Local Soil Conditions: Wando and Lakeland soil series are the primary upland soils in the Myrtle Beach area — excessively drained, deep Entisols with fine to medium sand throughout the profile. These soils offer excellent percolation (less than 3 minutes per inch in many locations) but minimal treatment capacity for nutrients and pathogens. Closer to tidal creeks, the Waccamaw and Paxville soils — poorly drained, organic-matter-rich Ultisols and Histosols — have water tables within inches of the surface and cannot support conventional drain fields.
Water Table: Upland Wando soils have water tables at 5–10 feet on barrier island ridges and inland terraces. However, proximity to the coast means tidal fluctuations influence groundwater elevation within 0.5–1 mile of tidal waters, and storm surge events can temporarily elevate water tables across wide areas. Low-lying pocosins and Carolina bay wetlands throughout Horry County maintain near-surface water tables year-round.
Climate Impact: Myrtle Beach has a humid subtropical climate with hot, humid summers and mild winters. Annual rainfall averages 52 inches with a summer peak from June through August driven by afternoon thunderstorms and tropical weather. Hurricane season (June–November) is a major concern — Horry County has experienced significant septic system damage from multiple landfalling storms including Floyd (1999), Matthew (2016), and Florence (2018), which caused prolonged flooding across the county's flat coastal plain.