In prolific gas reservoirs with strong aquifer drive, water coning is often the determining factor in well productivity and ultimately, gas recovery factor. One of the main drivers in optimising the field development in these cases is to reduce the drawdown of the wells and consequently, a horizontal well design is often used. It is the case, however, that in such highly permeable gas fields extending the horizontal length beyond 1000-2000 ft often does not help to improve well productivity any further, as well bore friction becomes the constraining factor. This paper presents a cost effective and simple solution to increase well productivity by 60% compared to single horizontals at a marginal cost increase. A simple level-1 dual lateral with large bore casing-flow well design has shown to be able to deliver the additional productivity at only a 5-10% incremental increase in cost. Furthermore, we present the results of the numerical simulation that helped to justify the well design and to deal with interference between the branches.

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