What this due-diligence check covers
Topography affects driveway grade, foundation, retaining walls, septic layout, erosion and the direction water enters or leaves the parcel.
Development can trigger stormwater, grading or erosion-control requirements.
Why it matters before closing
Earthwork and drainage are common sources of budget overruns, neighbor disputes and permit delays.
What to verify
- Obtain reliable contours or topographic survey where needed.
- Identify swales, culverts, channels and uphill drainage.
- Check driveway and emergency-access grades.
- Ask about grading and stormwater permits.
Red flags that deserve follow-up
- Fresh fill or hidden drainage pipe.
- Erosion gullies through the building area.
- Neighbor’s runoff concentrated at the parcel.
- Only flat area is a drainage path.
Evidence to keep in the parcel file
- Topographic survey or lidar screen
- Drainage concept
- Local permit requirements
- Earthwork and retaining estimate
Questions to ask before the deadline
- Where does water enter and leave?
- What is the driveway grade?
- Will grading require a permit?
- Are retaining walls likely?
- Who maintains existing culverts?