Look-Ahead Slips After a Rain Event
You are running the sitework package on a warehouse project. The three-week look-ahead shows mass grading finishing this week, then utility trenching, then a subbase lift. A two-day rain event has saturated the subgrade, and the geotechnical tech says the material needs to dry before proof-rolling. Your grading sub is idle and asking whether to demobilize. The utility sub is scheduled to start in four days and has already staged pipe on site. The owner wants the building pad certified by month-end, and your last schedule update showed zero float on the pad milestone.
1. How do you update the look-ahead, and what makes the update defensible?
Read the worked answer
Re-sequence rather than simply pushing everything back.
- Confirm the geotech's drying window with the tech and get a realistic earliest proof-roll date, not a guess.
- Look for work that can proceed without the pad: utility trenching in areas that drain and are not blocked by the wet subgrade, staging, and layout.
- Move the grading sub to those areas or to another portion of the site to avoid demobilization if there is productive work; if there is not, negotiate a short standby rather than a full demob and remob.
- Rebuild the three-week look-ahead with the drying constraint shown explicitly as a predecessor, and show the utility start as conditional on the proof-roll.
The update is defensible because it is built on a verified constraint (geotech's drying assessment), it names the logic ties, and it protects the pad milestone by keeping other work moving. A look-ahead that just slides every bar two days ignores the real dependency and hides the float loss from everyone downstream.
2. The owner insists the pad be certified by month-end. What do you tell them, and how do you frame it?
Read the worked answer
Tell them the truth with options, not a promise you cannot keep.
Frame it as: the constraint is subgrade moisture, verified by the geotech, and proof-rolling wet material would fail and require rework. Then present the choices:
- Option A: hold for drying (give the earliest realistic date) and keep the pad milestone intact with no rework risk.
- Option B: accelerate drying with discing/aeration and additional equipment, at added cost, to pull the date in by a stated number of days.
- Option C: shift the critical path by starting building erection on the unaffected portion while the pad cures, if the sequence allows.
Give each option a cost, a date, and a risk. The reasoning is that the owner is buying certainty, and certainty comes from a clear constraint plus priced alternatives. Agreeing to a date the subgrade cannot support sets up a failed proof-roll, a rework claim, and a missed date anyway. Document the conversation and the owner's decision in writing.