If you use a lot of water SOLELY for outside purposes - i.e. lawn, garden, pool (water that does not return to our sewerage system for necessary treatment), a sub-meter which measures outside water use only may be cost effective. The Sewer Usage on your bill would only reflect the "household" or inside portion of the consumption.
You will first need to contact a Registered Master Plumber to determine the on-site plumbing modifications required to provide a separation of household and outside services. Please note: a WSSC Registered Master Plumber must install the Sub-Meter.
One-time WSSC Sub-Meter Installation charge:
Total WSSC Costs: $1189.00
* WSSC cannot estimate this expense. The cost of on-site plumbing is negotiated between the customer/property owner and the Registered Master Plumber who will make the modifications. For further details, contact Permit Services at (301)-206-4003 or toll-free at 1-800-643-8400.
WSSC's water consumption and sewer usage charges are based on metered public water use. This is a widely accepted practice when a utility provides both public water and sewer services. Maryland Law requires that WSSC shows a separate charge for Water Consumption and for Sewer Usage. The owner, tenant, or occupant who uses water "exclusively" for any purpose which does not enter the sewerage system of the WSSC, "shall not be charged a sewer usage charge for the water so used, provided, however, that they pay to the WSSC the cost of installing such a separate metered connection."
Main Meter registers 45,000 gallons of water (500 gallons per day) in a 90-day billing period. Sub-Meter, measuring outdoor usage, registers 27,000 gallons of water used outside in a 90-day billing period.
Registered Difference between the Main Meter and the Sub-Meter consumption is 18,000 gallons of water (200 gallons per day), which represents the amount used in house and subject to Sewer Usage Charge.
The Bill calculations based on this example are:
WATER CONSUMPTION RATE
For water use at average daily consumption (ADC) of 500 gallons: $4.61 X 45,000 = $207.45
SEWER USAGE RATE (with a Sub-Meter)
For sewer use at average daily consumption (ADC) of 200 gallons: $5.08 X 18,000 = $91.44
SEWER USAGE RATE (without a Sub-Meter)
For sewer use at average daily consumption (ADC) of 500 gallons: $6.62 X 45,000 = $297.00