Tag Archives: potable water

Residential Rainwater Collection

How to Achieve Potable Harvested Rainwater with UV Disinfection

file0002019685404UV disinfection is the most common method used in residential rainwater collection systems.

UV light is generated by  supplying voltage across a mixture of gas, causing a discharge of photons, disrupting the DNA of microorganisms which prevents them from reproducing.  If the microorganism cannot replicate, it cannot infect, so viruses, bacteria, Cryptosporidium and Giardia cyst threats are effectively reduced.

A residential UV system typically consists of a power supply (ballast), a UV lamp housed in a Quartz sleeve inside a stainless steel chamber. The flow is directed close to the UV light while passing through the chamber. Effects of turbidity or clarity of the water before entering the chamber must be reduced by proper filtration upstream. Sediment and carbon filtration is used to reduce solids and solution contaminants, which can reduce the effects of UV disinfection. Filtration and UV bulb most be routinely changed in order for all to work effectively. It is recommended to follow manufacturer’s instructions closely, and filters should be changed out as needed.

Some UV systems offer an alarm or sensor with solenoid shut down if the UV system is not working properly. A class “A” UV is the only system considered to purify water that has NOT been deemed “safe to drink”, therefore caution is recommended in the use of a class “B” filter which maybe more tempting to use because of price. The difference between the two is the dosage of the UV light; the lower dose is not as effective in disinfecting. If a more advanced filtration system is used prior to disinfection, you can increase the effectiveness of the class “B”, but caution must be taken for proper results.

UV disinfection provides a relatively low cost, dependable, efficient, chemical free method of water purification that the homeowner can operate to disinfect his or her water supply.

With proper design, installation, and maintenance, clean, safe, and dependable potable water can be achieved from UV disinfection and rainwater collection.

Rainwater Catchment

Where Does a Rainwater Collection System Begin?

gabled houseA Rainwater collection system begins at the roof and ends at point of entry or use.

A well designed rainwater collection system considers what type of roofing material is to be used as the collection surface and what environmental hazards may be present in the surrounding area.

For instance, collecting rainwater for potable usage from a roof adjacent to a stockyard would not be a good idea, for airborne particulate from fecal matter can land on the roof.  Additionally, collecting from a roof near an interstate could have petroleum deposits. Cedar is poisonous, therefore should not be considered for collection for a potable system. Check with the manufacturer of any asphalt shingle type roofing for possible contaminants used in manufacturing.

It is recommended that a “raw water” sample be taken from the downspout and tested for contaminants before construction of a potable system.

Metal is the best choice of roofing material for collecting rainwater for potable usage, however clay, ceramic tile, fiberglass, and plastics are all compatible with collecting rainwater for potable use. Other materials can be considered if not used for potable usage or if carefully evaluated for safety.

“Gabled Houses” courtesy of duron123 / www.freedigitalphotos.net

Do you have more questions about your rainwater collection system?  Contact us!

Rainwater Catchment

Change Your Way of Thinking About Rainwater Collection

Orangutan in The Rain (c) Andrew Suryono, Indonesia, Entry, Nature and Wildlife Category, Open Competition, 2015 Sony World Photography AwardsCollecting the rain makes better sense than complaining about it. Whether you collect it in rain barrels or your storage needs require larger cisterns, rainwater collection and use has a host of benefits. Here is why you should change your way of thinking about rainwater collection:

Rainwater can be a clean, safe, reliable source of potable and non potable water. Rainwater is relatively clean to begin with and if collected, conveyed, stored, filtered and disinfected properly, it can meet the needs of small scale watering to whole house potable use.

Rain barrels can collect water inexpensively for small watering needs, with down spouts being diverted to a rain garden when full, as well as during the rainy season.

Larger cisterns can collect water all winter long to have a large volume for irrigation needs during the summer months. If collected water is pressurized and filtered, it can be plumbed into toilet facilities and laundry to supplement city water usage. If filtered and disinfected, whole house potable usage can be achieved whether large cisterns are used for year-round use or as small storage as a supplement to city water.

So, instead of saying “DARN RAIN!!!!”, consider changing your way of thinking about rainwater collection.

Orangutan in The Rain (c) Andrew Suryono, Indonesia, Entry, Nature and Wildlife Category, Open Competition, 2015 Sony World Photography Awards