UCHD, Protecting Your Health.


Tuesday, 08 December 2015 02:21

Septic System Information

If you're thinking of inspecting your own sewage treatment system (STS) starting in 2020 it's a good idea to do your homework on how your STS should be functioning. 
COMING SOON we will have information on each of the following sewage treatment systems and some common issues users of each of these systems experience.

In the meantime, take a look at the OSU extension office's septic system maintenance page here.

Treatment and Pretreatment Types

Septic Tanks

Septic tanks help keep solid waste from clogging the rest of the system. When maintained correctly, solid waste will sink to the bottom of the tank allowing the rest of the sewage to move on the the next part of treatment. Septic tanks have evolved over the years to have more ways to keep solids from causing damage to the septic system.  In the pictures below you will see a cross section of a septic tank. You'll see the sludge layer (solids) at the bottom and a scum layer (Oils and other fluids lighter then water) at the top. It is important to regularly pump out your septic tank in order to make sure that sludge and scum layers don't build up and cause irreversible damage to the system.

How often you should pump your tank is different for each system. It depends on how many people live in your home and the size of your septic tank.Below is table created by The Ohio State University that determines how often you should get your tank pumped based on those two factors.


Table 1. Estimated septic tank pumping frequency (in years) for different size tanks for 1 to 9 people in a household of year-round residence.
Note: If a garbage disposal is used, more frequent pumping is required. 
Tank Size
(in gallons)
Number of People
1 2 3 4 5 6 7 8 9
500 5.8 2.6 1.5 1 0.7 0.4 0.3 0.2 0.1
750 9.1 4.2 2.6 1.8 1.3 1 0.7 0.6 0.4
1,000 12.4 5.9 3.7 2.6 2.0 1.5 1.2 1 0.8
1,500 18.9 9.1 5.9 4.2 3.3 2.6 2.1 1.8 1.5
2,000 25.4 12.4 8 5.9 4.5 3.7 3.1 2.6 2.2
2,500 31.9 15.6 10.2 7.5 5.9 4.8 4.4 4 3.0

Leach Field

One of the most common treatment types is a leach field. Leach fields start with a diversion box which diverts sewage into several long leach lines that allow sewage to trickle through the ground water without discharging to the surface. It relies on the microbes naturally present in the soil to clean the sewage before it is reused. Leach fields usually rely completely on gravity to move sewage along to long leach lines that allow the sewage to "leach" into the soil. Sometimes due to higher elevations a electrical pump is needed to get sewage to the leach field.

Common issues with leach fields occur when septic tanks are not pumped regularly and solids are allowed into the leach field. The solids clog the lines and don't allow sewage to leach out and be cleaned naturally. Depending on where the clog is, sewage can surface up into your yard or back into your home causing human and environmental health hazards. In order to make sure clogs don't occur in your leach field, you should pump the septic tank out regularly according to the chart above and switch the elbow in the diversion box at least every 6 months. Additionally, avoid parking cars, building anything or in anyway compacting the leach field. 

Subsurface Sand Filter




 Please see our Aerator Systems page.

EPA Grant Information

Union County Health Department was awarded a grant to fix and replace failing septic systems in Union County. If you know you have a problem with your system but do not have the funds to fix it, contact Holly Rast for information on how to apply!

Holly J. Rast
(937) 645-2043

Published in Water & Sewage
Thursday, 25 August 2011 01:55

Septic Systems

New 2015 Sewage Rules!

icon OAC-3701-29-UCHD Sewage Rules Supplement

These new statewide sewage rules have made it necessary for the Union County Health Department (UCHD) to expand its current Operation and Maintenance (O&M) program to include every septic system in Union County. To understand your responsibilities under the new 2015 sewage rules check out the O&M program page

Operation and Maintenance Program 

Learn what you can expect during the O&M phase in period, fee information and more! Click here for more information.

Septic Systems 

What happens when you flush the toilet? Many people don’t know! Every time you flush the toilet or use water in any way in your home, you are generating wastewater. When wastewater leaves your home it needs to be treated before it re-enters the environment. Depending on the type of septic system or Sewage Treatment System (STS) you have your wastewater is treated naturally by the ground, with the help of special filter bed or by an aerator. To find out more about your system type and how it treats your wastewater follow this link to our septic system information page.

What you need to know

Sewage is the waste water released by residences, businesses and industries in a community. It is 99.94 percent water, only 0.06 percent of the water is dissolved and suspended solid material. The cloudiness of sewage is caused by suspended particles. Pathogens or disease-causing organisms are present in sewage. Coliform bacteria are used as an indicator of disease-causing organisms. Sewage also contains metals, minerals and nutrients (such as ammonia and phosphorus).

Private sewage systems are used by households not served by a centralized sewage system. This is accomplished by site evaluations, permits and inspections of new and altered systems, and the investigation of complaints/malfunctioning systems. Union County regulates private sewage systems in accordance with the local sewage treatment system rules, Ohio Revised Code (ORC) 3718, and the Ohio Administrative Code (OAC) chapter 3701-29.

Public sewage systems are those systems where households are connected to a centralized sewerage system. Public systems are not regulated by the Health Department, but are governed by the Ohio Environmental Protection Agency (OEPA). However, in Union County, any commercial (or semi-public) sewage system smaller than 25,000 gallons per day is inspected by the Health Department, through a contract with the OEPA

OAC 3701-29 (Chapter 29)

icon Septic System Inspection Form

icon Environmental Health Fee Schedule - see Section IV, C & D on page 2 for fees associated with household sewage systems

Installing a private sewage system?

Installing a private sewage system requires a permit from the Union County Health Department. There are several steps that must be completed before a permit can be obtained. Some of these steps include a site evaluation. A soil scientist must test the soil in which the system will be installed.

Once a permit is issued, installation must be done by a registered installer.  Click here for a list of registered installers.
A soil scientist must test the soil in which the system will be installed.  Click here for a list of local soil scientists.
Some repairs on existing systems must also be done by registered sewage installers.  

icon Registered-Sewage-Installers

EPA Grant Information

Union County Health Department was awarded a grant to fix and replace failing septic systems in Union County. If you know there is a problem with your system but do not have the funds to fix or replace it, contact Holly Rast for information on how to apply!

Holly Rast
(937) 645-2043


Published in Water & Sewage