Understanding Your Water Bill

This bill explainer walks you through important information and shows you how usage is calculated, explains the rate structure, and details the calculations used to determine water and sewer charges. You’ll also learn about the fees on the bill, what the monies are used for and how they are calculated.

Enhancements to Customer Engagement on High Bills

Download Bill Explainer Descargue la explicación de facturas en español

The "How Much Water Do I Use?" section of your WSSC Water bill shows the average gallons you use per day, based on your bill period and latest meter reading. For this bill, the customer's meter reading indicated they used 13,000 gallons in a 90-day period. Dividing the 13,000 gallons by the 90 days gives the amount of 144 gallons used per day. According to this bill, a typical customer uses 48 gallons per day.

A How was 13,000 gallons calculated? We subtract your previous meter reading from your current reading and that determines your usage.

B Average gallons used per day is calculated by dividing the total gallons used during the bill period (13,000) by the number of days in the bill period (90), which can be found in the upper right corner. For this bill, the average gallons used per day is 144.

How Does The Rate Structure Work?

We use a four-tier rate structure to determine how you are charged for water/sewer. This customer used an average of 144 gallons of water per day. That means their usage is billed at the rates in the first two tiers.

Tier	Gallons Per Day	Water	Sewer
1	0 - 80.9999	$7.33	$9.72
2	81 - 165.9999 144 gallons falls ↑ in this range	$8.28	$10.79
3	166 - 275.9999	$9.53	$13.55
4	276 & Greater	$11.17	$17.90

How Am I Charged For Water/Sewer?

On this bill, there are two lines for water charges. To determine the number of gallons on each line, multiply the largest number of gallons in Tier 1 (80.9999) by the number of days in the bill period (90).

80.9999 x 90 = 7,290 gallons

To determine how many gallons will be charged in Tier 2, subtract 7,290 gallons from the total gallons used (13,000).

13,000 - 7,290 = 5,710 gallons

WATER CHARGES - July 2025 Rates $100.72

7,290 gallons x $6.69 per 1,000 gallons $53.44

5,710 gallons x $7.56 per 1,000 gallons $47.28

Sewer charges are based on water usage unless you have a submeter. Using the sewer rate, follow the same calculation to determine your sewer charges.

Calculating Charges For This Bill

Tier	Gallons Per Day	Gallons in Bill Period	Rate (Water)	Cost Calculation	Water Charges
1	0 up to 80.9999	80.9999 × 90 days = 7,290 gallons*	$7.33	7.29 × $7.33 =**	$53.44
2	81 up to 165.9999	(144.44 - 80.9999) × 90 days = 5,710 gallons	$8.28	5.71 × $8.28 =	$47.28
3	166 up to 275.9999	Not Used	$9.53	-	-
4	276 & Greater	Not Used	$11.17	-	-
					$100.72

To calculate a monthly bill, replace 90 days with 30.

Rate Per 1,000 Gallons

WSSC Water bills in thousand-gallon increments on a quarterly or monthly basis. Billing per thousand gallons is common practice for water utilities.

*7,290 gallons ÷ 1,000 = **7.29

State of Maryland Bay Restoration Fee (BRF)

WSSC Water collects this fee, levied by the state, and turns it over to the Maryland Department of the Environment (MDE). MDE uses the revenue to fund improvements to water resource recovery facilities owned by utilities, including WSSC Water. The BRF is assessed each bill period for residential and commercial customers. CAP customers qualify for an exemption.

A typical residential customer is assessed approximately $15 for a 90-day bill period or $0.1643 per day. If your bill period is 90 days, the BRF would be $14.78 ($0.1643 x 90 = $14.78). If you’re billed monthly, the BRF would be $4.92 for a 30-day bill period.

Account Maintenance Fee (AMF)

Recovers the cost of service associated with maintaining and servicing customer accounts, including purchasing, maintaining, reading, and replacing meters; processing meter readings; generating and mailing customer bills; and providing customer services. The fee is based on meter size and assessed each bill period.

For a typical residential meter (5/8” – 1”), the AMF is $32.94 or $0.36098 per day. If your bill period is 90 days, the AMF would be $32.49 ($0.36098 x 90 = $32.49). If you’re billed monthly, the AMF would be $10.83 for a 30-day bill period.

Infrastructure Investment Fee (IIF)

Funds a portion of the debt service associated with water and sewer pipe reconstruction under WSSC Water’s Capital Improvements Program. The fee is based on meter size and assessed each bill period. Most residential meters range from 5/8” to 1” in size.

For example, the IIF for a 5/8” meter is $22.67 or $0.2484 per day. If your bill period is 90 days, the IIF would be $22.36 ($0.2484 x 90 = $22.36). If you’re billed monthly, the IIF would be $7.45 for a 30-day bill period.

Customer Assistance Program (CAP)

WSSC Water customers enrolled in CAP receive a credit up to $247 per year to cover the cost of the Account Maintenance Fee and Infrastructure Investment Fee. Click here to learn more.

Learn More About Fees and Other Charges

Last Modified: January 21, 2026, 2:36 pm EST