Septic Design - Flows
Question: Is there any wonder why folks seem to be having so many problems with OSSFs (septic systems) in Texas?
Answer: Beginning with the new rules that came out in 1997, design flows are on the order of 1/2 what they used to be - even though homeowners aren't universally generating 1/2 as much sewage every day.
The design numbers in these new rules are now mostly average flows, and as such do not provide any reserve for the occasional higher, or peak flows. These higher, or peak flows, often exceed the design values, causing the the system to not be able to perform at the levels expected of these systems.
For systems to operate correctly, using only these average flows, requires the use of flow equalization. With flow equalization preceding the OSSF, the peak flows will be moderated, so the balance of the system can be designed for these much lower flows.
Without the use of flow equalization, however, the OSSF must be designed for the higher flows which accommodate peak flows that naturally occur on a daily, weekly, and monthly basis. Otherwise, the OSSF will dramatically under perform.
Number of Bedrooms |
Harris County - Example Minimum Gallons Per Day |
30TAC285, Table III Minimum Gallons Per Day |
2 |
300 |
180 |
3 |
450 |
240 |
4 |
600 |
300 |
5 |
750 |
360 |
6 |
900 |
420 |
7 |
1050 |
480 |
8 |
1200 |
540 |
9 |
1350 |
600 |
10 |
1500 |
660 |
Previous Article : Leach Field - - Next Article : Septic Treatment
-
Providing Quality Service...Guaranteed In the Greater Austin Area of Travis, Hays, Williamson, Burnet, & Bastrop Counties
, Wells Branch, Briarcliff, Westlake Hills, WoodCreek, Kyle, Dripping Springs, Serenada, Leander, Williamson County, Misc Locations, Bell County.
Call (512) 338-1804 for fast, dependable service.
-
Maintenance Here's a logical fact of life regarding septic systems: All septic systems require maintenance to keep them working correctly and to ensure their long life....
-
Pumping Frequencies The table below provides an estimate of pumping frequency in years, based on the size of the first tank in gallons, and the number of...
-
Aerobic System Pumping Aerobic Treatment Units (ATU) generally require more frequent pumping than do septic tanks of comparable size. There are 2 reasons: The...
-
Septic Leach Fields If there are strong odors in the soil treatment area (around an in-ground drain field, bed or mound),...
-
Septic Problems Why Doesn't My [New] Septic Work?In Texas, the rules currently governing septic systems are minimum standards. In other...
-
Septic Drain Fields Care for your drainfieldYour drainfield is an important part of your septic system. Here are a few things...
-
Seller Says "Too Bad" Seller Says “Too Bad” After Homebuyers Find Rotting Septic Tank Under Plywood (From Pumper Magazine, October 23, 2018)...
-
Septic Tank Size Septic Tanks are usually about 4.5 feet wide x 8.0 feet long x 6 feet tall. Tanks are...