Van Vugt, M. (2001).  Community identification moderating the impact of financial incentives in a natural social dilemma:  A water shortage.   Personality and Social Psychology Bulletin, 27, 1440-1449.

Abstract:

The moderating role of community identification was investigated in the impact of different tariff systems on domestic water use. Over a nine month interval both consumption and survey data were collected in 278 households in the UK, 203 of which were on a variable tariff (i.e., charges related to use), and 75 on a fixed tariff (i.e., charges unrelated to use). Adopting a social dilemma approach, I expected a fixed tariff to be associated with greater use than a variable tariff, in particular when resources were valuable, and people identified weakly with their community. This hypothesis was supported in both the field study and an experimental study which simulated a natural resource crisis in the laboratory.