## 5 Conclusions  
Spectral indexes applied to medium resolution satellite images over a wide time frame can help in monitoring the effects of the receding waters on archaeological sites. The NDWI can distinguish between water and land surfaces in a useful way, allowing us to understand when a specific area is out the water or not. Applying the index on different images over time and by quantifying the results of the pixel analysis, it is possible to highlight years with very low or high water levels, with results partially comparable with the Global Surface Water (GSW) dataset [94] (Figure 3e), but also sites that resurfaced more often than others during the considered time frame. Knowing which sites are more likely to emerge can prove useful, because it is likely that these sites will resurface again if there is a decrease in water level in the reservoirs. This, in turn, can help in planning future targeted investigations. In fact, by knowing in advance which sites are more likely to emerge from the ebbing waters, salvage surveys, targeted excavations, or assessments of the site's conditions can have a more precise lead. On the other hand, knowing the number of emensions and coupling this information with the site status before its flooding (e.g., the type of archaeological evidence recorded) will help in a preliminary assessment of the site status before any future investigation. The present methods and results, together with the difference between the single pixels and the zonal histogram analysis, also highlight the importance of accurate field recording of the extent of archaeological materials, and the need for more accurate and available geospatial data for archaeological sites. Moreover, field campaigns will help not only the cultural heritage management, but also the validation of the results. In the end, the methodology presented here has the advantage of being easy to reproduce and apply to different areas, but also easily accessible by being based on free software and easy to access data, if we exclude archaeological sites data. In fact, the NDWI reclassification and analysis is faster and easier to reproduce than more in-depth methodologies such as the GSW, while still yielding promising results. Moreover, this approach can set a starting point to address a hitherto missing element of many salvage projects, i.e., the evaluation of the post-flooding impact of reservoirs on cultural heritage. In fact, apart from a few examples that inspired the development of this methodology [22; 23], submerged sites have been considered mostly lost. However, it is clear that, at least for the lakes presented in this study, this may not always be the case. Lastly, it has been already highlighted how costs, availability, and ease of access to commercial satellite images for the Near East are still a major hindrance for any research aimed at monitoring the archaeological cultural heritage, and how archaeologists had to cope with these restrictions in different ways (see, e.g., [PERSON] et al., 2020) and related bibliography). In this sense, the daily availability of Sentinel-2 images and the possibility to monitor archaeological sites frequently, prove that these satellites images are and will be among the most useful free tools in any future remote sensing application. **Supplementary Materials:** The following are available online at [[https://www.mdpi.com/2072-4](https://www.mdpi.com/2072-4)]([https://www.mdpi.com/2072-4](https://www.mdpi.com/2072-4)) 292/13/4/786/s1, Figure S1: Temporal coverage of satellite images used in the analysis; Figure S2: Emersion rate of archaeological sites in the Haditha Dam; Figure S3: Emersion rate of archaeological sites in the Mosul Dam; Figure S4: Emersion rate of archaeological sites in the Hamrin Dam.