Managing and allocating groundwater resources. Natural groundwater resources are subject to steadily increasing water demand for agriculture, domestic and industrial use. ... Groundwater models meant to reflect such strategies require a high level of local detail on a regional scale. OCWD captures surface water from several sources. Water is collected and contained, then added to the groundwater basin to recharge it. Recharging is a natural hydrological process. Water moves down from the surface into the groundwater basin to replenish the aquifer. Surface Water and Groundwater. (Are they connected?) Examples of surface water include creeks, lakes and streams. Surface water is found above the earth's surface. Surface water can be contaminated by rainwater runoff from homes, businesses, roads and parking lots. Groundwater will eventually come back to the surface, discharging to streams, springs, lakes, or the oceans, to complete the hydrologic cycle. Groundwater Zones. ... Aquifer and Well Types. ... Flow Rate. ... Recharge. ... Well Interference. ... Groundwater Mining. ... Subsidence.