GUIDELINES FOR INSTALLING SEPTIC SYSTEMS IN HENRY COUNTY

1. Regardless of acreage size, all septic work MUST have a permit.  Submit a septic plan to our office. An application completed accurately and legible and fee paid.  After plan is approved, a permit will be issued and must be posted at the construction site before any installation begins on the septic system.  New construction under 10 acres requires a certified engineers plan and a certified soil scientist’ profile.  Over 10 acres installer or owner can submit the plan.  The following should be shown on the plan with appropriate distances from the septic system. All septic work must have a permit and be inspected.

2. Wastewater Treatment systems shall be at least 100 feet away from any potable water source used for human or animal consumption, (except)

          a) Rural water lines and meters must be 10 feet from septic system.

          b) Tank should be no closer to house than 10 feet with one cleanout between the house and tank and one inspection port on one lateral.  

          c)  Lateral lines must be at least 10 feet from property lines.

          d)  Lagoons must be at least 100 feet from property lines and the residence it serves and 200 feet from all adjoining residences.

          e)  Septic tank size shall be a minimum of 1,000 gallon.  All tanks require a tank riser over inlet and outlet baffles. No metal tanks.

          f)  Lateral field shall be a minimum of 300 linear foot for 2 bedroom, 400 foot for 3 bedroom, 500 foot for 4 bedroom, etc.

          g)  Lagoons shall have a tank installed ahead of the lagoon. Minimum size of the lagoon  shall be 30x40 feet or 1200 sq. feet and 3 to 5 feet deep, 3 to 1 slope inside and outside.  Minimum 4 foot tall fence must be installed. No discharge pipe allowed.                                             

3.  All installers must be registered with our office and state registered.

          a)  Homeowners who want to install their own systems must also register with our office. Registration includes paying a fee, attending a class and taking a test.

          b)  A current registration list is provided at the Health Department.

4.  A 24-hour notice is required for an inspection by the Sanitarian.  All septic system installations must be inspected in order to be approved.  No backfilling before inspection takes place. 

5.  Any deviations must be approved by the Henry County Board of Health Trustees during the regular monthly board meeting.

6.   Septic systems installed without a final inspection may result in the system being dug up at the owners or installers expense.  Fines may apply.

CONVENTIONAL  LATERAL  FIELD  INSTALLATION

01)  A clean out between the house and the septic tank.

02)  4 inch SCH 40 PVC pipe used in the inlet and outlet of the septic tank.

03)  A 1000 gallon concrete or state approved polyurethane tank is the minimum size.

04)  The tank must be level and adequate fall on the inlet and outlet lines 1/8" per foot

        is desired when systems are gravity fed.                

05)  There must be a 6" pump-out on the top of the tank, either flush or above 

       ground surface and a manhole riser if tank is 18 inches or more below ground.

06)  Baffles/tees correctly in place inside the tank.

07)  A 6 inch inspection port shall be provided over the inlet and outlet baffles of each

        tank and terminate at or above grade.        

08)  Distribution box (if used) on level sites must be laid level on rock, if trenches are on

       different grade then system must be stepped down with the end connection  at least 1'

       higher than the receiving line or use a drop box.

09)  Inlet and outlet pipes must be sealed water tight, all lines must be solid pipe from

       box to laterals.  (PVC glue is required on all joints)

10)  In moderate soil conditions the sufficient lateral footage is 300 linear foot.

       The average 2 bedroom house is 300 linear foot of conventional laterals in

       a 24" ditch.  This is equal to 300 linear foot of 10" SB2 or 300 linear foot

       of the infiltrator chamber or EZ Flow.  In poorly drained soils or small lots

       alternative systems may required and a registered installer may be

       required.

11) The trench bottom must be excavated level.  On fields with lateral on the

      same grade  the ends should be tied together. Laterals that are not tied

      together, all ends MUST be capped.

12) 12" of rock is required under the lateral distribution line.  The rock must

       be at least 1 1/2 " clean, washed screened rock.

13)  6" of rock is required over the distribution line 2" over the top of the line

       and 4" around.

14)  Distribution lines must be level not to exceed over 2" of fall in a 100 foot

       line as determined by a transit or laser.

15)  8" of straw or synthetic fabric is required to be placed as a breathing

       barrier on top of the 6" rock cover over the line. (Tar paper should not be

       used)

16)  Backfill with un-compacted topsoil and berm up ditches to allow for

       settling and detouring of surface water.

17)  One inspection port is required in the field.  The stand pipe may or may

       not be connected to the lateral line.  This is for a field locator and

       homeowner observation of the soil saturation capabilities.

