圣安东尼奥供水系统（SAWS）目前正在建设含水层蓄水库和 德克萨斯州贝克斯县南部的回收（ASR）井场。对于高级规划、设计， 此外，还需要一种先进的地下水建模工具来评估油井的影响 井场内及周边区域的现场作业。 该井场位于比克斯县南部的一个三角形地块上，靠近 这三个县与阿塔斯科萨县和威尔逊县交界处。在buildout， SAW将有34口ASR井和6口生产井。这些井的深度约为500米 英尺至800英尺，油井产量高达每分钟3500加仑（gpm）。详细的地球物理和地球化学信息 收集钻孔测井数据，确定岩性接触，并进行广泛的含水层测试 该计划在所有油井的施工期间实施。因为卡里佐含水层 它是最高产的含水单元，是ASR和生产的目标地层 威尔斯。该项目开发了含水层系统的MODFLOW1地下水模型 地区最初的四层ASR模型设计（代表皇后城、雷克劳、卡里佐和 威尔科克斯地层）最终扩展到六层，以代表当地公认的 Carrizo地层内的水文地质分区（上部Carrizo、块状Carrizo、下部Carrizo） 卡里佐）。所有的ASR井都在巨大的Carrizo中进行了筛选，因此形成了三层结构 Carrizo细分更准确地反映了井场作业和油井性能。 一个332行393列的有限差分网格由200个网格组成- 脚 井场附近的方形单元，向边缘扩展到1000英尺见方的单元 模型域的。井场的200英尺间距允许所有现有和计划的ASR 要准确地描绘油井。因为该模型的主要目的是模拟ASR 在运行期间，校准集中在复制在试验期间进行的含水层试验 ASR井的开发。流入各模型层的水包括露头和跨地层的一次补给 在深处流动。每个模型层的流出可能包括油井泵送、排放至 河流、流经模型边界的水流和跨地层水流。所有层都被表示出来 这样，地层的承压和非承压（露头）部分的流动都是真实的 模拟的。所有层的东风和西风侧边界以及下倾边界均选择了总水头边界（GHB）MODFLOW包。GHB是 也用于最上面活动层的顶部，以表示地下水位的影响 斯巴达和皇后城上空其他年轻编队的情况。MODFLOW well软件包也被用来表示通量边界条件。“背景”页面来自 模型域内的Carrizo是概念模型的主要排放物，因此 包含对于该模型表示当前条件很重要。莫德弗尔河 该软件包被用来代表阿塔斯科萨河和圣安东尼奥河的露头 模型层。这两条溪流在模型区都略有增加，尽管它们与该区域相邻 西南部位于弗里奥河和努埃塞斯河流域，那里的水流条件普遍流失。包括数字。

The San Antonio Water System (SAWS) is currently constructing an aquifer storage and recovery (ASR) well field in southern Bexar County in Texas. For advanced planning, design, and operations, an advanced groundwater modeling tool is needed to assess the effects of well field operations within the well field and in the surrounding area. The well field is located on a triangular section of land in southern Bexar County, near the three-county corner junction with Atascosa and Wilson Counties. At buildout, SAWS will have 34 ASR wells and 6 production wells. The wells range in depths from about 500 ft to 800 ft and well yields range up to 3,500 gallons per minute (gpm). Detailed geophysical and boring log data were collected, lithologic contacts were identified, and an extensive aquifer test program was carried out during the construction of all the wells. Because the Carrizo aquifer is the most productive water-bearing unit, it is the target formation for the ASR and production wells. A MODFLOW1 groundwater model of the aquifer system was developed in the project area. An initial four-layer ASR model design (representing Queen City, Reklaw, Carrizo, and Wilcox Formations) was ultimately expanded to six layers to represent the locally recognized hydrogeologic divisions within the Carrizo Formation (upper Carrizo, massive Carrizo, lower Carrizo). All of the ASR wells and are screened in the massive Carrizo, thus the three-layer Carrizo subdivision more accurately represents well field operations and well performance. A finite difference grid of 332 rows and 393 columns was constructed with 200-foot square cells in the vicinity of the well field, expanding to 1,000-foot square cells toward the edges of the model domain. The 200-foot spacing in the well field allows all existing and planned ASR wells to be accurately represented. Because the primary purpose of the model is to simulate ASR operations, the calibration concentrated on replicating aquifer tests conducted during the development of ASR wells. Inflow of water to each model layer includes primary recharge at the outcrop and cross-formational flow at depth. Outflow in each model layer may include well pumpage, discharge to rivers, flow through the model boundaries, and cross-formational flow. All layers are represented such that flow in both the confined and unconfined (outcrop) parts of the formation is realistically simulated. The General Head Boundary (GHB) MODFLOW package was selected for all layers for both easterly and westerly lateral boundaries as well as the downdip boundary. The GHB was also used for the top of the uppermost active layer to represent the influence of water table conditions in the Sparta and other younger formations above the Queen City. The MODFLOW well package was also used to represent flux boundary conditions. "Background" pumpage from the Carrizo within the model domain is a major discharge from the conceptual model, so its inclusion is important for this model to represent current conditions. MODFLOW's river package was used to represent the Atascosa River and San Antonio River in the outcrop of each model layer. Both streams are slightly gaining in the model area, though they abut the region to the southwest in the Frio and Nueces River basins, where losing stream conditions are prevalent. Includes figures.