North Fork Kings GSA joins regional agreement to monitor land subsidence
At the July 22nd Board Meeting, the North Fork Kings GSA approved a cost-sharing agreement between Groundwater Sustainability Agencies (GSAs) in both the Kings and Tulare Lake Subbasins for subsidence monitoring. The Kings River Conservation District (KRCD), a regional special district with diverse water resources management roles, proposed the agreement to support the Subbasins’ monitoring efforts under the Sustainable Groundwater Management Act (SGMA).
Because declining groundwater levels can cause surface elevations to lower, subsidence is an indicator of groundwater sustainability under SGMA. Over time subsidence may lead to what SGMA terms an “undesirable result”, for example damage to infrastructure like canals or roadways. Consistent monitoring across the region is key to preventing significant rates of subsidence from causing undesirable results.
The cooperative agreement approved by the North Fork Kings GSA provides funding to increase both the magnitude and frequency of KRCD’s subsidence monitoring program. Established in 2010 with surveys conducted every 2-5 years at 125 monuments, the current monitoring is too infrequent to meet SGMA’s needs for reporting on subsidence conditions and critical data gaps exist in the network. The agreement will allow KRCD to conduct surveys annually and establish an additional 71 network monuments that fill known data gaps.
Subsidence data collected by KRCD over the years was used in the development of the North Fork Kings GSA’s Groundwater Sustainability Plan (GSP) and has been referenced by GSAs as a source for mandatory SGMA reporting to the State. Cooperating with KRCD and the GSAs is a cost-effective solution to bring robust data to the table for successful groundwater management.
The agreement outlines cost-sharing of 8% between eleven GSAs in the two subbasins, while KRCD will contribute 12% to the overall cost. The cost for 2020 monitoring is estimated in the agreement not to exceed $30,000. The South Fork Kings GSA and Southwest Kings GSA, both located in the Tulare Lake Subbasin, have approved the agreement. The remaining GSAs are currently considering approval.