Henry County Health Septic Standards

An application completed accurately and legible and fee paid.  Submit a septic plan to our office.  If plan is approved, a permit will be issued and must be posted at the construction site before any installation begins on the septic system. 

New construction under 10 acres requires a soil morphology and maybe a certified engineers plan.  Regardless of acreage size, all septic work must have a permit.

All installers must be registered with the state of Missouri (HB1433) and with Henry County Health Center. (Henry County Wastewater Ordinance 89-1).

Homeowners who want to install their own systems must also register with our office.  Registration for installers and homeowners includes paying a fee, attending a class and taking a test (annually).

A current registration list is provided at the Health Center or on line at henrycountyhealth.org.

A 24-hour notice is required for an inspection by the Environmental Specialist.  All septic system installation must be inspected in order to be approved.  No backfilling is allowed before inspection takes place. 

Septic systems installed without a final inspection may result in the system being dug up at the owners and/or installer’s expense.  Pictures are not a substitute for an inspection.

A soil’s profile must be conducted on all new construction sites under 3 acres by a certified Soil Scientist.

Wastewater Treatment systems shall be at least 100 feet away from any potable water source used for human consumption.

Rural water lines and meters must be at least 10 feet away from septic system.  Tanks should be no closer to the house than 10 feet with a clean out installed between the house and the septic tank. Cleanouts are required every 90 feet or 90* turn.

A 1000-gallon tank is the minimum size (SEE CHART)

Number of bedrooms                                       Minimum Liquid Capacity

1 -3                                                                  1000 gallons

4                                                                      1250 gallons

5                                                                      1500 gallons

The tank must be level and adequate fall on the inlet and outlet 1/8” per foot is desired when systems are gravity fed.  4-inch SCH 40 PVC pipe must be used in the inlet and outlet of the septic tank past the hole of excavation to solid ground.  All tanks require a riser over inlet and outlet baffles.  A middle manhole riser is required if tank is 18” below the ground surface (19CSR20-3.060).  Baffles/tees must be placed correctly inside the tank. 

Lateral lines must be at least 10 feet from property lines.  Lateral field shall be a minimum of 300 linear feet for a 1 or 2 bedroom house, 400 linear feet for a 3 bedroom house, 500 linear feet for a 4 bedroom and 600 linear feet for a 5 bedroom house.

Distribution box (if used) on level sites must be laid level on rock, if trenches are on different grade then system must be stepped down with the end connection at least 1 inch higher than the

receiving line or use a drop box.

Inlet and outlet pipes must be sealed watertight; all lines must be solid pipe from box to laterals. PVC glue is required on all joints.

In moderate soil conditions the sufficient lateral footage is 400 linear feet for the  average 3-bedroom house.  In poorly drained soils or small lots, alternative systems may be required. No reductions are given.

The trench bottom must be excavated level.  All lateral ends must be capped.  Distribution lines must be level, not to exceed over 2” of fall in a 100-foot line as determined by a transit or lazar.

Backfill with un-compacted topsoil and berm up ditches to allow for settling and detouring of surface water.

One inspection port is required in the field.  The standpipe may or may not be connected to the lateral line.  This is for a field locater and homeowner observation of the soil saturation capabilities.  Laterals must be installed on 10-foot centers.

Lagoons shall have a tank installed ahead of the lagoon.  Minimum size of the lagoon shall be 30x40 feet or 1200 sq. feet and 3 to 5 feet deep, 3 to 1 slope inside and outside.  Minimum 4-foot tall fence must be installed.  No discharge pipe allowed.  Routine maintenance is required, mowing, eradicating algae growth, clearing shrub growth, and keeping good sunlight penetration on water surface. Lagoons must be at least 100 feet from property lines and residence it serves and 200 feet from all adjoining residences. Solid SDR 35 or heavier pipe must be used from the Sch 40 pipe connection to lagoon.  A block or splash pad must be present to secure pipe into the lagoon.  The pad or block should be placed in the center of the lagoon.

All sites must have a tract of ground that contains a minimum of 10,000 square foot of suitable land for sewage disposal.

During the final inspection the Environmental  Specialist will complete the final inspection form and give a copy to the owner or installer.

For further references on onsite sewage regulations the following are listed for you, in conjunction with Henry County Wastewater Ordinance 89-1.

Section 303, 208 and 201 of the Federal Clean Water Act.

10 CSR 20-8.021 DNR sewage standards.

Chapter 701 RSMO.

Dept. of Health & Senior Services 19CSR 20-3.060.

House Bill 1433