The temperature and surface geophysical data contained in this release have primarily been collected to support groundwater/surface water methods development, and to characterize the hydrogeological controls on native brook trout habitat. All data have been collected since 2010 along the Quashnet River corridor located on Cape Cod, MA, USA. Cape Cod is a peninsula in southeastern coastal Massachusetts, USA, composed primarily of highly permeable unconsolidated glacial moraine and outwash deposits. The largest of the Cape Cod sole-source aquifers occupies a western (landward) section of the peninsula, and is incised by several linear valleys that drain groundwater south to the Atlantic Ocean via baseflow-dominated streams. Strong groundwater discharge to the Quashnet River supports a relatively stable flow regime, as monitored by USGS gage 011058837, located at the downstream end of typical field research focus areas. The lower Quashnet River emerges from a narrow sand and gravel valley to a broader area with well-defined lateral floodplains. Historical cranberry farming practices, abandoned in the 1950s, have modified the stream corridor as described by: Barlow, P. M. and Hess, K. M.: Simulated Hydrologic Responses of the Quashnet River Stream-Auquifer System to Proposed Ground-Water Withdrawals, Cape Cod, Massachusetts, U.S. Geol. Surv. Rep. 93-4064, 51, 1993. The Massachusetts Division of Fisheries and Wildlife has been monitoring brook trout populations in the Quashnet River since 1988 and movement since 2007. Groundwater influence on stream temperature is pronounced, particularly over the 2-km reach above the USGS gage, below which stream stage is tidally affected.

Surface geophysical tools remotely sense hydrogeological properties that can control subsurface flow and water quality. There are numerous geophysical tools, for the Quashnet River work we have principally used ground penetrating radar (GPR) and electromagnetic imaging (EMI). The instruments are either hand carried or floated down the stream channel and other cross-sections of the river corridor. Data from various field deployments of GPR and EMI are described and presented here.

Surface geophysical tools remotely sense hydrogeological properties that can control subsurface flow and water quality. There are numerous geophysical tools, for the Quashnet River work we have principally used ground penetrating radar (GPR) and electromagnetic imaging (EMI). The instruments are either hand carried or floated down the stream channel and other cross-sections of the river corridor. Data from various field deployments of GPR and EMI are described and presented here.

Heat is used as a tracer for a variety of physical hydrogeological process. Several types of instruments are used to measure the temperature of surface water and saturated sediments. In the Quashnet River we have been using methods that include: infrared, individual logging thermistors, and fiber-optic distributed temperature sensing. The latter type of data (FO_DTS) are described and presented here.

Heat is used as a tracer for a variety of physical hydrogeological process. Several types of instruments are used to measure the temperature of surface water and saturated sediments. In the Quashnet River we have been using methods that include: infrared, individual logging thermistors, and fiber-optic distributed temperature sensing. The latter type of data (FO_DTS) are described and presented here.

Heat is used as a tracer for a variety of physical hydrogeological process. Several types of instruments are used to measure the temperature of surface water and saturated sediments. In the Quashnet River we have been using methods that include: infrared, fiber-optic distributed temperature sensing, and individual logging thermistors. The latter type of data (thermistor) are described and presented here.

Heat is used as a tracer for a variety of physical hydrogeological process. Several types of instruments are used to measure the temperature of surface water and saturated sediments. In the Quashnet River we have been using methods that include: infrared, fiber-optic distributed temperature sensing, and individual logging thermistors. The latter type of data (thermistor) are described and presented here.

Heat is used as a tracer for a variety of physical hydrogeological process. For ongoing studies related to groundwater/surface water exchange, temperatures of streambed sediment along the bank, in drainage ditches, and in the river were measured using handheld thermal infrared (FLIR Systems, Inc) cameras and thermocouple (Digi-Sense, Inc) probes. Thermal surveys of the Quashnet river were completed from August 14 to August 25, 2017. Zones of spatially-preferential groundwater discharge were identified as cold anomalies in summer, reflecting the influence from groundwater temperatures of approximately 11 degrees Celsius.

Heat is used as a tracer for a variety of physical hydrogeological process. For ongoing studies related to groundwater/surface water exchange, temperatures of streambed sediment along the bank, in drainage ditches, and in the river were measured using handheld thermal infrared (FLIR Systems, Inc) cameras and thermocouple (Digi-Sense, Inc) probes. Thermal surveys of the Quashnet river were completed from August 14 to August 25, 2017. Zones of spatially-preferential groundwater discharge were identified as cold anomalies in summer, reflecting the influence from groundwater temperatures of approximately 11 degrees Celsius.

In summer in Massachusetts, USA, preferential groundwater discharge zones are often colder than adjacent streambed areas that do not have substantial discharge. Therefore, discharge zones can efficiently be identified and mapped over space using heat as a tracer. This data release contains fiber-optic distributed temperature sensing (FO-DTS) data collected along the streambed interface of the main channel and tributaries of the upper Quashnet River, within approximately 1 km of Johns Pond, from June 14 to June 20, 2020. For these deployments a Salixa XT-DTS control unit (Salixa Ltd, Hertfordshire, UK) was used, and measurements were made over several day increments at 0.508 m linear resolution. Specific locations for collected data are located within the data files, and additional details are contained in the ‘readme’ files within each zipped data directory. Measured data in the form of Salixa instrument files are located in the 'Raw' data directory, including data collected along lengths of optical fiber that were not installed in the streams. The 'Processed' data directory contains data that have been aggregated from the original machine output files, spatially trimmed, and georeferenced. Additionally, simple summary streambed interface temperature statistics (mean, max, min, standard deviation) are listed by streambed location.