Apex, NC Environmental Rules: Grading & Drainage (2026)

Apex's grading and drainage controls sit at the intersection of four documents: the Apex UDO (Article 6 Watershed Protection Overlay Districts; Article 8 Stormwater), the Apex Soil and Erosion Control Ordinance, the Town-adopted NC Stormwater Design Manual published by NC DEMLR, and the Apex Standard Specifications and Standard Details (Section 400). Post-construction Stormwater Control Measures (SCMs) are designed to capture the design storm — historically the 1-year 24-hour storm event under the now-suspended Jordan Lake new-development rule 15A NCAC 02B .0265 and the first inch of rainfall for the runoff treatment volume — and release it slowly over several days to mimic predevelopment hydrology. SCMs include detention basins, bioretention cells (rain gardens), wet ponds, sand filters, level spreader/vegetated filter strips, infiltration trenches, and stormwater wetlands. Each SCM must be sized using the NC Stormwater Design Manual and must achieve the nutrient reduction targets generated by the NC DEQ SNAP spreadsheet tool for projects in the Neuse River Basin (in effect for Apex since July 2024). For the Jordan Lake (Upper New Hope) portion of Town, the historical loading caps are 2.2 lb/ac/yr nitrogen and 0.82 lb/ac/yr phosphorus, with the 1-year 24-hour peak-flow no-net-increase rule and the first-inch runoff treatment rule held in abeyance pending state rule readoption — but the Stage I retrofit requirement remains in effect, and the Town requires SCM design plans through the Stormwater Field Services group. Riparian buffers under 15A NCAC 02B .0267 (Jordan Lake) remain mandatory: a 50-foot riparian buffer is measured from the top-of-bank of all intermittent and perennial streams in the Jordan Lake watershed, with the inner 30 feet treated as Zone 1 (most restrictive) and the outer 20 feet as Zone 2. The Neuse buffer rule 15A NCAC 02B .0233 imposes a similar 50-foot buffer in the Neuse River Basin. Submit drainage studies and SCM plans to Apex Stormwater Field Services at (919) 362-8166 in parallel with the building permit.