Water Distribution Networks (WDNs) are key infrastructures for water supply for domestic, public and industrial use. Efficient WDN monitoring is essential to have a sustainable and reliable service, especially in the critical scenarios of water scarcity exacerbated by poor water infrastructure maintenance. Water operators are distinct from the water utility itself, and are responsible for the deployment and management of sensors. This generates a fragmented management structure, especially in areas where multiple operators share different parts of the WDNs. In this context, trust represents an essential challenge. Since each operator manages their own sensors and data, there is no unified view of the entire system. This fragmentation can cause issues, especially when one operator needs to route water through infrastructure owned by another. Here, we propose a trustworthy water network monitoring framework based on blockchain and specifically on DeLoRaN, a decentralized network model built for LoRaWAN environments. By decentralizing the sensor management and enabling verifiable logging, DeLoRaN presents a useful tool for smart water networks in multiple independent operators.