3rd International Rainwater Cistern Systems Conference
Khon Kaen, Thailand - January, 1987

Section B: Planning

Paper B.2

Freshwater Storing by the Karl Dunkers's Method

William Hogland, Ph.D
Janusz Niemczynowicz, Ph.D
Lars-Erik Widarsson, C.E.

In arid and semi-arid regions as well as in some parts of the Swedish archipelago, there are periodical shortages of drinking water. In order to ensure a constant supply of freshwater in these regions there is a need to store water. The Swedish inventor Karl Dunkers has developed three operational systems for the collection, storage and conservation of rainwater. Each of these systems contains storage elements, simple treatment units and circulation facilities. Collected rainwater is constantly kept in circulation through the treatment unit, thus remaining fresh for infinite periods of time.

The Department of Water Resources Engineering is involved in the development and testing of Karl Dunkers's storage systems. Since the technique of storage water according to Karl Dunkers's method is new, several questions about its hydraulic and hydrologic functions must be answered. The method must be adapted to local conditions before fresh water can be produced in a cost-effective manner.

A full-size installation for storing and treatment of rainwater from roofs has been built during the spring of 1985 on the island of Varmdo just outside the city of Stockholm. The storing unit consists of two tanks, 21 m³ each, equipped with an external circulation system. The circulation system consists of circulation pumps, sand-anthracite filters and sodium hypochlorite dosing pumps.

This paper gives a general description of Karl Dunkers's method and presents the details of the research program aiming at testing the hydraulic and hydrologic function of the installation on the island of Varmdo.

PDF of full document available to members (15pp, 510kb)