Secondary recovery by water injection is one of the most popular methods to increase reservoir pressure and sweep efficiency in the industry. It is a cost effective technology in reservoirs such as Shushufindi field, where water, energy and sink points are easily available. This pilot aims to provide proof of concept of water injection in mature Ecuadorian fields. The water injection pilot project was carried out in the central north area of the field, in the lower U reservoir, selected as the target injection horizon due to pressure depletion. The injection started in December 2014 in SHS-246D and SHS-244D and then in 2015 two more injector wells were set up, SHS-247 & SHS-003. These wells are located in a 125 acres area, based on inverted five spot pattern. Secondary projects around the world have shown that the success of any water injection project is based on an exhaustive monitoring and surveillance process, along with using the many analysis tools and plots available. Shushufindi, however, needed a specific tailored toolset that fits the surface operating conditions, one that is able to monitor the variables required to understand the local reservoir hydraulic behavior, minimizes issues in the injection cycle, and provides quality data for the continuous improvement of the water injection pilot. In order to achieve this objective, some variables were selected and recorded in a group of theoretical plots. This was achieved by developing a series of workflows on a production management software platform, centered on an alert system to rapidly identify changes in the monitored injection variables and to respond if needed. This monitoring system allows a quick identification of well plugging issues in injector wells through the use of Hall plots, it also tracks the water quality at different points in the water processing plant allowing adjustments to made to the process to improve the water quality if needed, provides information for reservoir characterization monitoring, Voidage Replacement Ratio (VRR), and determines the water injection response in producer wells by monitoring the production parameters.

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Most of the fields in Ecuador are considered "mature." Water injection is a well-known solution for mature fields. Water injection projects require a source of clean water. Traditionally, minimum specifications are achieved by surface treatment facilities. However, in the Ecuadorian Oriente Basin, the Hollin reservoir is an active aquifer with water meeting the requirements for use in waterflooding. But in other cases, water from production wells and from traditional surface facilities requires high investment costs because of associated facilities, chemical treatments, water production lines, and other requirements. A novel completion design has been developed. This proposed completion is called "modified dumpflooding" and represents a cost-effective solution for Ecuadorian mature fields. Dumpflooding is a modified version of dual concentric completion using most of its configuration pieces. It also takes advantage of extensive local experience in dual concentric completion design. Modified dumpflooding completion enables companies to use just one well for water production, injecting it into the depleted reservoir as a closed loop. Additionally, it helps to save costs in surface facilities by reducing human exposure to high pressure lines over large distances and eliminating operational expenditures for chemicals and equipment maintenance. Nodal analysis is foundational to helping companies understand how current design of waterflooding projects is behaving. It also provides a basis for mechanical configuration optimization to reduce bottlenecking points and improve completion performance.