We're clearing and grading a 1.5 acre lot for a new landscape and pond.

Yes. At 1.5 acres, you are almost certainly over the 1-acre threshold triggering the NPDES Construction General Permit (CGP) (40 CFR 122.26). This is federal law administered by your state (or EPA Region).

Immediate Requirements:

1. Notice of Intent (NOI): File before breaking ground.
2. SWPPP (Stormwater Pollution Prevention Plan): Must be written before construction starts. It requires: Site map with drainage patterns, slopes, and discharge points. Erosion & Sediment Controls (BMPs): Silt fence, inlet protection, stabilized construction entrance, stockpile management. Perimeter controls are required before clearing starts. Stabilization Deadlines: Disturbed areas inactive for 14 days must be stabilized (seed/mulch/blanket) — often 7 days near sensitive waters (CGP Part 2.2.14). Inspections: Every 7 calendar days AND within 24 hrs of a 0.5" rain event. Must be documented by a "qualified person."
3. Dewatering: If you pump the pond excavation, you need a sediment bag/tank and possibly a separate dewatering permit. Discharging turbid water is a violation.

State/Local Layers:

• Many states (CA, WA, FL, NC, etc.) have stricter thresholds (e.g., 5,000 sq ft) or specific pond/liner rules.
• Grading Permit: Often separate from clearing; requires engineered drainage plan.
• Wetlands/Streams: If the pond connects to or impacts jurisdictional waters (WOTUS), you need Section 404/401 permits (Corps of Engineers/State). Do not assume "dry land" is safe.

Practical Tip: Hire a CPESC (Certified Professional in Erosion and Sediment Control) to write the SWPPP. Fines run $50k+/day. The local permit is the floor, not the ceiling.

Yes — beyond the local land-clearing permit, you must address stormwater management under federal, state, and often local regulations, especially since you’re disturbing 1.5 acres (which triggers key thresholds).

Key Considerations:

1. NPDES Stormwater Permit (Clean Water Act) - If your disturbance is ≥1 acre, you likely need coverage under the EPA’s National Pollutant Discharge Elimination System (NPDES) Construction General Permit (CGP) — unless your state has delegated authority (most do). - Action: Submit a Notice of Intent (NOI) to your state’s environmental agency (e.g., DEQ, DNR) before breaking ground. Develop and implement a Stormwater Pollution Prevention Plan (SWPPP). - SWPPP must include: Erosion controls (silt fences, sediment basins), stabilization practices, inspection schedules, and spill prevention.

1. Local Ordinances - Many municipalities require detention/retention ponds, bioswales, or low-impact development (LID) features for post-construction runoff — especially since you’re adding a pond. - Check if your pond design counts as a stormwater BMP (Best Management Practice). If so, it may need engineered outlets, overflow controls, and maintenance plans.

1. Post-Construction Requirements - Even after grading, you may need to ensure the site doesn’t increase peak runoff or pollutant loads. Your pond should be designed to attenuate flow and treat sediments/nutrients (e.g., with forebays, vegetative buffers).

1. Wetlands/Stream Buffers - Avoid disturbing wetlands or streams without a Section 404 permit (USACE). Verify no jurisdictional waters exist via a wetland delineation if unsure.

Bottom Line:

✅ File NOI + SWPPP for NPDES/CGP (state-level). ✅ Design pond as a stormwater BMP with outlet control. ✅ Stabilize slopes ASAP — seed/mulch within 14 days of disturbance. ✅ Inspect weekly and after 0.5” rain.

If unsure about state-specific rules or pond design, consult a licensed civil engineer or erosion control specialist. Noncompliance risks fines ($$$/day) and shutdowns.

References: EPA CGP (2022), 40 CFR §122.26, local stormwater manuals.