On-Call Groundwater Hydrologist for Soquel Creek Water District

Soquel Creek Water District has renewed the on-call contract four times as it makes progress toward groundwater sustainability.

OVERVIEW

Previously HydroMetrics, and now M&A, has supported Soquel Creek Water District (SqCWD) on various groundwater management and well projects. These project include development and implementation of a Groundwater Management Plan; recommendations for its monitoring network; Well Master Plan Environmental Impact Report (EIR) including installation of new production wells; monitoring and adaptive management programs for Soquel Creek and private wells; cooperative groundwater management agreements with neighboring water agencies; protective elevations for preventing seawater intrusion; recharge estimates for evaluating sustainable yield; and modeling, groundwater hydrology support for the EIR and permitting, and well design and installation for the Pure Water Soquel project.

SERVICES

Well Siting

  • For SqCWD’s Well Master Plan, M&A helped site five new production wells, which are located and designed to reduce seawater intrusion by moving pumping away from the coast and to minimize well interference problems.
  • M&A developed pumping distributions that the District could use to meet different demand scenarios while sustainably managing the basin.
  • The anticipated impacts from the distribution of pumping at the new and existing wells were analyzed and incorporated into the project EIR.

Well Installation and Testing

M&A has installed three municipal production wells for the District, ranging from to 595 to 670 feet deep. M&A was responsible for all aspects of the well design, installation, and testing of the municipal wells including:

  • Permitting and utility coordination, adhering to all regulatory requirements
  • Assisting with bidding and bidder selection
  • Construction management

Additionally, M&A has installed numerous monitoring wells for the District, at depths of up to 920 feet. These wells monitor seawater intrusion and provide independent monitoring data for adjacent production wells. M&A was responsible for all aspects of the well design, installation, and testing of the monitoring wells.

M&A is currently implementing SqCWD’s Pure Water Soquel program to recharge purified water in order to prevent seawater intrusion and achieve sustainability. M&A is leading multiple activities including design and installation of two new recharge wells; destruction of an inactive municipal well; and installation of 10 associated monitoring wells. These tasks include:

  • Preparation of preliminary designs
  • Preparation of technical specifications
  • Contractor bid support
  • Construction management services
  • Reporting

Tracer Testing and Spinner Logs

As part of the District’s ongoing well maintenance program, M&A has conducted dye tracer studies to identify depth-specific well yields. These data are combined with depth-specific groundwater quality sampling and spinner logging to reveal how well yields and groundwater quality are distributed with depth. This information was used to develop well-specific criteria for well modification or well destruction. M&A is also planning the tracer study for startup of recharge of purified water as part of permitting requirements for the Pure Water Soquel project.

Well Efficiency and Aquifer Testing

M&A helps the District track well performance as part of its ongoing well maintenance program. Tracking declines in specific capacity have helped alert the District to when wells need redevelopment. Aquifer testing has also helped plan sustainable pumping rates and assisted the District with treatment plant design.

Well Rehabilitation

M&A has managed the redevelopment of five municipal wells for the District. The redevelopment includes physical redevelopment by brushing, overpumping, and surging/swabbing combined with depth-specific air lifting to remove fine particulate matter. The physical redevelopment is followed by chemical redevelopment to remove iron bacteria and dissolve possible encrustations. M&A is also leading the rehabilitation of an existing recharge well for the Pure Water Soquel program.