Multi-year data of water chemistry including nutrient concentrations for various forms of N, P, C, as well as suspended sediments, was determined from monthly grab samples taken at watershed inputs to the Plum Island Sound Estuary. Sampling sites were the Ipswich River (Sylvania Dam, Ipswich, MA), Parker River Dam (Central St, Newbury, MA), Egypt River (Ipswich, MA) Mill River (Newbury, MA), Muddy Run (Ipswich, MA), Little River (Newbury, MA). These nutrient concentrations are then used in conjunction with USGS discharge data (recorded at gages in the Parker River at Byfield, MA and the Ipswich River at Ipswich, MA) to calculate annual nutrient loading to the Plum Island Sound Estuary, coming over each dam. Annual yield is also calculated for both dams. Refer to file WAT-VA-Load for loading data.
Grab samples are collected monthly at the Parker and Ipswich dams, and Egypt River. Samples at Mill River and Muddy Run were taken in 1999. Water is filtered and/or partitioned for analysis for suspended solids, particulate organic nitrogen (PON), total dissolved nitrogen (TDN), ammonium (NH4), nitrate (NO3), dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON), particulate phosphorus (PPO4), total dissolved phosphorus (TDP), phosphate (PO4), particulate organic carbon (POC), dissolved organic carbon (DOC). Occasionally chlorophyll and phaeopigments in addition to stable isotopes of dissolved and particulate forms of nitrogen and carbon are analyzed.
Nutrient samples continue to be taken monthly. Monthly nutrient concentrations are updated annually in WAT-VA-Inputs. Every 2-3 years, WAT-VA-Load is updated with loading calculated from concentrations in WAT-VA-Inputs.
01) 27-Sep-2006 EML metadata created level ~3.5 includes attribute information
02) 13-Aug-2007 updated EML metadata to level 4-5
03) 21-Sep-2007 updated data set to Aug 2007 data.
04) 8-Jan-2010 updated data to Oct 2008 data
Version 05: January 25, 2012, updated data and metadata to Dec 2010. Used MarcrosExportEML_HTML (working)pie_excel2007.xlsm 1/18/12 4:51 PM for QA/QC to EML 2.1.0
Version 06: February 1, 2012, updated data and metadata to Dec 2010. Used MarcrosExportEML_HTML (working)pie_excel2007.xlsm 1/27/12 4:35 PM for QA/QC to EML 2.1.0
Version 07: February 9, 2016, updated data and metadata into 2015 to comply with importation to Drupal and LTER PASTA. Used MarcrosExportEML_HTML (working)pie_excel2007_Jan2015.xlsm 1/15/15 4:26 PM for QA/QC to EML 2.1.0
Version 08: February 25, 2016, update site names, data and metadata updates to comply with importation to Drupal and LTER PASTA. Used MarcrosExportEML_HTML (working)pie_excel2007_Jan2015.xlsm 1/15/15 4:26 PM for QA/QC to EML 2.1.0.
Version 09: September 12, 2019, data and metadata updates to comply with importation to DEIMS7 and LTER Data Portal. Used MarcrosExportEML_HTML (working)pie_excel2007_Sep2019.xlsm 9/3/19 5:19 PM for QA/QC to EML 2.1.0
Version10:February 19, 2022 Updated data and metadata through 2019