Most of the traditional water data are subject to centralized management, but the rights and interests of the water data are related to water groups, equipment manufacturers, and insurance companies. Then whether the data is tampered during transmission and storage has become a challenge to stakeholders. In view of the above problem, we propose a method for the implementation of intelligent water Blockchain as a Service (BaaS) according to decentralized, unforgettable, and traceable Blockchain technology, avoiding unreliable water data. In addition, we expound the key technologies of BaaS, including the BaaS service architecture, the distributed ledger data model and the Merkle binary tree verification model of health data from intelligent water meters, as well as double buffer queue and Blockchain-based multiple access nodes.