“Building Code Of The Day”

Question:  Gray water systems shall be designed to distribute the total amount of estimated gray water on a ________ basis.

A) hourly

B) twice daily

C) daily

D) weekly
E) All of the above

Answer:   C Sec 1502.8

1502.8 Procedure for Estimating Gray Water Discharge.
Gray water systems shall be designed to distribute the total amount of estimated grey water on a daily basis. The water discharge for gray water systems shall be determined in accordance with section 1502.8.1 or 1502.8.2

1502.8.1 Single Family Dwellings and Multi- Family Dwellings.

The gray water discharge for single family and multi-family dwellings shall be

calculated by water use records, calculations of local daily per person interior water use. or the following procedure:

(1) The number of occupants of each dwelling unit shall be calculated as follows:

First Bedroom                         2 occupants

Each additional bedroom      1 occupant

(2) The estimated gray water flows of each occupant

shall be calculated as follows:

Showers, bathtubs. 25 gallons (95 L.) and lavatories per day/occupant

Laundry               15 gallons (57 L.) per day/occupant

(3) The total number of occupants shall be multiplied by the applicable estimated gray water discharge as provided above and the type of fixtures connected to the gray water system.

1502.8.2 Commercial, Industrial, and Institutional Occupancies. 

The gray water discharge tor commercial, industrial, and institutional occupancies

shall he calculated by utilizing the procedure in Section 1502.8.1. water use records, or other documentation to estimate gray water discharge.




From the UPC Chapter 2 Definitions-

Gray Water.
Untreated wastewater that has not come into contact with toilet waste, kitchen sink waste, dishwasher waste or similarly contaminated sources. Gray water includes

wastewater from bathtubs, showers, lavatories, clothes washers, and laundry tubs.  Also known as grey water, graywater and greywater.