Cryptosporidium Synoptic Study of the Raritan River Basin
The USGS New Jersey Water Science Center is partnering with New Jersey American Water (NJAW) on a project in the Raritan River Basin Study area to investigate the potential sources of Cryptosporidium in the Raritan River Basin.
Cryptosporidium (Crypto) is a protozoan parasite of both domestic and wild animals that has been identified as a pathogen of concern and is considered a leading cause of waterborne disease among humans in the United States. Crypto may be introduced to waterbodies failing or improperly connected septic systems and wastewater infrastructure, agricultural lands, wildlife inputs, and runoff. Potential human health risks have been noted for those using the Raritan River Basin because of pathogen exposure for recreational activities. The Raritan River is also a source for drinking water therefore elevated levels have impacts for water treatment.
The USGS New Jersey Water Science Center is partnering with New Jersey American Water (NJAW) on a project in the Raritan River Basin Study area. The objective of the project is to investigate the occurrence and potential sources of Cryptosporidium from multiple rivers and tributaries to the main steam Raritan River.
Phase 1
Phase 1 of the Raritan River Basin Cryptosporidium investigation focused on establishing the presence, spatial distribution, and variability of Cryptosporidium across six key sites in the basin. Initial findings show that Cryptosporidium was present throughout the system, with concentrations and sources influenced by both spatial and temporal factors. Findings from this phase will support broader efforts by New Jersey American Water (NJAW), the U.S. Environmental Protection Agency, and other partners to identify potential environmental and anthropogenic contributors to microbial contamination within the watershed. The initial findings from Phase 1 were used to identify sampling areas and strategies for Phase 2.
Data and insights from Phase 1 are being compiled into a Scientific Investigations Report (SIR), which will provide comprehensive detail on contamination patterns, temporal trends, and potential upstream source locations. This report will inform management actions and assist their ability to perform targeted remediation of microbial contamination in the Raritan River Basin.
Phase 2
Phase 2 of the project focused on the Peters Brook sub‑basin, where Phase 1 results indicated elevated Cryptosporidium presence and potential source inputs. Sampling was conducted across 9–12 strategically selected sites along Peters Brook and its contributing tributaries. These sites were chosen to increase spatial resolution, capture potential upstream‑to‑downstream gradients, and isolate areas of interest identified during preliminary assessments. The expanded dataset supports identification of localized source areas, and evaluation of land‑use influences. In addition, continued Storm Sampling will further provide additional improved understanding of how storm‑driven processes contribute to microbial contamination.
Methods
This multi-phased study examines Cryptosporidium in the Raritan River Basin using a sampling strategy that includes baseline and event-driven hydrologic conditions. Both phases followed the same framework, collected during non-storm and storm conditions to identify persistent and runoff-driven contamination. In order to capture the rapidly changing conditions common with storm sampling, trailers were deployed before storm events. These trailers were outfitted with automated sampling equipment that were programed to begin sampling at set flow conditions guaranteeing that samples could be collected at key sampling times.
Grab Sample Collection (Phase 1 & Phase 2)
- Most frequently used during non-storm conditions.
- Helps identify chronic or continuous sources within the watershed.
- Provides consistent spatial comparison across sites and phases.
Autosampler Collection (Phase 1 & Phase 2)
- Targets runoff‑driven conditions, including first‑flush and elevated‑discharge periods.
- Captures episodic contamination linked to rainfall, land‑use activities, overland flow, and resuspension.
- Essential for identifying non‑point sources and hydrologic drivers of microbial pulses.
Together, these sampling regimes ensure that both phases of the investigation assess how hydrologic conditions influence Cryptosporidium transport, variability, and potential source contributions throughout the Raritan River Basin.
The USGS New Jersey Water Science Center is partnering with New Jersey American Water (NJAW) on a project in the Raritan River Basin Study area to investigate the potential sources of Cryptosporidium in the Raritan River Basin.
Cryptosporidium (Crypto) is a protozoan parasite of both domestic and wild animals that has been identified as a pathogen of concern and is considered a leading cause of waterborne disease among humans in the United States. Crypto may be introduced to waterbodies failing or improperly connected septic systems and wastewater infrastructure, agricultural lands, wildlife inputs, and runoff. Potential human health risks have been noted for those using the Raritan River Basin because of pathogen exposure for recreational activities. The Raritan River is also a source for drinking water therefore elevated levels have impacts for water treatment.
The USGS New Jersey Water Science Center is partnering with New Jersey American Water (NJAW) on a project in the Raritan River Basin Study area. The objective of the project is to investigate the occurrence and potential sources of Cryptosporidium from multiple rivers and tributaries to the main steam Raritan River.
Phase 1
Phase 1 of the Raritan River Basin Cryptosporidium investigation focused on establishing the presence, spatial distribution, and variability of Cryptosporidium across six key sites in the basin. Initial findings show that Cryptosporidium was present throughout the system, with concentrations and sources influenced by both spatial and temporal factors. Findings from this phase will support broader efforts by New Jersey American Water (NJAW), the U.S. Environmental Protection Agency, and other partners to identify potential environmental and anthropogenic contributors to microbial contamination within the watershed. The initial findings from Phase 1 were used to identify sampling areas and strategies for Phase 2.
Data and insights from Phase 1 are being compiled into a Scientific Investigations Report (SIR), which will provide comprehensive detail on contamination patterns, temporal trends, and potential upstream source locations. This report will inform management actions and assist their ability to perform targeted remediation of microbial contamination in the Raritan River Basin.
Phase 2
Phase 2 of the project focused on the Peters Brook sub‑basin, where Phase 1 results indicated elevated Cryptosporidium presence and potential source inputs. Sampling was conducted across 9–12 strategically selected sites along Peters Brook and its contributing tributaries. These sites were chosen to increase spatial resolution, capture potential upstream‑to‑downstream gradients, and isolate areas of interest identified during preliminary assessments. The expanded dataset supports identification of localized source areas, and evaluation of land‑use influences. In addition, continued Storm Sampling will further provide additional improved understanding of how storm‑driven processes contribute to microbial contamination.
Methods
This multi-phased study examines Cryptosporidium in the Raritan River Basin using a sampling strategy that includes baseline and event-driven hydrologic conditions. Both phases followed the same framework, collected during non-storm and storm conditions to identify persistent and runoff-driven contamination. In order to capture the rapidly changing conditions common with storm sampling, trailers were deployed before storm events. These trailers were outfitted with automated sampling equipment that were programed to begin sampling at set flow conditions guaranteeing that samples could be collected at key sampling times.
Grab Sample Collection (Phase 1 & Phase 2)
- Most frequently used during non-storm conditions.
- Helps identify chronic or continuous sources within the watershed.
- Provides consistent spatial comparison across sites and phases.
Autosampler Collection (Phase 1 & Phase 2)
- Targets runoff‑driven conditions, including first‑flush and elevated‑discharge periods.
- Captures episodic contamination linked to rainfall, land‑use activities, overland flow, and resuspension.
- Essential for identifying non‑point sources and hydrologic drivers of microbial pulses.
Together, these sampling regimes ensure that both phases of the investigation assess how hydrologic conditions influence Cryptosporidium transport, variability, and potential source contributions throughout the Raritan River Basin.