EVS 921:2022

This Estonian standard is applicable to external water supply networks, regardless of the form of ownership, including the water network from the water treatment plant or borehole pump to the external wall of the buildings. The standard is the basis for the design of the water network, the dimensioning of water pipelines and the selection of pumps and other auxiliary equipment, and can be used both for the construction of a new water network and for the extension and conversion of an existing water network.
The standard specifies the functional requirements for the planning, design, construction, operation, maintenance and operation of the external water supply network, and the activities to meet the requirements.
Water treatment includes water intake, water treatment, water storage and transmission (external water supply network / distribution) to the consumer (see Figure 1).
When selecting a water intake water source, follow the relevant legislation and the standard EVS 847-1, when processing water, follow the standard EVS 847-2, when distributing water to the consumer, follow the relevant legislation and standards EVS 921 and EVS 835.