Walnut Creek Water Department - Pay Bill, Contact, Address & Services
Everything you need for Casa Medanos Water System — serving 45 residents in Walnut Creek, CA.
45
Residents Served
16
Connections
Mon–Fri 8:00 AM – 5:00 PM
Office Hours
Walnut Creek Water Department Address
Walnut Creek, CA 94596
Local Tip: Street parking near Walnut Creek municipal offices fills up fast before 10 AM. Arrive early if paying in person or drop your check in the after-hours payment box.
Walnut Creek Water Department Contact
Customer Service
(415) 409-4500
Office Hours
Mon–Fri 8:00 AM – 5:00 PM
How to Pay Your Walnut Creek Water Bill Online
Visit the Official Payment Page
Go to the Casa Medanos Water System website. Look for the "Pay My Bill" or "Online Payments" section.
Open Official Portal →Enter Your Account Number
Find your account number on your paper bill (top-right corner). Enter it along with your last name or service address.
Choose a Payment Method
Select credit card, debit card, eCheck, or bank draft. eCheck is often free while cards may have a small convenience fee.
Confirm and Save Your Receipt
Review the total, submit payment, and save or screenshot your confirmation number. Payments usually post within 1-2 business days.
Quick Tip: Payments made before 3 PM usually post the same business day. Weekend and holiday payments process the next business day.
Walnut Creek Water Bill Payment Guide
Complete step-by-step payment instructions, accepted methods, billing tips, and more.
💡 Walnut Creek Insider Tips
Best Time to Call
Lines are shortest right when the office opens. Try calling at 8:00 AM on a Tuesday or Wednesday to skip the queue.
Save on Fees
Walnut Creek accepts eCheck payments at no extra charge. Card payments may add a $2-3 convenience fee per transaction.
Start, Stop, or Transfer Water Service
Start New Service
Moving into Walnut Creek? Contact Casa Medanos Water System at least 3 business days before your move-in date.
✓ Valid photo ID required
✓ Proof of address (lease or deed)
✓ Deposit may apply for new accounts
Stop Service
Moving out? Request disconnection at least 2 business days ahead. You will receive a final bill.
✓ Final meter reading scheduled
✓ Forwarding address for final bill
✓ Deposit refunded within 30 days
Transfer Service
Moving within Walnut Creek? Transfer your existing account instead of closing and reopening.
✓ Same account number kept
✓ No new deposit needed
✓ Processing: 1-3 business days
Report Water Issues in Walnut Creek
Water Leak
Notice water pooling near the street or sidewalk? Call Casa Medanos Water System immediately. Do not try to access the meter box yourself.
Sewer Backup
Call your utility before contacting a plumber. Walnut Creek will check the main line first at no charge if the issue is on their side.
Service Outage
No water? Check with your neighbors first. If the outage is widespread, call (415) 409-4500 for a restoration estimate.
Real-Life Tip: Take a quick photo or video of the issue before calling. It helps dispatch prioritize and gives the crew a head start before arriving on site.
Walnut Creek Water Billing & Fees
Official Walnut Creek Water Links
Walnut Creek Water Department FAQ
Visit the official Casa Medanos Water System payment portal online. You can pay with a credit card, debit card, or eCheck. A guest pay option is available if you do not have an online account.
You can reach Casa Medanos Water System at (415) 409-4500. The office is open during Mon–Fri 8:00 AM – 5:00 PM.
Casa Medanos Water System is located at P.o. Box 4697, Walnut Creek, CA 94596.
Yes. Most municipal portals offer a one-time guest payment option. You only need your account number from a recent paper bill.
Many utilities accept past-due payments online, but reconnection timing varies. If your service is disconnected or scheduled for shutoff, call (415) 409-4500 before relying on portal timing.
Call Casa Medanos Water System immediately at (415) 409-4500. For after-hours emergencies, most departments have a 24/7 hotline. Do not attempt to fix a main line break yourself.
Contact Casa Medanos Water System at (415) 409-4500 at least 3 business days before your move date. Bring a valid ID and proof of address to start new service.