TY - JOUR
T1 - Robust rainwater harvesting
T2 - Probabilistic tank sizing for climate change adaptation
AU - Lash, Daniel
AU - Ward, Sarah
AU - Kershaw, T J
AU - Butler, David
AU - Eames, Matthew
PY - 2014/12/10
Y1 - 2014/12/10
N2 - Rainwater harvesting (RWH) systems are increasingly being implemented in buildings. It is common in the UK for simple RWH tank sizing methods to be utilised, and these do not consider future climate change. This paper describes the development of a tool, which integrates elements of basic and detailed sizing approaches from the British Standard for RWH, with the latest probabilistic UK Climate Projections data. The method was initially applied to the design of a university building in Cornwall, UK. The methodology utilises 3,000 equi-probable rainfall patterns for tank sizing for each time period. Results indicate that, to ensure that it is ‘likely’ that the same non-potable demand could be met in 2080 as in the present, a tank 112% larger would be required. This increases to a 225% over-sizing for a ‘very likely’ probability of meeting the same level of non-potable demand. The same RWH system design was then assessed for three further UK locations with different rainfall characteristics. From these assessments a simplified method was developed to enable practitioners to size RWH system tanks for current and future climates. The method provides a new approach to meet present and future non-potable demands, while preventing excessive over-sizing of tanks.
AB - Rainwater harvesting (RWH) systems are increasingly being implemented in buildings. It is common in the UK for simple RWH tank sizing methods to be utilised, and these do not consider future climate change. This paper describes the development of a tool, which integrates elements of basic and detailed sizing approaches from the British Standard for RWH, with the latest probabilistic UK Climate Projections data. The method was initially applied to the design of a university building in Cornwall, UK. The methodology utilises 3,000 equi-probable rainfall patterns for tank sizing for each time period. Results indicate that, to ensure that it is ‘likely’ that the same non-potable demand could be met in 2080 as in the present, a tank 112% larger would be required. This increases to a 225% over-sizing for a ‘very likely’ probability of meeting the same level of non-potable demand. The same RWH system design was then assessed for three further UK locations with different rainfall characteristics. From these assessments a simplified method was developed to enable practitioners to size RWH system tanks for current and future climates. The method provides a new approach to meet present and future non-potable demands, while preventing excessive over-sizing of tanks.
KW - adaptation
KW - tank sizing
KW - climate change
KW - probabilistic
KW - rainwater harvesting
KW - resilient
UR - http://dx.doi.org/10.2166/wcc.2014.080
UR - http://www.iwaponline.com/jwc/up/jwc2014080.htm
U2 - 10.2166/wcc.2014.080
DO - 10.2166/wcc.2014.080
M3 - Article
SN - 2040-2244
VL - 5
SP - 526
EP - 539
JO - Journal of Water and Climate Change
JF - Journal of Water and Climate Change
IS - 4
ER -