The use of digital twins allows to simulate various scenarios, optimize production processes, predict risks, improve operational control, manage oil and gas production. At the same time, the use of digital twins is inexpedient without optimization technologies integrated with data delivery and processing algorithms, feedback algorithms with dispatch systems and developed business logic for pumping and production operational control. Physical and mathematical modeling, optimization methods and machine learning algorithms are used to solve integrated optimization problems. For efficient management of the reservoir pressure maintenance system, it is necessary to carefully select candidates for conversion to injection and injection modes for each injection well. To solve such problems, it is necessary to use a full-mass integrated model with geological-hydrodynamic modeling (GHDM) approaches as the reservoir component. However, in most cases, the use of full-scale GHDM is difficult in assets with a large fund volume and requires increased labor costs to ensure creation and update of such models. To solve this problem, we developed technologies for modeling unsteady flows in the reservoir, based on the use of a pseudo-function model for three-phase filtration calculation, as well as algorithms for automated adaptation of reservoir models to the actual operation data. The implemented modeling algorithms were integrated into a functional-technical land-scape containing data validation and verification algorithms, technologies for continuous updating of the digital reservoir twin, analysis of all production and injection wells. This solution was tested at one of the Western Siberian fields to optimize water injection and achieve the target oil production potential. Based on the results of the work, candidates were selected for transfer to the injection well stock and optimal well operation modes were selected by adjusting water injection rates and connection diameters at production wells. During pilot operation, group optimization of wells helped to balance the wells’ load, the load of pipeline system, oil and water treatment facilities. Also, oil production at wells was increased.