Rainwater catchments in rural Alaska have the potential to produce high-quality water and high quantities of water for household use

Abstract

Rainwater collection is a common source of household water in developed and developing communities where treated on-site water is not available. Although rainwater catchment has been practiced for generations in rural Alaska communities, there are little data available on the quality and quantity of rainwater resources. Forty-eight rainwater samples were collected from nine communities in Alaska over 2 years. Samples were tested for physical water quality parameters, metals, and bacteria. Characteristics of household catchments were recorded. Rainwater quantity in two communities was evaluated. Overall, high-quality water was observed in rain catchments, with average total organic carbon (TOC) and turbidity being lower than or equal to those values in other published rainwater studies. pH was consistently low. Over 80% of samples were below the United States limits for metals and met international microbiological water quality standards. However, variation was observed between households, communities, indoor/outdoor bacteria samples, covered/uncovered storage containers, and over time. The quantity of rainwater available for catchment could supply 17-40% of annual household water and is projected to increase in future decades according to Alaska climate models. Best practices are recommended for rural Alaska communities to maintain the naturally high quality of rainwater and take advantage of large quantities of rainwater available on-site.