An EQUATOR helicopter-borne AEM survey (∼1,500 line-km, 200 m spacing) over the Muravera coastal plain (Flumendosa delta, SE Sardinia) produced a quasi-3D resistivity volume that refines hydrostratigraphy and informs groundwater management. The AEM model maps discontinuous shallow conductive horizons (1–10 Ω•m) interpreted as lagoonal silts/clays or brackish deposits, moderately resistive phreatic alluvium (10–50 Ω•m), and more resistive gravelly/coarse alluvial axes (≈30–150 Ω•m). Crucially, it delineates a laterally extensive deep conductive lagoonal clay unit (≈0.5–5 Ω•m) acting as an aquitard, previously inferred only from sparse boreholes. Resistivity patterns support a pathway-controlled salinization model, with discontinuous conductive bodies and preferential-flow corridors (paleochannels, river mouths, foxi, abstraction-driven upconing) rather than a uniform seawater wedge. For management, AEM results delineate salinity-prone domains, identify transmissive coarse bodies that can propagate drawdown and salinity, and indicate areas where small head changes yield large salinity responses. The survey prioritizes locations for targeted follow-up (TEM, ERT/IP, borehole logging, hydrochemistry, head-EC monitoring) and recommends calibrated, uncertainty-aware integration with borehole and petrophysical data to support vulnerability zoning, monitoring design, and abstraction scenarios.