaller package

Although it's not on the market yet, architect Carolyn Moss came up with a different design for rain storage.  It's not shaped like a rain barrel.  CISTA is designed to be shipped as several U-shaped sheet metal pieces, brackets, and a 100-gallon bladder.  The brackets are bolted to a building, the metal sides mount on the brackets above each other to form an eight-foot-tall tank, and the bladder is supported inside. Because the pieces can be nested or folded for shipping, they take less space until installed.

It's designed to be installed a little above ground level, so a planter underneath can be used to cover the rain tank with climbing vines.  It looks pretty, of course.

Source: Eco Innovation | EcoLiving

How can I hide or decorate a rain barrel?

Some of my barrels will be white plastic, and I'd like to have something less stark.  I'm open to suggestions.

Let's see...

First I found some barrel covers.  Umm...  They're covers for quarter horse barrel racing.  Zebra striping or blue camo is a little bolder look than I'm after.  That's hardly surprising, as these are supposed to be visible to the racers.



Well, a pretty sunflower.  That's more of a decoration than a disguise.  These are pretty, but then everyone's an art critic.  There are any number of ways to make a barrel slipcover or paint a barrel.  Or to have it painted, depending upon your talent at painting a rain barrel.


My talent at painting is about right for the leaf stencil spray painting method.  Spray a coarse background pattern on the barrel, then use various leaves and small branches as stencils to create natural patterns across the barrel.




A wooden container is an interesting alternative.  Pick your favorite wood and color, and build a barrel-sized box.  I suppose that could also be done with bricks if you prefer brick walls.

Speaking of wood, a wooden lattice was my first thought.  I see that a nearby hardware store has prebuilt lattice panels that are three by four feet, which seems about right.  But they'll cost more than inexpensive barrels cost.  A compromise is to get 4 x 8 foot lattice panels and make smaller panels from those.

Rain gutter and downspout terminology

I had to look up what to call some of the pieces involved with gutters.  From top to bottom, here is a glossary of some terms:

• Rain deflector:  Not actually part of a gutter but rather it is a metal guide which is installed on the roof over a door to guide water sideways and thus reduces water falling over the door.  Often not needed over a gutter system.
• Drip edge flashing: Metal roof edge which extends from under shingles.  Guides water away from edge of shingles.  Might be considered part of the roof.
• Fascia board: Board running along the ends of the rafters at the edge of the roof.  The gutter is often attached to it.
• Splash guard: A baffle which raises the edge of a gutter, to divert the flow of water into the gutter. Often needed at an inside corner due to the water flow from the corresponding trough where two roofs meet.
• Gutter leaf guard: A screen or other device over the gutter to block most leaves from entering the trough.
• Hangers: Brackets that support the gutter.
• Rain gutter, gutter, or eaves trough: The horizontal trough which captures rain water below the edge of the roof.
• Drop out or outlet tube: Connector for the top end of a downspout.  Short tube which is sealed to the edges of a hole in the gutter which has been cut for the tube.
• Leader head, conductor head, or rainhead: A decorative box to collect rain water from gutters and guide it down a downspout.  Used instead of an outlet tube.
• Downspout strainer: A wire mesh or grate at the top of the downspout to block debris from flowing down the downspout.
• Downspout: The vertical tube which carries water downward.
• Downspout strap: Metal straps which hold the downspout against the wall.
• Offset: Elbows used to route a downspout around an obstruction on the wall.
• Downspout diverter: A device to divert water, automatically or manually, between a rainbarrel and downspout.
• Elbow: Often the bottom of a downspout has an elbow which sends the rain away from the building, either away from the wall or to the side (probably toward the corner of the building).  Often a length of downspout, hinged trough, or other device is used to carry the water further from the building.
• Splash block: A concrete pad, masonry, or other device on the ground to protect the ground from the force of water falling from a downspout.