Projects > International Projects
International Projects
Although Waterborne is a US-based company, we provide clients around the world with support. Whether we are providing outreach to local communities in Latin America, assistance in developing new regulatory tools in the People's Republic of China, or determining the effects of changing management strategies on pesticide loadings to rivers in Australia, we have the experience and staff to help you. Use the links below to learn about some of our recent international projects.
Agrochemical Risk Assessment Procedures in China
Evaluation of Mitigation Measures in Australia
PRZM Harmonization with the EU FOCUS Models
Rice Exposure Assessment Models for US, EU, and Japan
Pilot Study of Catchment-Scale Modeling in the UK
EU Exposure Modeling of Veterinary Pharmaceuticals
Agrochemical Drift Deposition in European Streams
Training Sessions in Piacenza, Italy
Biofiltration of Rice-Paddy Runoff in India
Agrochemical Risk Assessment Procedures in China
Waterborne Environmental is working with the Nanjing Institute of Environmental Sciences to develop agrochemical risk assessment procedures for the People’s Republic of China. We led a workshop in Nanjing in May 2009 to exchange information on models, scenarios, and risk assessment procedures as they are currently being used in China, Europe, Canada, and the US, and to develop modeling approaches and scenarios specific to China.
Initial model scenarios were developed for surface water and groundwater assessment for cotton and corn crops, and surface water assessment for rice crops. Scenarios were evaluated using the PRZM, RICEWQ, EXAMS, and ADAM models operating within the Pesticide Risk Assessment Exposure Simulation Shell (PRAESS). Additional scenarios will be added over time.
The Nanjing Institute of Environmental Sciences is one of the affiliated institutions of the Ministry of Environmental Protection of the People's Republic of China. The Institute is a key technical provider for policies, legislation, action plans and technical guidelines on biodiversity conservation in China.
Evaluation of Mitigation Measures in Australia
Sugar cane is an important agricultural commodity in Queensland. With agricultural activities putting pressure on natural resources in this region, it is important to evaluate the effects of mitigation measures to reduce off-target concentrations of diuron from sugar cane production in the Pioneer River watershed so that best management practices (BMPs) can be developed.
Waterborne's approach linked two simulation models: PRZM and RIVWQ, and a geographic information system was used to integrate data for model setup. A baseline modeling scenario was established assuming representative management practices, soil parameters, historical weather records and representative environmental-fate properties for diuron.
Results from the baseline scenario indicated that predictions are at the same order of magnitude as monitored diuron concentrations. To determine the impact of changing agricultural practices, a series of sensitivity analyses was conducted to evaluate mitigation measures individually and in combination. Study results were presented to the regulatory community.
PRZM Harmonization with the EU FOCUS Models
The Pesticide Root Zone Model (PRZM) was first released by the US Environmental Protection Agency (USEPA) in 1984 to simulate the vertical movement of pesticides in the unsaturated soil. Since the model’s inception, Waterborne staff have been involved with the development and enhancement of PRZM and developed a European specific version to handle standard scenarios developed by the FOCUS group
. Waterborne recently made significant changes to PRZM's code to improve the model's functionality.
The first set of enhancements were made to improve PRZM's use for watershed modeling. These changes were: a new sub-lateral flow routine to more closely represent tile drainage; the evapotranspiration routine was changed to allow the use of FAO irrigation and drainage paper 56 based technology; and run-on/run-off buffer model utilization.
The second set of enhancements were made to increase PRZM's harmonization with the FOCUS group's PEARL, MACRO, and PELMO models. These improvements included the addition of aged sorption kinetics, user-defined dispersion lengths, and a daily irrigation file.
Rice Exposure Assessment Models for US, EU, and Japan
Five modeling approaches for estimating environmental concentrations associated with the use of agrochemicals on rice were evaluated by Waterborne to better understand how the model predictions compare to one another, and which model best predicts environmental fate in rice paddies. The comparison of EPA Tier 1, MED-RICE, Japanese regulatory spreadsheet “Ecotox2”, EXAMS-Rice, and RICEWQ was made. These approaches are used in the United States, European Union, and Japan.
The evaluation found that RICEWQ is best suited for higher tier risk assessment based on its ability to conduct probabilistic assessments and to simulate multiple pesticide applications, metabolites, and the flooding, overflow, and controlled releases of water associated with rice production.
