Surface Water Monitoring

Streams either gain water from inflow of groundwater from the underlying aquifer or lose water by outflow to the underlying aquifer. Many streams do both, gaining in some reaches and losing in other reaches. Furthermore, the groundwater flow directions near any given stream can change seasonally as the altitude of the water table changes with respect to the stream-surface altitude or when rapid...

Approximately 30% of the world’s water is stored as groundwater. Groundwater moves very slowly, on the order of feet per day, however it is still part of the hydrologic cycle. Most of the water in the ground comes from precipitation that infiltrates downward from the land surface.

As part of the U.S. Geological Survey's (USGS) program for disseminating water data within USGS, to USGS cooperators, and to the general public, the USGS maintains a distributed network of computers and fileservers for the acquisition, processing, review, and long-term storage of water data. This water data is collected at over 1.5 million sites around the country and at some border and...

Surface water current conditions are based on the most recent data from on-site automated recording equipment. Measurements are commonly recorded at a fixed interval of 15 to 60 minutes and transmitted by satallite uplink or telephone telemetry to the USGS every hour. Values may include "Approved" (quality-assured data that may be published) and/or more recent "Provisional" data (of unverified...

Water-level measurements from observation wells are the principal source of information about the hydrologic stresses acting on aquifers and how these stresses affect groundwater recharge, storage, and discharge (Taylor and Alley, 2001). Water-level measurements are made by many Federal, State, and local agencies.

A groundwater system consists of a mass of water flowing through the pores or cracks below the Earth's surface. This mass of water is in constant motion. Water is constantly added to the system by recharge from precipitation, and water is constantly leaving the system as discharge to surface water and as evapotranspiration. Each groundwater system is unique in that the source and amount of water...

The Mohawk River near Schenectady, NY is prone to ice jams during periods of river-ice break-up. Ice jams in this reach typically form at channel constrictions, bridge piers, lock and dam structures, and sections with a reduced floodplain (Foster and others, 2011). Ice jam related flooding can result from backwater associated with the jam or from water released downstream when a jam fails...

Objective: The USGS New York Water Science Center (NYWSC) works with other Federal agencies as well as with State, municipal, and tribal agencies to provide research and data about water-related issues. Relevance and Impact: The NYWSC leads the scientific and water-resources management communities by providing high-quality, timely, and unbiased scientific data, reports, and other information that

The USGS NY Water Science Center maintains a network of near-real-time sensors to monitor the movement of suspended sediment into and through the freshwater reach of the tidal Hudson River. Information from this network helps quantify the movement of sediment in the watershed to assist resource managers and stakeholders reduce dredging costs, target resources to mitigate soil loss, and modify land...

Problem Suspended-sediment concentration (SSC) and turbidity are primary water-quality concerns in New York City’s (NYC) water-supply system (U.S. Environmental Protection Agency, 2007). In the NYC water-supply system turbidity is largely caused by clay and silt rather than organic material (Effler et al. 1998, Peng et al. 2002, 2004). Sediment can originate from the watershed land surface and the

Background The Ashokan Reservoir is located in the Catskill Mountains of New York State and is part of New York City’s (NYC) water supply system. The NYC water-supply system is operated by the NYC Department of Environmental Protection (NYCDEP) under a filtration avoidance determination (FAD) issued by the New York State Department of Health. The Ashokan Reservoir watershed is 255 mi2 and is one o

Background Streams and rivers are an important environmental resource and provide water for many human needs. Streamflow is a measure of the volume of water carried by rivers and streams. Changes in streamflow can directly influence the supply of water available for human consumption, irrigation, generating electricity, and other needs. In addition, many plants and animals depend on streamflow