This paper analyzes economic and social factors as determinants of water saving activities in two Land Improvement Districts (LIDs) in Shiga Prefecture, which have contrasting approaches to water resource conservation. One LID with a volumetric pricing system succeeded in establishing water saving activities at the village level. Villagers had a keen awareness of water conservation and cooperated in water monitoring activities. This may be attributed to the volumetric pricing, as well as to the social structure of the LID as a federation of affiliated village communities. A subsidy from the prefectural government acted as an additional encouragement to water monitoring activities. The other LID with an area-based pricing system was characterized by its top-down approach to saving water, reflecting the LID’s characteristic as a technocratic water-providing agency in addition to a discordance between irrigation blocks and existing village communities. These facts suggest that, in order to achieve sustainable conservation of water resources, economic measures such as volumetric pricing have to be complemented by a collective action based on self-governing village communities.