Pilot Study of Catchment-Scale Modeling in the UK
Accurate predictions of peak agrochemical concentrations in watercourses in England and Wales are needed as input data to a larger project that seeks to identify the most significant catchment pressures using eco-epidemiological techniques. The UK Environmental Agency currently uses CATCHIS to predict catchment-scale concentrations. There is some concern that CATCHIS underestimates the peak agrochemical concentrations, and thus any modeled data generated may underestimate the potential risk to aquatic organisms.
To be confident in the conclusions of the larger study, there needs to be confidence that input data represent realistic worst case information. Therefore, Waterborne undertook a pilot study for three catchments: Waveney, Yare, and Wensum in the East Anglia region of England. The study compared predictions for nine agrochemicals made by two different models (SWAT and PRZM/RIVWQ) to measured data.
Both models predicted concentrations in the same order of magnitude as the observed bi-weekly data. However, both models fail to accurately predict peak concentrations. Lack of spatially refined agrochemical application data was identified as a major concern in the inaccurate concentration predictions.
EU Exposure Modeling of Veterinary Pharmaceuticals
Veterinary medicines are present in treated animal manure that is applied as a soil amendment and may result in adverse environmental effects. The Waterborne study compared the models used in a phased approach to estimating the fate of the pharmaceuticals for an area in the UK. In each phase, the predicted environmental concentrations (PECs) in the soil were computed and compared with the outcome from other phases.
In phase I of the study a spreadsheet model was used; in second phase VetCalc was used, and in the third phase GIS-based environmental parameters were incorporated into the FOCUS/PRZM model.
When the three phases are compared, the PEC for veterinary pharmaceuticals in the soils decreases in each phase. Phase I, being the most conservative, predicts the highest PECs where as the GIS-based refinements, resulted in the lowest PECs for the region. These results indicate that VetCalc provides a more conservative approach to computing PECs for veterinary pharmaceuticals in the environment, but that using GIS results in better representation of local conditions in estimating PECs in the landscape.
Agrochemical Drift Deposition in European Streams
In order to gain insight on the amount of drift deposition by agrochemicals in streams adjacent to agricultural fields in Europe, a context-setting study was performed by Waterborne. Five potential "worst-case scenario" sites were chosen for comparison to other agricultural areas. These sites represented three major crop types: vines, arable crop, and orchards.
Europe-wide spatial data on land cover and surface water were used to estimate the percentage of crop, amount of water, and proximity of crop to water at a 10km grid level. The distribution for the approximately 26,000 resulting grids across Europe was then compared to the distribution for each of the study sites.
These comparisons showed that for each crop, the 90th percentile of the individual sites is equivalent to a greater than 90th percentile (i.e., 98th percentile) in the distribution for Europe. In other words, this methodology indicates that the study areas are more extreme than most sites in Europe.
Training Sessions in Piacenza, Italy
Waterborne staff taught training sessions as part of the TRAINRICE course held at the Catholic University in Piacenza, Italy. The course provides information on rice agronomic practices, EU registration for rice products, and hands-on experience with rice models linked to groundwater and surface water models.
For higher tier modeling, the European Commission Working Group MED-RICE has recommended linking two Waterborne models, Rice Water Quality Model (RICEWQ) and Riverine Water Quality Model (RIVWQ), to predict environmental concentrations in rice paddies and receiving waters. The Waterborne training focused on setting up and linking these models. The attendees came from a number of countries including Greece, United Kingdom, Sweden, Germany, Italy, and Finland.
Biofiltration of Rice-Paddy Runoff in India
Waterborne staff collaborated with a team of students and professors at the GB Pant University of Agriculture and Technology in India. The team worked on the design, optimization, and installation of a biofilter that removes nitrates and other chemicals from rice-paddy runoff.
The team has found biofilters to be very effective at removing nitrate through biodegradation. They provide a habitat for microorganisms along with a carbon food source. Research continues to explore the possibility of using biofilters to remove other agricultural chemicals from runoff.
The inflow, outflow, precipitation, and other data collected at the biofilter are being monitored using solar-powered data loggers with a satellite modem. This enables the data to be viewed via a website anywhere in the world in near real time.
PRZM Projects
Waterborne staff have been involved with the development and enhancement of PRZM from the model’s earliest development. Along with our experience in user interface development, our unparalleled experience with PRZM has led to requests from clients around the world to assist them in developing custom model scenarios and tools. Waterborne has recently developed prototype user interface tools for Colombia, Norway, and China. These tools are still being refined, but future plans include releasing them as fully functional regulatory tools.
