For best results, use the Chrome or Internet Explorer browser on a desktop computer (mobile phones and Firefox or Safari browsers are not recommended). Have your current NTPUD Water/Sewer bill in-hand. Use the Calculator below to calculate your monthly water for year one. This model is applicable to single-family, fire, or irrigation accounts. If you do not see your water base rate, please call the NTPUD at (530) 546-4212. Refresh this page to calculate another bill.