The short version
- New lots hide rock, fill and poor soil
- Old lots hide forgotten lines, buried debris and old foundations
- Infill lots can have both
- Early investigation reduces cost surprises
Raw land
A cleared lot on a new development can hide rock, unsuitable fill from earlier grading, springs and poor soil. Utilities may be farther or deeper than the plan suggested. Drainage patterns can be altered by neighboring construction.
A site walk, test holes and a review of the plat help.
Older lots
On older lots, expect old lines, abandoned septic tanks, wells, buried debris and the footings of demolished buildings. Records are incomplete. Utilities may run in unexpected places, and trees add root zones.
Locating, potholing and demolition planning matter more here.
Infill and teardown lots
Infill lots combine old and new: an old sewer lateral that must be reused or replaced, old water service to retire, plus new utilities to add. Neighbors are close, so shoring and access need extra care.
Look for old tanks and lines before the foundation dig.
Reducing surprises
Investigate before pricing: review plats, call 811, walk the site and probe. Keep a contingency and agree on how unforeseen conditions are handled. Document what you find.
The cheapest problem is the one you find before the bucket does.
General information, not engineering, legal or safety advice. Rules and requirements vary by utility, city and county.
