Leachate Collection Sump Design

From The Pumps Point of View - by John Hasslen

Effective Collection of Leachate
Long Life
Leave Trash in the Landfill
Minimum Head on Liner

  • Designing deep sumps allows pumps to run longer without increasing head on liner. The goal is to keep infiltration gallery as wet as possible.
  • Design sump inlet area for velocity of 0.1 foot per second. Slots are more effective in retaining small particles then round holes.
  • Design larger infiltration area around sump. Decrease velocity to one (1) foot per minute in the infiltration gallery.
  • Design guidelines should be taken from good water well design practices.
  • It has been proven in water well design that extended pump run cycles and low velocity reduce or delay incrustation and infiltration of fine solids.
  • Design using coarse filter pack around sump and then finer gravel around this to reduce infiltration.
  • Small sumps and infiltration gallery create greater changes in pressure (velocity) which increase precipitation.
  • The more often gallery is exposed, the more progressive the reduction of open area.



  • Maximize possible inlet area to reduce velocity of flow through infiltration gallery and sump openings.
  • Reduce pumping rates to extend pumping period.
  • Use more then one sump to increase infiltration area and reduce velocity.
  • Periodic maintenance and cleaning.
  • Strictly enforce good construction practices. Use clean infiltration material of controlled size.


“Water Well Handbook”, Keith E. Anderson Published by Missouri Water Well and Pump Contractors Association, Inc.
“Ground Water & Wells”
Published by Johnson Division, UOP Inc.
“Ground Water & Wells” 2nd Edition, Fletcher G. Driscoll
Published by Johnson Division