Harvesting Rooftop Runoff from RDP Housing in South Africa: A Pragmatic Approach to Supplement Water Supply While Reducing Flooding, Soil Erosion, and Disease

EPA Grant Number: SU833508
Title: Harvesting Rooftop Runoff from RDP Housing in South Africa: A Pragmatic Approach to Supplement Water Supply While Reducing Flooding, Soil Erosion, and Disease
Investigators: Christy, Ann , Ward, Andy
Current Investigators: Christy, Ann , Ward, Andy , Miller, Mathew , Kallio, Rebecca , Kallio, Sara , Childs, Steve
Institution: The Ohio State University
EPA Project Officer: Nolt-Helms, Cynthia
Phase: I
Project Period: June 9, 2006 through July 10, 2008
Project Amount: $9,998
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2007) RFA Text |  Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Agriculture , P3 Awards , Sustainability


In South Africa, millions of people live in poverty and reside in shanty towns. To address this issue, the Reconstruction and Development Programme (RDP) was established to provide housing for impoverished citizens. The RDP has built more than 1.7 million homes but there remains a serious housing shortage. Many of the RDP houses have corrugated metal roofs with no gutters and are built in areas with steep slopes, poor drainage, or high water tables. Soil erosions, flooding, and water borne diseases are problems in these new housing communities. Most residents are impoverished and quickly use their free monthly water supply allotment. Efforts to establish individual or community vegetable gardens are hampered by a lack of resources and inadequate rainfall. The goal of the project is to design a rain water collection unit that will collect runoff from rooftops and then distribute this water for use in flushing toilets and irrigation of gardens.


The project will be conducted by engineering students as part of a capstone design sequence of courses. A collaborative study has been initiated with faculty and staff at the University of Kwa-Zulu Natal (UKZN). In the summer of 2006, the project team visited South Africa. Initially, in Ohio, a portion of a roof will be constructed and runoff collection and redistribution systems will be evaluated. Components that will be designed and evaluated include: (1) the gutter systems and methods to connect the gutter to the corrugated roof; (2) debris, animal, and reptile screens; (3) the size, construction, and elevation(s) to locate the rainfall collection devices; and (4) self-sustaining distribution systems. For safety and practical reasons the collection tanks will not be attached to these concrete block RDP houses. A multitank system that includes an elevated small tank for water to flush a toilet. Excess water will go to larger tanks that supply water for irrigation purposes. Low cost, durability, practicality, and sustainability are key issues that will be evaluated. Following initial evaluation in Ohio, the design team will return to South Africa and a prototype system will be installed and evaluated on several RDP houses, and alternative housing approaches, that are being studied by students and faculty at the UKZN. The reliability and durability of proposed designs will be evaluated using a probabilistic risk assessment methodology. A comparative evaluation of costs for each design will be conducted using a cost-benefit analysis.

Publications and Presentations:

Publications have been submitted on this project: View all 1 publications for this project

Supplemental Keywords:

Technology for sustainable environment, hydrology, irrigation, rain barrels, capstone design course,

Progress and Final Reports:

  • 2006
  • 2007
  • Final Report