Tag Archives: Hawaii

Poorly Designed Rainwater Harvesting Systems

Poorly designed and maintained rainwater harvesting systems can be more than unpleasant.

As many others did, I built a house in the Puna district of the Big Island of Hawaii in the 1980’s. The inexpensive properties of the subdivisions above Hilo provided an opportunity for home ownership to those who could not otherwise afford to build. The subdivisions were created in the 1960’s and 70’s as agricultural, with little infrastructure, certainly no water source. As everyone else did, I built my own rainwater catchment system, designed based on what everyone else was doing. The county provided “city water” stops along Kamehameha Highway, for drinking water for those on rainwater catchment. All other household water use was provided by the catchment system with little filtering and no real disinfection. UV disinfection was not available for small water systems at that time. 

Many systems were owner built and consisted of a “pool boy” – an above ground swimming pool with a non potable liner. There were some corrugated steel and a few cement or wooden tanks. Many of the roofs were asphalt shingle, causing a bit of a sheen on the water surface during the hot day. A sediment filter prior to the pump was the typical filtration train and, as mentioned, no disinfection. But, no one was drinking it as far as I knew. 

For decades there were no regulations for rainwater catchment systems in Hawaii. Systems were built with not much consideration of public health. Essentially, a large community with no oversight to standards or safe practices. Now, many of these antiquated systems are being contaminated by slugs and snails which have been found to carry “rat lungworm parasite”, a potentially devastating disease. Please see below article.

Water Catchment Systems Need to be Properly Maintained

Rainwater catchment can be a safe, viable alternative to ground water “IF” proper best practices are followed. The industry has grown considerably, along with most states having some type of regulations and permitting.

ARCSA/ASPE/ANSI 63 has been adopted as code by most municipalities that allow rainwater collection for potable use. ARCSA Accredited Professionals are trained and must participate in continuing education in order to keep their accreditation. Designs for permitting are being submitted to Health Departments for plans review. Inspections by county plumbing inspectors during construction of systems is common with bacterial sampling required by some.

It is not the 70s and 80s any longer and rainwater catchment for potable use has hit an all time high here in Washington State. Systems are being designed and installed by professionals that have the training and experience needed for the well-being of their customers. Check with your contractor to be sure they are ARCSA Accredited and know the code requirements. By doing so, you will be assuring that your water source is safe for you and your family.

Rainwater Harvesting and Life on Maui

Maui 2004As some of us living in colder climes hunker down for the cold weather, now is a good time to share an article from Maui Now about green living with rainwater catchment systems.

The article effectively and simply illuminates the benefits of collecting rainwater for either landscaping or drinking water, outlining the components and why each is important for a system that will either supplement or replace city water.

Some folks may find (at least on Maui) that the property they’re interested in purchasing is off grid, with no city water source available. Others want to supplement city water to save money and reduce demand on city infrastructure, decelerating the onset of potential future water shortages.

According to the article, ‘With a rainwater catchment system, you will be able to capture rainwater, divert it to a storage area, save it in a safe and clean place for later use, and then create a system for water distribution.”

RainBank is an experienced rainwater collection system design firm and consults on systems for residential and commercial use. RainBank designs potable and non-potable systems to be used for irrigation, laundry, toilet and wash down facilities. RainBank follows its designs through the permitting process; clients have an advocate to navigate the confusing maze of government entities and regulations. RainBank president Ken Blair is ARCSA AP (Accredited Professional) and IS (Inspector Specialist), both of which require continuing education for certification. RainBank also serves as ARCSA’s Pacific Coastal Regional Representative.