This dataset includes discrete water quality and discharge data for three streams that flow through wetlands. There are two measurement and sampling locations on each stream: one immediately upstream from the wetland and one immediately downstream from the wetland. Measurements and sample collection occurred in 2010 and 2011 at West Twin Creek, AK; in 2019 and 2020 at Allequash Creek, WI; and in 2013, 2014, and 2017 at the Big Thompson River, CO. The upstream and downstream data from Allequash Creek and the Big Thompson River are from established USGS sites. At Allequash Creek, the downstream site is USGS 05357206 Allequash Creek Site No. 3 Nr Boulder Junction, WI, and the upstream site is USGS 5357205 Allequash Creek Near Sayner, WI. At the Big Thompson River, the downstream site is 402114105350101 Big Thompson Bl Moraine Park Nr Estes Park, CO, and the upstream site is USGS 402123105370401 Big Thompson R Nr Fern Lake Road, RMNP, CO. All measurements were recorded over water years (October 1 - September 30). Some of these data are also available in the National Water Information System by the United States Geological Survey (https://waterdata.usgs.gov/nwis), and are included here for dataset completeness. The data available in NWIS includes discharge at the Allequash Creek downstream gage and the Big Thompson River downstream gage, and specific conductivity at the Allequash Creek downstream gage, the Big Thompson River downstream gage, and the Big Thompson River upstream gage.