International Rainwater Catchment Systems Association
International Rainwater Catchment Systems Conferences
  Next conference
  1st, Hawaii
  2nd, St Thomas
  3rd, Khon Kaen
  4th, Manila
  5th, Taiwan
  6th, Nairobi
  7th, Beijing
  8th, Tehran
  9th, Petrolina
  10th, Mannheim
  11th, Texcoco
  12th, New Delhi
  13th, Sydney
  14th, Kuala Lumpur
  Join IRCSA
  IRCSA Board

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

Section C: Design

Paper C.9

Analysis of Rainfall Patterns for the Design of Rain Catchment Water Supplies an a Tropical Wet/Dry Season Climate

Guenther E. Seidel, D.I.C.
Rural Water Supply Engineer
Department of Health
P.O. Box 3991
Boroko N.C.D
Papua New Guinea


In Papua New Guinea extensive rainfall records are available but they are not computerized. A method was needed which allowed a sufficiently thorough analysis yet kept data coding at a manageable level.

A two phase approach was adopted: In phase one monthly rainfall totals for 38 representative stations and continuous record lengths of around thirty years were analysed to yield probability distributions of the occurrence and severity of dry periods. The whole country was then zoned into seven distinctive dry period rainfall regimes. Phase two of the analysis consisted of numerical simulations of rain catchment supplies using actual daily rainfalls for representative periods for each of the seven zones identified in phase one. Two types of simulation were run: One for standalone systems the other for systems with supplementary topups from external sources.

The results are a map of Papua New Guinea showing the seven zones and sets of design tables for each zone. Tabulated are the percent reliability of a standalone system and the number of topups required, both as functions of catchment area and storage volume.

The computer programmes used could be run on most microcomputers using the CP/M80 operating system.

PDF of full document (16pp, 670kb)

Note: The IRCSA proceedings section is still new and under active management, If you find any problems, ommissions or corrections please contact the administrator so we can put things right.
Top of Page