This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1111/gwat.12918 Case Study/ Simulation of Flow in a Complex Aquifer System Subjected to Long- term Well Network Growth Hua-Sheng Liao Department of Civil and Environmental Engineering, Michigan State University, 428 S. Shaw Lane, East Lansing, MI 48824; hliao9809@gmail.com Zachary K Curtis Department of Civil and Environmental Engineering, Michigan State University, 428 S. Shaw Lane East Lansing, MI 48824; curtisza@ msu.edu Prasanna Venkatesh Sampath Civil Engineering, Indian Institute of Technology Tirupati, India; prasvenk@iittp.ac.in Shu-Guang Li, Corresponding author: Department of Civil and Environmental Engineering, Michigan State University, 428 S. Shaw Lane, East Lansing, MI 48824; 517 432 1929; lishug@egr.msu.edu Conflict of interest: None Keywords: aquifer sustainability; groundwater model parameterization; water well datasets; transition probability geostatistics; Article Impact Statement: We develop and apply an approach for modeling complex aquifer systems subject to long-term distributed pumping dynamics Abstract In west-central Lower Peninsula of Michigan, population growth and expanded agricultural activities over recent decades have resulted in significant increases in distributed groundwater withdrawals. The growth of the extensive well network and anecdotes of water shortages (dry wells) have raised concerns over the region’s groundwater sustainability. We developed an unsteady, three-dimensional (3D) groundwater This article is protected by copyright. All rights reserved.