Municipal water supplies vary in static pressure from very low to very high (150 PSI is the highest we've come across). For these supplies, we recommend filling with an approved BWT delivery item that has a built in regulator to drop the static pressure at the connector down to 10 PSI. If the municipal supply static pressure is above 90 PSI, we recommend a brass regulator upstream to knock the incoming pressure down. If a municipal supply has a very low pressure (<20 PSI) please contact us to discuss delivery item options. Care needs to be taken to ensure that you are matched up properly (you don't want to feed 10 PSI into a 20 PSI regulator).