Water supply control station (Estación de Muestreo y control de Aquas Urbanos), Madrid

In some places on the streets of Madrid, you can meet vintage columns for monitoring the pressure and quality of tap water (Estación de Muestreo y control de Aquas Urbanos). At the beginning of the century, samples were taken, of course, manually, now in these boxes, more reminiscent of safes, there is electronic equipment that transmits data to the city's water management center.