I'm really just looking for any general comments here. More specifically related to the flow of water through various materials i.e. clayey/sandy or sandy/gravel or a granular material similar to a CA7 (3/4" crushed stone). Feel free to reference actual soil designations unfortunately I'm no geotech so I really can't get too specific. Which is also why we may get some borings.
Scope: Determine what is causing increased sump usage at residence home.
Background: (See sketch).
The retaining wall was replaced approx, 1.5 years ago. The existing wall failed due to lack of geogrid. Geogrid was placed in the new wall. It is not know if site soils (sandy / clayey material) which it was designed for were used as reinforced back fill or if granular materials were used. Ever since the replacement the sump usage has increased. It used to run every 30mins - 1hr, now it is down to every 3min. There is a point at which the water 'rushes' up to then it fills fairly slowly. However if you raise the pump, this 'slow' down point also raises.
Back-feeding in the system has been checked for.
A possibility maybe some old abandoned drainage pipes that used to run across the lot. Possibly these were disturbed during construction. For now this is unlikely and lets assume it is not the problem.
For now I am wondering what sort of flow could be expected into the sump from the ground water level / pond level. I'm thinking that the water level tapers off as it approaches the home and now it is getting closer and thus higher???
EIT
Scope: Determine what is causing increased sump usage at residence home.
Background: (See sketch).
The retaining wall was replaced approx, 1.5 years ago. The existing wall failed due to lack of geogrid. Geogrid was placed in the new wall. It is not know if site soils (sandy / clayey material) which it was designed for were used as reinforced back fill or if granular materials were used. Ever since the replacement the sump usage has increased. It used to run every 30mins - 1hr, now it is down to every 3min. There is a point at which the water 'rushes' up to then it fills fairly slowly. However if you raise the pump, this 'slow' down point also raises.
Back-feeding in the system has been checked for.
A possibility maybe some old abandoned drainage pipes that used to run across the lot. Possibly these were disturbed during construction. For now this is unlikely and lets assume it is not the problem.
For now I am wondering what sort of flow could be expected into the sump from the ground water level / pond level. I'm thinking that the water level tapers off as it approaches the home and now it is getting closer and thus higher???
EIT
