Category Archives: How-to

How-to, Rainwater Catchment

Build a Rainwater Collection System – Throwback Thursday

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slimline tanksHere is a series of articles previously published by RainBank, on how to build a rainwater collection system.

The first post in the series focused on how all rainwater collection systems begin at the roof and gutters. Regardless of purpose, i.e. irrigation, supplementation or drinking, debris must be removed before storing rainwater.

The second, third, fourth and fifth posts in the series talked about tank types, tank sizes, how to keep water clean and kinds of filters to consider for your system.

In post six of the how-to build a rainwater collection system series, we cover managing aesthetics so your system fits into your landscaping  design.

If you’re interested in learning about how to install a rainwater collection system, take a look back at these helpful articles.

If you want to continue to read about rainwater collection and harvesting, remember to click the box below, to receive an email when a new post is launched on this blog.  Thanks for reading!

How-to, Rainwater Catchment, Residential Rainwater Collection

4 Step Rainwater Harvesting Systems

construction-370588_640RainBank Rainwater Systems is proud to announce that, beginning June 1st, we will be a dealer of WISY Products and the 4 step system.  A rainwater system designed with WISY products requires minimal maintenance and never needs replacing.

Step 1. WISY VORTEX FILTER

Before entering the tank for storage, rainwater should be both filtered and aerated.  Filtration removes large particulate matter, which frequently both carries and feeds bacteria.  Removal of this particulate matter, along with oxygenation of the water, greatly reduces the amount of harmful bacteria in the tank.  WISY pre-tank filters accomplish both of these tasks, protecting the water quality in the tank.

Step 2. WISY SMOOTHING INLET

While filtration removes most of the sediment and bacteria before rainwater enters the tank, a small quantity will settle at the bottom of the tank.  This biofilm layer is beneficial for the tank and may remove additional bacteria and metals from the water.  The WISY smoothing inlet calms rainwater as it enters the storage tank to prevent the agitation of sediment at the rainwater inlet.  The smoothing inlet also helps aerate harvested rainwater by directing water upward and outward, avoiding disruption of the beneficial biofilm layer and preserving water quality in the tank.

Step 3. WISY FLOATING FILTER

Since all harvested rainwater is filtered before entering the tank, the floating filter should never clog but will instead take water from just below the surface.  Water at this depth is of the highest quality in the tank, because any particulate that enters the tank either floats on the surface or settles to the bottom.  In RainBank designed systems, the floating filter acts more as an uptake point for the pump than a filter; thus, the floating filter should never require maintenance.

The floating filter consists of a polyethylene ball and stainless steel filter and is supplied with a standard 7 foot length of food-grade suction hose.  The nozzle connections are available in 1 1/4″ and 2″ sizes.

Step 4. WISY OVERFLOW DEVICE

To prevent backup in the system during heavy rains, the storage tank should always include an overflow protection device.  The WISY overflow device has a flapper valve, which allows water to overflow but protects water quality in the cistern with backflow prevention and vermin protection.  The overflow device also contains an angled opening to provide skimming of small buoyant debris, such as pollen, on the water surface.

Be sure to visit us again as we roll out our products and services associated to the 4 Step System. If you have questions, leave them in the comments section below, or contact us.

How-to, Rainwater Harvesting Education

How to Keep Collected Rainwater Clean

Gutter screening, first flush devices, vortex filters – which is best suited for my rainwater collection system?

Cottage without gutter screen
Without gutter screen

If you have been following my last few posts, you can start to understand the need to be sure that your collected rainwater is clean before it goes to storage. Keeping it clean will help keep tannins to a minimum, prevent debris from entering your cistern, and will also mean less demand on your filtration and disinfection systems.

With Gutter Screen
With gutter screen

Gutter screens are the first line of defense to keep your collected rainwater clean before storage. It is well worth the expense to purchase quality gutter screens to start with. Typically, an aluminum frame with stainless steel meshing works the best. They are expensive, but will make maintenance of your system much easier. Stay away from the low density foam insert types, they only clog up with debris and turn septic quickly. Light sheet metal type framing for screens tends to bow in the middle from the weight of the water. So spend some money up front and you won’t need to clean gutters.

A first flush device, or vortex filter is the second defense against debris from entering your rainwater system cisterns.

first flush device
First flush device

A first flush device is a vertical 3” or 4” vertical pipe that has a ball inside that will float to the top of the pipe as the initial water fills. When the ball gets to the top of the pipe, it closes off the vertical pipe and allows the water to move horizontally through a “t” and sends cleaner water to the cistern. The water at the cistern should go through a screen basket before entering the cistern for added protection.

vortex filterThe vortex filter is more of a hands-free device instead of the first flush and for most applications, this designer/installer prefers it. The vortex filter works on a centrifugal theory, where the water enters the top side of the filter from the tight line and is directed into a channeled side which swirls the water horizontally, passing through a screen, then towards storage. Residual water along with the debris falls through the center and towards waste. Only occasional cleaning of the screen is needed for maintenance, making this system as hands off as can be.

Things to consider when choosing a pre-screen system are:

  • Are my gutters hard to get at, are they second story?
  • Do I have a large amount of trees that shed needles and leaves to my roof or gutters?
  • Are my downspout lines connected to tight lines which convey water to the cisterns, or do they gravitate into the top of the cistern?
  • Am I willing and able to care for my first flush devices by maintaining their cleanliness?
  • Do I live in an area that is prone to sub-freezing temperatures?   

 If you have questions, or would like a specific topic covered, let me know in the comments.