POTENTIAL EFFECTS OF DEVELOPMENT ON FLOW CHARACTERISTICS OF TWO NEW JERSEY STREAMS¹

Abstract

Parts of the Raritan River basin in central New Jersey have undergone increasing development over the last several decades. The increasing population relies on the region's ground water and surface water sources for its residential, commercial, and industrial water supply. Urbanization, regionalized wastewatertreatment facilities, stream channel alterations, and interbasin transfers of water can all affect water availability. This pilot study was conducted to determine whether significant trends exist in the base-flow and overland-runoff characteristics of streams in two subbasins with different percentages of urban/built-up land (Anderson et at., 1976). Changes in flow characteristics that could indicate future reductions in safe water yield of the Raritan River basin were examined. Flow and flow variability of the steams draining these two subbasins have increased over time. Many of the flow measures studied experienced pronounced trend shifts about 1960. The cause of these changes cannot be readily determined from the data, nor is it clear whether the increased flow variability lies outside the natural range of flow variability of the streams draining the subbasins. (KEY TERMS: land use; trend analysis; time series; LOWESS smoothing.)

Urbanization Affects Stream Ecosystem Function by Altering Hydrology, Chemistry, and Biotic Richness

“…Streams with moderate %TIA had the highest levels of discharge and highest rates of litter breakdown. Unlike streams in other urbanized areas elsewhere in North America (), it appears that urbanization in the lower St. Johns catchment may result in an increase in base flow (Klein 1979, Barringer et al 1994). In our experience, small streams in Northeast Florida with natural land‐cover are intermittent, while similar‐sized streams in urbanized areas are perennial.…”

The effect of climate and land use change on flow duration in the Maryland Piedmont region

“…Their model projected a 2% decrease, and a 7% increase in annual streamflow for the CCC and Hadley predictions, respectively. Urbanization has been observed to lead to enhanced peak flows and reduced base flows by Leopold (1968), Klein (1979), Barringer et al (1994), and Paul and Meyer (2001). Paul and Meyer (2001) also found that urbanizing watersheds exhibit a larger volume of the received precipitation as surface runoff and less as groundwater flow.…”

Untangling the effects of urban development on subsurface storage in Baltimore

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