Hydropower has the ability to play a critical role in curbing climate change because of the carbon free services it provides with its large storage capacities and fast ramping rates to complement the intermittency and uncertainty of other renewable energy resources. However, models used for energy system management and planning, largely, do not comprehensively include water avail ability or environmental information, which can lead to improper representations of water-energy interlinkages. In addition, there exists a substantial gap in the general availability and quality of regional and global data across different fields, where information is stored using non-standardized data formats. These challenges make it difficult for current and emerging hydropower energy management technologies to leverage a large amount of available information to enhance the efficiency of hydropower operations. This project will design, validate, and develop the Open Hydropower Data Protocol (OHDP), an open protocol enabling different systems and cloud-based applications to interact with each other in order to easily access the necessary information that supports hydropower operation. OHDP will consolidate, in a unified data structure, different types of information such as environmental (e.g., precipitation), forecasts (e.g., water inlet, electricity demand), hydropower plant (e.g., tur bine speed, reservoir level), and power grid (e.g., power network topology). The open protocol includes methods to exchange data and adhere to system authentication schemes while also providing modules to promote seamless integration into existing proprietary systems. OHDP improves semantic interoperability between hydropower energy management systems (EMS) and industrial data acquisition companies. During Phase I, Grid Elevated will develop the core architecture of OHDP, with its main functionalities, data structure, and exchange, analysis, and authentication methods. The preliminary feasibility studies and proof of concept will be developed using the AVEVA PI System and a DOE award-winning hydropower operation optimization software, HydroFlex, which is able to manage hydropower units by integrating power and water data. In addition, the project team will perform the initial market research and commercialization plan. OHDP is expected to have widespread applications for hydropower operators, and it will directly impact the efficiency and reliability of electricity generation and water quality. Water spills result in hundreds of millions of dollars in lost hydropower generation. OHDP will help to decrease water spillage by enabling standardized access to the necessary data to optimize hydropower generation. In addition, the energy flexibility market is expected to account for $10 billion dollars by 2029, where about 30% corresponds to hydropower generation; OHDP will support strategies seeking to capitalize on the growing flexibility market.