In English "rede pública de abastecimento de água" is "mains water" or "main water system". So here I'd just say:

due to mains water system leaks
OR
due to leaks in the mains water system

HTH

Here are some examples:

WB+AD Morgan | FAQs | Finding water, drilling boreholes, water ...
Current water supply regulations dictate that there must be protection against backflow into a mains water system. This can be achieved by the following ...
www.wbadmorgan.co.uk/info_faq.htm

- DUST CONTROL WHEN USING CONCRETE CUTTING SAWS
The mains water system does not have this limitation but portability is restricted ... Mains Water System This system is essentially the same as the tank, ...
www.aplant.com/safety-topics.aspx?id=1727

Electricity, Gas & Water Supplies
This is filled from a ground tank by an electric pump, the tank being filled by tanker or the mains water system. Mains water is sometimes intermittent and ...
www.projectay.co.uk/living_electricity.htm