Cost-benefit analysis can significantly aid the decision-making process for flood risk reduction and mitigation. Decision-makers can use it to weigh the expenses of various flood mitigation strategies against their possible upside in terms of lowering the risk of losses and damage. Decisions regarding how to allocate resources for flood risk management can be made more intelligently with the use of this information by policymakers and stakeholders. During severe rainfall or snowfall, these rivers are prone to flooding, which can harm structures such as homes, businesses, and infrastructure, have negative impacts to land uses and as a result they can cause high opportunity costs. Flooding in the Thrace region can have indirect and direct expenses, including property damage and lost commercial activity. These costs can include communication breakdowns and higher insurance rates. The predicted total economic losses from erosion for all of Greece are €356 million and €649 million for a 0.5- and 1-meter sea level increase, respectively.