Lavaş Lake is a shallow wetland system located southwest of Lake Çıldır in the Arpaçay district of Kars Province. Its shores are surrounded by reed beds, and the lake provides a natural habitat for birds. In 2019, Lavaş Lake was declared a “Strictly Protected Sensitive Area”. However, the risk of drying, which has been associated with the diversion of its water to Lake Çıldır, makes it necessary to examine changes in the lake’s water regime and the possible role of anthropogenic hydromorphological interventions. The aim of this study is to evaluate the water regime changes observed in Lavaş Lake Wetland in relation to hydromorphological interventions and climatic conditions, based on long-term changes in open-water surface area, surface moisture, and wetland vegetation. For this purpose, Landsat 5, 7, 8, and 9 Collection 2 Level-2 satellite images with 30 m spatial resolution for the 1984–2025 period were processed in Google Earth Engine (GEE). Images from the April–July period were combined annually, and cloud/shadow effects were reduced to generate representative images for each year. Using these data, open-water surface area was assessed with the Modified Normalized Difference Water Index (MNDWI), surface moisture with the Normalized Difference Moisture Index (NDMI), and wetland vegetation indicators through the combined use of NDMI and the Normalized Difference Vegetation Index (NDVI). To evaluate the geomorphological characteristics of the study area, the Copernicus digital elevation model with 30 m spatial resolution was used. Based on this dataset, the morphology of the lake basin, slope conditions, and drainage connections were examined. In addition, climatic conditions were evaluated using precipitation, potential evapotranspiration (PET), the Palmer Drought Severity Index (PDSI), and snow water equivalent (SWE) data for the preceding winter period obtained from the TerraClimate dataset. Preliminary findings indicate that the open-water surface area of Lavaş Lake Wetland has decreased markedly over the long term. According to the MNDWI-based analysis, the historical maximum open-water candidate area was determined as 53.25 ha, whereas the open-water surface area declined to 5.23 ha in 2025. This corresponds to a decrease of approximately 90.18%. In contrast, the NDMI-based surface moisture area was calculated as 200.48 ha in 2025, while the wetland vegetation indicator covered 194.09 ha. These results suggest that although the open-water surface of the lake has contracted substantially, the moist surface and vegetated wetland character of the area has not completely disappeared. Preliminary assessments based on climatic data show that the long-term decrease in open-water surface area does not have a direct and strong relationship with April–July precipitation totals or with the water balance indicator derived by subtracting potential evapotranspiration from precipitation (P–PET). In contrast, the clearer relationships between surface moisture and wetland vegetation indicators and April–July precipitation and P–PET values suggest that moisture conditions in the area are more responsive to seasonal climatic conditions. Overall, these findings indicate that the observed open-water loss in Lavaş Lake cannot be explained solely by seasonal drought; rather, the morphology of the lake basin, drainage connections, and possible anthropogenic hydromorphological interventions may have played an important role in this change.