Category Archives: Residential Rainwater Collection

How-to, Rainwater Catchment, Residential Rainwater Collection

The WISY 4 Step Rainwater Collection System

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4 Step Process - RBEarlier this year, we announced that we are a WISY product dealer.

A rainwater system designed with WISY products requires minimal maintenance and never needs replacing. With the WISY 4 Step system, you’ll never clean a filter basket or a tank again.  Ever.

The WISY 4 step system.

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.

More to come: we will offer an online shopping cart for you to make your purchases. Contact us with questions about the WISY 4 Step System.

How-to, Residential Rainwater Collection

Proper Installation is Key for Rainwater Collection System

Chad InstallRainwater collection systems can be a simple as rain barrels or as complicated as whole house potable usage. Still, proper installation is imperative.

Even with the simplest design, like a rain barrel garden system, proper installation is the key to a successful system.

Screening the roof runoff before it enters your storage is essential for water quality. Organic matter entering your storage will decompose and add an odor and possible discoloration of your water. A simple downspout screen upstream of your storage should suffice for small non-potable systems. For household use systems, gutter screening, so debris does not enter downspouts and conveyance lines, achieves best results. This should be followed by prescreening or filtering for smaller particulate, which can be accomplished by a screen basket placed in a sump on top of cistern. All screening requires inspections and cleaning as needed. A vortex filter is a device that replaces a sump or tank screen, which requires less maintenance and cleaning. These devices are available in downspout application, replacing downspout screens, as well as larger vortex filters that are generally installed before cisterns or sump boxes.

Water that is drawn from the cisterns to pressurization, filtration and use is best taken from mid level in the cistern. This can be accomplished with floating suction. Water in the mid water column is the cleanest water in the cistern. Any particulate in the storage tank is either floating on the surface or sinks to the bottom. In addition, if water entering the cistern is aerated and sent out horizontally, it will not disturb the sediment at the bottom of the tank. The aeration of the water will help keep bacteria to lower levels.

Tight line from downspouts to sumps or cisterns should have a drop of 1/16″ per ft. so as to keep standing water in the pipe. The same holds true for gutters. Standing water, if not aerated and free of particulate, can begin to go sour and not only create more bacteria, but can cause an unpleasant odor. Therefore, conveyance lines should be kept away from direct sunlight, have a gentle slope, and kept clean of organic matter. This may cause more work during installation, but is well worth the time and money to do so.

Wisy products, including a vortex filter, calming device, floating suction, and overflow device will keep your water clean and particulate free for storage. Routing your conveyance lines so they are kept from UV light, sloped, with no bends greater than 45 degrees will help water entering your cisterns as clean as can be with the end use being cleaner safe water, whether it is for potable or non potable.

RainBank is a Wisy product distributor. Contact us using the form below to purchase Wisy products.

Rainwater Catchment, Residential Rainwater Collection

Truths and Myths About King County Rainwater Harvesting

Seattle Waterfront ParkI have been designing and installing rainwater harvesting systems in King County and throughout Washington State for 15 years and am still amazed and dismayed at the misinformation that is presented to the pubic when inquiring about the legality, procedures, and permitting for rainwater harvesting.

TRUTH: Rainwater collection is legal throughout Washington State

Washington State Department of Ecology issued an interpretive policy statement clarifying that a water right is not required for rooftop rainwater harvesting. As described by Washington State Department Ecology, Clarifications of Washington State Rainwater Law Pol 1017 in reference to RCW980.03 & RCW90.54 and the Environmental Protection Agency’s paper on Rainwater Harvesting Conservation, Credit, Codes, and Cost Literature Review and Case Studies

False: Rainwater harvesting is not allowed for drinking water in Washington State.

It is up to each county and city in Washington State to allow for potable usage of rainwater. King, Jefferson, Whatcom, San Juan, Skagit, and Island are counties that currently allow potable use of rainwater for a single-family residence. It is the health department of those counties that are the typical authorities for regulations and permitting.

Here are some resources for gathering information about rainwater collection guidelines in Washington:

As Washington State counties are recognizing the benefits of rainwater collection and the fact that rainwater can provide a viable source of water for potable usage, other counties will adopt RWC as an alternative water source.

RainBank Rainwater Systems is the leader in rainwater collection system designs and installations in Washington State and president Ken Blair is the NW Regional Representative for The American Rainwater Catchment Systems Association (ARCSA). RainBank is committed to helping customers and counties understand the benefits, standards, and policies of rainwater harvesting in order to provide a clean, safe, viable source of quality water.

Seattle waterfront park photo is courtesy of Nicola under Creative Commons