The planned pace of sustainability in the McMullin Area will provide early flexibility

The SGMA requires subbasins to become sustainable by 2040. Reaching sustainability objectives will not occur overnight, but rather will require the laying of a foundation at the onset of implementation that yields results in groundwater conditions over the entire 20 year stabilizing period and the 50 year planning horizon. As MAGSA takes stock of current groundwater conditions, the Board must consider the rate at which mitigation will occur.

The orderly implementation of sustainability efforts needs to strike a balance between practicality and intensity. Identified in the Groundwater Sustainability Plan (GSP), the planned rate of mitigation must be approved by Department of Water Resources (DWR). The planned rate needs to set forth a path to achieve sustainability objectives on a feasible timeline.

MAGSA’s technical consultant Lynn Groundwater, Provost & Pritchard, reviewed three alternatives for the rate of mitigation: a constant rate, a phased rate, and a deferred rate. Constant mitigation sets an even pace of 25% improvement every 5 years toward the sustainability objectives. This option is likely acceptable to DWR, but may not be practical as initial projects and management actions will take time to develop. A phased mitigation schedule starts more slowly initially, with an increased rate of progress over time. This rate would allow time to develop management actions and build projects that may not yield the bulk of the intended results until further down the implementation timeline. Deferred mitigation delays 100% of improvement to the last 5 years of GSP implementation, leaving all progress to occur between 2035 and 2040. This rate is unlikely to be accepted by DWR.

The best fit for MAGSA’s sustainability timeline appears likely to be a phased mitigation schedule. Laying the foundation for the service area’s groundwater management will mean heavy lifting on the front end of the timeline to develop the nuts and bolts of projects and management action mechanisms. Phased mitigation grants flexibility to establish this foundation that will yield increased results in later implementation years.