Not necessarily. MDPE and HDPE pipes can now be manufactured with a diameter of 2500 - 3000mm. Therefore any size from around 20mm upwards may be used for water. E.g. here is a nice example of 1200m SDR 11 PE pipe from Agru as used in a project in Australia http://www.agru.at/en/solutions/agruline/water-supply-system-for-water-storage/
Published by Mark Jeruzal, Consultant (PE pipe resin production, additives + application) at Mark Jeruzal
Not necessarily. MDPE and HDPE pipes can now be manufactured with a diameter of 2500 - 3000mm. Therefore any size from around 20mm upwards may be used for water. E.g. here is a nice example of 1200m SDR 11 PE pipe from Agru as used in a project in Australia http://www.agru.at/en/solutions/agruline/water-supply-system-for-water-storage/