Sanitation Step-By-Step

Preparation of Piping

  1. Marked seven pipes for perforation.
    • Marked at 5 and 7 o’clock every 15cm beginning at 30cm.
  2. Drilled holes on the center of the markings.
  3. Attached caps onto the end of each perforated pipe where the last drain hole is 15cm from the end.
    • Cleaned the inside of the cap and the outside of the pipe.
    • Placed PVC cement on both the inside of the cap and outside of the pipe.
    • Attached the pipe and cap.
    • Twisted the cap a quarter of a turn to remove air bubbles.
  4. Attached appropriate fitting (elbows, T-pieces) to the opposite end of each perforated pipe
    • Dry-fit pieces together so that perforated holes are facing down
    • Drew markings across attachment gaps to ensure alignment when gluing
    • Glued pieces together using PVC cement
    • Twisted the fitting a quarter of a turn, matching the lines drawn for alignment purposes.
  5. Built a u-bend to be used as an access point for testing purposes.

    U Bend

    U Bend

  6. Measured placement of greywater trenches and marked using stakes and strings.
    • Determined an estimated location of the outlet pipes near the fence, and marked it with a stake.
    • Measured a distance of 7m away from the outlet pipe to the area designated for the leach field.
    • Marked out trench for the distribution trench (4.5m x 0.5m for the greywater leachfield and 2.9m x 0.5m for the blackwater leachfield) with the longest side parallel to the fence.
  7. Dug the trench until it is 0.5m deep.
  8. Measured placement for the finger trenches and marked with string.
  9. Dug trenches until it they are 0.7m deep.

    Trenches

    Trenches

  10. Leveled the bottoms of the trenches.
    • Placed a 3m level across the top the trenches, making it level using bricks and sand.
    • Placed a brick beneath the level in each trench.
    • Measured the distance between the top of the level and the top of the brick.
    • Adjusted the height of the bricks until the trenches are an equal distance below the level.
    • Level the trench by using the bricks from 5(a) as a reference point.

Leach Field

  1. Place the 3m level on the bricks
  2. On the opposite end, place bricks until the level is level
  3. Move the level to the set of bricks just placed and repeat the process
  4. Use this process for the remaining trenches
    • Adjust the height of the trenches as necessary, adding or taking away sand until they are level
    • Add gravel so that it is level at least 0.3m from the top of the trench.
    • Install 110 mm piping
      • Lay each pipe in its respective trench, with perforated holes facing down
      • Cut pipe to connect the perforated pipes
  5. Measure the distance between each fitting
  6. Mark that distance on a pipe
  7. Cut the pipe using a handsaw
    • Dry fit connecting pipes to ensure proper length, make adjustments as necessary
    • Glue connecting pipes in place.
    • Level piping.
  8. Use a 3m level to level the distribution pipe.
  9. Add or remove sand from under the pipe until it is level across the distribution trench.
  10. Using the distribution trench as a fixed point, level each pipe in the finger trenches in the same manner
    • Fill around the pipes in the finger trenches with gravel so that only the top of the pipe is showing.
    • Lay irrigation cloth over each pipe in the finger trenches.

      Cover with Irrigation Cloth

      Cover with Irrigation Cloth

  11. Cover the pipes with sand.
  12. Compact the newly placed sand.
    • Wet the sand using a hose
    • Using a tamper, tamp the new sand in each trench
    • If necessary, add more sand after tamping until the area is level with the ground

Installing Septic Tanks

  1. Staked off area for both the greywater and blackwater tanks in the designated location
    • a. 2.2 (l) x 1.4 (w) x 1.4 (h) (meters) for the greywater tank
    • b. 3.6 (l) x 2.2 (w) x 1.7(h)  (meters) for the blackwater tanks
  2. Dug the holes for the greywater and blackwater tanks.
  3. P1020857 (300x225)

  4. Leveled the bottom of each hole
  5. Made concrete for pad beneath the tanks.

    • Used a cement to sand ratio of 1:3 (one bag of cement for every three wheelbarrows of sand).
    • Added water until desired consistency was reached.
  6. Placed a layer of concrete 0.08m thick covering the bottom of each hole.
    • Leveled using a straight piece of wood with a level placed on top of it.
  7. Allowed the concrete to dry for half a day.
  8. Placed the tanks into the appropriate hole (making sure the blackwater tank with the baffle is on the appropriate side of the hole).

