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LRHO Current Projects
Groundwater Quality vs. Landscape Characteristics
 Previous research has shown that landscape characteristics such as population density and land use can influence surface water quality. Activities on the land surface can also impact groundwater quality and we will examine this linkage by comparing groundwater quality in fifteen sub-basins of the Lamprey River watershed to various landscape characteristics. Groundwater has been collected from homeowner wells in each of the fifteen sub-basins (187 wells total) and will be analyzed for pH, conductivity, dissolved oxygen, nitrate (NO3-), ammonium (NH4+), dissolved organic nitrogen (DON), dissolved organic carbon (DOC), phosphate (PO4-3), arsenic ( As), Uranium (U) and lead (Pb). Results to date show that mean sub-basin nitrate concentration is positively correlated to sub-basin population density (r2 0.45, p<0.01). Further sampling and analysis is currently underway.
Buyofsky, L.A. M.S. Candidate, Department of Natural Resources, University of New Hampshire
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Riparian Nitrogen Dynamics
 Most nitrogen applied to the Lamprey River watershed is retained or transformed somewhere along the flow path. Only 10-20% of that which is applied to the landscape actually enters surface waters, but the exact mechanisms of retention or transformation are unknown. One area where a significant amount of nitrogen can be retained or transformed is in the riparian zone. To document nitrogen transformations along flow paths in the Lamprey watershed, we have installed riparian well fields in two first order streams which drain several suburban developments. Groundwater samples will be collected monthly from the well fields and analyzed for nitrate, ammonium, phosphate, DON and DOC and over the next year. We will also develop a flow net for each well field to link groundwater biogeochemistry with groundwater hydrology.
Daley, M.L. Research Technician, University of New Hampshire
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Nitrogen Retention and Transformation in Instream Wetlands
 Wetlands are known sites of denitrification and instream wetlands could be responsible for a significant amount of nitrogen retention occurring in the Lamprey watershed. Several wetlands receiving elevated nitrogen inputs will be examined in the Lamprey watershed to quantify nitrogen retention and transformations. Surface water inputs and outputs from the wetlands will be sampled for approximately one year and analyzed for nitrate, ammonium, phosphate, DON and DOC. Initial site selection is underway.
Flint, S. M.S. Candidate, Department of Natural Resources, University of New Hampshire
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Nutrient Budget for the Lamprey River Watershed and its Sub-basins
 To develop a detailed hydrologic budget for the Lamprey River watershed, we have monitored precipitation inputs and stream water outputs on a weekly basis during 2004. We have 11 precipitation stations throughout the basin. At five stations, only precipitation volume is monitored. At the six other stations, precipitation volume is recorded and samples are analyzed for nitrate, ammonium, phosphate, DON, DOC, major cations, major anions and silica. Stream samples are collected from twelve sub-basins of the Lamprey and also from the main stem at the USGS gauging station in Durham, NH (referred to as Lamprey). Stream samples will be analyzed for nitrate, ammonium, phosphate, DON, DOC and field parameters. The Lamprey site will also be analyzed for major cations, major anions, silica and DIC. Estimates of input from food, feed and fertilizer will be made based on population and land use data. Sample collection and analysis is currently in progress.
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McDowell, W.H., Daley, M.L., and Skokan, R.D. University of New Hampshire
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Stream Chemistry During High Flow Events in the Lamprey River Basin
Storm events can have significant impacts on stream water quality in both urban and forested and the type of impact may differ according to land use. Very little is known about the chemical response to storm events in suburban basins. To help understand hydrologic flowpaths, hydrochemical processes and the importance of high flow events in suburban basins, stream chemistry was characterized in the Lamprey River basin during high flow events in the 2004 water year. Three sampling sites were chosen in the watershed, each having varying drainage area and discharge. Field measurements (pH, conductivity, dissolved oxygen and temperature) and stream samples were collected during each event to mimic the rise and the recession of the flow event hydrograph. Samples will be analyzed for total dissolved nitrogen (TDN), nitrate (NO3-N), ammonium (NH4-N), orthophosphate (PO4-P), dissolved organic nitrogen (DON), dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), total suspended sediment, particulate carbon, particulate nitrogen, silica and major anions and cations.
Proto, P. M.S. Candidate, Department of Earth Science, University of New Hampshire
Affects of a Frost Horizon on Groundwater Recharge in a Stratified Drift Aquifer
 The importance of meteorological conditions on the presence and extent of a frozen soil horizon is widely recognized in the literature (e.g. Flerchinger et al., 1992 and Stahli et al, 1999, Hayashi et al., 2003). In addition, there is an increasing recognition that frozen soil conditions are important factors in understanding hydrologic and biogeochemical processes in northern New England (Groffman et al., 1999; Hardy et al., 2001; and Decker et al., 2003).
Stratified drift materials represent important groundwater storage reservoirs throughout New England river valleys. One important source of recharge to these deposits is the direct infiltration of snowmelt and precipitation. Because the constructional delta deposits of the Burley-Demeritt Farm (UNH property in Lee, NH) are modern topographic highs, the only recharge is due to infiltration making this an ideal location for investigating infiltration recharge.
 We hypothesize that the amount of snow cover will be a dominant factor in determining the presence and vertical extent of a frost zone. The presence and extent of a frost zone will in turn affect the efficiency with which spring snowmelt and precipitation recharge the aquifer. We also hypothesize that the recharge will be sensitive to the timing of the snowmelt relative the ground thaw and spring rain events. By compiling multi-year records of daily soil temperature, soil moisture, groundwater level, air temperature, precipitation, and weekly measurements of snow moisture content, we will be able to quantify the hydrometeorological factors affecting recharge in the stratified drift deposits of Lamprey River Watershed.
