The 1706 eruption of Montaña Arenas Negras at Garachico, had important implications for volcanic hazard prediction. Tenerife is part of the Canary Islands and exhibits a complex eruptive history with both effusive and explosive events. Garachico–1706, geochemically is under studied. The eruption was significant due to its destruction of the port city and its location on the high-risk Northwest Rift Zone (NWRZ). Fieldwork conducted in December 2023 collected lava samples across various lava flows. Geochemical analysis revealed a range of alkali-rich lavas from tephrite to phonolitic tephrite, with evolving silica and alkali content over time. Evidence suggests the eruption progressed through multiple stages, indicating magma evolution. When compared with the well-documented 2021 Tajogaite eruption on La Palma, which showed hybrid-Strombolian behavior at VEI 3, Garachico–1706’s geochemistry showed similar trends. Institutional analysis revealed systemic weaknesses in volcanic risk communication within the Canary Islands' emergency response structure (PEVOLCA), particularly during the 2021 eruption. Recommendations include improved coordination between scientific bodies (IGN, INVOLCAN) and transparent public communication strategies. This research enhances understanding of rift-related volcanism in oceanic islands and underscores the value of integrating geochemical analysis, eruption history, and risk modeling to inform future eruption forecasts and emergency planning on Tenerife.