    Lowering Tank into Place

    Lowering Tank into Place

  9. Adjusted the tanks as necessary.
    • Adjusted height of the blackwater tank without the baffle so its outlet is higher than the inlet of the baffled tank
    • Installed an access point for the first compartment of the baffled blackwater tank.
  10. Ensured tanks are spaced and leveled properly.
  11. Simultaneously fill the tanks with water while filling the hole with concrete (this is done so the tanks will not collapse from the pressure of the concrete)
    • Made the concrete.
    • Placed concrete into hole until 1/3 of the way filled.
    • Placed sand into the hole until the sand reaches a level that is 20cm below the manhole cover.
    • Placed another layer of concrete until it is only 2cm below the manhole cover.
    • Leveled concrete in same manner as 5(a).
  12. Placed concrete in the manhole covers.
    • Use concrete that is made with stone and is a 1:5 cement bag to wheelbarrow of sand ratio.
  13. Place trash bags over the cement, weighing them down with bricks, to slow the drying time to allow for stronger concrete

Installation of Outlet Pipe

  1. Mark out piping for the connection between the tanks and their respective leach field.
    • Mark the outlet location of the tanks with a stake.
    • Determine appropriate path connecting the outlet to the leachfield (i.e. which pillars to put the pipes next to, the shortest distance between the outlet and the leachfield, etc.)
    • Mark the designated path using stakes
    • Tie string between the stakes and level with a string level.
    • Measure horizontal and vertical distances to determine the available pitch.
  2. Dig connecting trench for the pipe that leads directly into the entrance of the leach field.
  3. Create a smooth, even slope (which is 1m down for every 40m across) throughout the trench.
  4. Dig trench a little deeper to accommodate for the u-bend.
  5. Dry-fit piping for the rest of the trench
    • Mark all angles on joints to ensure appropriate fitting.
    • Check the pipes to ensure appropriate angle is reached
    • Adjust pipe levels accordingly by adding or taking away sand.
  6. Glue piping together using the same method as described in “Preparation of Piping” steps 3(a)-3(d)
  7. Cover piping with sand, placing sand beneath the pipes first to ensure pipes do not bow, and then carefully place sand above the pipes

    Blackwater Outlet

    Blackwater Outlet

Installation of Inlet Pipe

  1. Mark out piping for the connection between the tanks and the location of the ablutions container.
    • Mark the inlet location of the tanks with a stake.
    • Determine appropriate path connecting the inlet to the ablutions container (i.e. which pillars to put the pipes next to, the shortest distance between the inlet and the container, etc.)
    • Mark the designated path using stakes
    • Tie string between the stakes and level with a string level.
    • Measure horizontal and vertical distances to determine the available pitch.
  2. Dig the connecting trench for the pipe
  3. Create a smooth, even slope (which is 1m down for every 40m across) throughout the trench.
  4. Dry-fit the piping in the trench
    • Mark all angles on joints to ensure appropriate fitting.
    • Check the pipes to ensure appropriate angle is reached
    • Adjust pipe levels accordingly by adding or taking away sand.
  5. Label the inlet pipe
    • Place a 90° bend on the end of the pipe located under the ablutions container
    • Adjust the 90° bend so the shorter pipe attached to it is vertical, sticking out of the sand
    • Place a cap at the end of the pipe
    • Label the cap “graywater” or “blackwater” in accordance with the tank it connects to
  6. Glue piping together using the same method as described in “Preparation of Piping” steps 3(a)-3(d)
  7. Cover piping with sand, placing sand beneath the pipes first to ensure pipes do not bow, and then carefully place sand above the pipes.

    Inlet Piping

    Inlet Piping

Installation of Venting

  1. Dig a shallow trench for the vent pipe along the fence
  2. Install vent piping
    • Run a pipe from the vent, the length of the tank toward the fence, and then to the corner fence post.
    • Run a vertical pipe along the fence post
    • Attach a u-bend to the top of the pipe to prevent rain from falling inside the vent

      Vent Pipe

      Vent Pipe

  3. Cover the horizontal vent pipes with sand