Site characterization will include construction of a detail base map (including topography and surficial geology), a suite of surface geophysical measurements to map the depth the bedrock (magnetometer and seismic) and the stratigraphic features (GPR) of the sand-and-gravel deposits.
 Monitoring will include soil temperature, soil moisture, air temperature, precipitation, snow depth and snow density, and water table elevation. We will most likely employ the commonly used technique of time-domain reflectometry (TDR) to monitor soil moisture along two vertical profiles. However, this is an invasive technique that disturbs the soil in the vicinity of the measurements introducing some error (Roth et al., 1997). We will also explore the feasibility of using electrical resistivity as a non-invasive technique for monitoring soil moisture (Zhou et al. 2002, 2003). One potential advantage of using electrical resistivity is that similar studies could be conducted a larger spatial scales.
Understanding the hydrometeorological factors affecting recharge is a critical component in developing best management practices for water resource and land use as well as understanding the potential impact of climate change on the hydrologic conditions in New England. While individual instrumented plots that monitor hydrologic and meteorological conditions are essential to understanding the processes controlling recharge, these plots will not provide sufficient information about integrated flow rates and pathways. Therefore, we will also plan to explore (stable) isotopic methods of tracking individual pulses of water through the system.
Davis, Jacobs, Clennon and Eller. University of New Hampshire
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Hydrologic Conditions along the North River
To improve our understanding of groundwater stores and flowpaths in the Lamprey River watershed we will conduct a detailed analysis of the hydrologic conditions along the North River. The North River originates at North River Pond in Barrington, flows through a significant marine sand deposit in Nottingham, and then through till-covered bedrock in Lee before reaching the Lamprey River near the intersection of US125 and NH155.
We hypothesize that the different hydrogeologic conditions (marine sand and till-covered bedrock) along the North River are significant controls on the groundwater flow rates and groundwater residence time in the sub-basin. We will test this hypothesis initially by monitoring baseflow conditions along the North River during late summer and early fall using a series of three stream gages (Click to see figure) and at least one monitoring well.
Continuous (though not real time) water levels will be obtained using ultrasonic distance sensors (e.g. Sontek) and data loggers (e.g. Hobo) to gage the flow in the North River at bridges on McCrillis and Freeman Hall Roads, Nottingham, NH. (We have obtained verbal permission from the Town of Nottingham to install sensors at these bridge locations.) Rating curves will be constructed based on manual stream gaging for a range of flow conditions at both stations. Groundwater levels will also be monitored in the Nottingham marine sand deposit. We are also working with the NHGS to identify monitoring wells (or locations for new wells).
The North River Study will be supported by and complement other recent and ongoing activities in the area. The most recent maps of the surficial geology in the Epping and Barrington 7.5 Minute Quadrangles (Goldsmith 1990a, 1990b) are in the final stages of being digitized and will provide important high-resolution coverages for the North River Study. The USGS has recently installed a continuous (real-time) gaging station on the North River that will complement our two gaging stations. The hydrologic analysis of the North River will also complement the ongoing water quality research on the North River (Proto and others).
Davis, Jacobs, Clennon, Proto. University of New Hampshire
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Bedrock Aquifer Flowpaths
Delineation of groundwater flowpaths in fractured rock environments is plagued by the difficulties of obtaining sufficient data at an appropriate scale to successfully apply continuum models (e.g. Darcy's Law) that rely on hydraulic head and hydraulic conductivity to predict flow paths and flow rates. Isotopic tracers are well-established tools for studying the movement of water from the surface into groundwater systems. Although first applied several decades ago (e.g., Stueber et al., 1975; Collerson et al., 1988), radiogenic isotopic tracers, such as 87Sr/86Sr, have recently re-emerged as a potentially powerful tool for studying reactive processes during infiltration ( Johnson and DePaolo, 1997a; Maher et al., 2003; Hogan and Blum, 2003), as well as timescales and flow pathways of water movement (e.g., Johnson and DePaolo, 1997b; Johnson et al., 2000). These types of studies are especially useful, when coupled with trace elemental analyses (e.g., Bau et al., 2004), for quantifying these processes and placing constraints on reactions occurring in the groundwater system.
We propose to use radiogenic isotopes (87Sr/86Sr and 143Nd/144Nd) coupled with trace elements to identify flow paths in the Lamprey River watershed. Our study will potentially provide insights into the identification of recharge areas, residence times of groundwater in these areas, and fate of metals in groundwater systems (e.g., Fee et al., 1992). We will conduct a pilot project on waters hosted by the White Mountain Plutonic Series (K9AB and K7C - Click to see figure). We have selected a site where we anticipate there to be isotopic contrast in the bedrock, based on known isotopic compositions of the igneous and metamorphic hosts (Eby et al., 1992). Preliminary results from water samples collected during Spring 2004 confirm the distinct isotopic signatures in the surface waters occurring in the Massabesic Gneiss Complex (Zmz - Click to see figure) and the White Mountain Plutonic Series.
Our study will consist of samples of the aquifer via analyses of waters from both the lakes and nearby wells. We will also perform leaching experiments on the bedrock, soils and sediments in each area so that we may (1) improve our quantitative understanding of the chemical consequences of mineral dissolution reactions occurring during the infiltration process and (2) therefore effectively capture the isotopic and trace element signal that is contributed in this region.
Our initial sampling will include approximately 20 water samples from lakes and wells, 15 'rock' samples including bedrock, alluvium, and lake sediments, and 15 samples from leaching experiments. The samples will be prepared in the Earth Sciences Geochemistry Lab and the isotopic and trace element work will be conducted off site (e.g. WHOI).
Bryce, Davis and Smith. University of New Hampshire
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