Rainfall, Streamflow, and Water-Quality Data During Stormwater Monitoring, Halawa Stream Drainage Basin, Oahu, Hawaii, July 1, 2003 to June 30, 2004

Abstract

Storm runoff water-quality samples were collected as part of the State of Hawaii Department of Transportation Stormwater Monitoring Program. This program is designed to assess the effects of highway runoff and urban runoff on Halawa Stream. For this program, rainfall data were collected at two sites, continuous streamflow data at three sites, and waterquality data at five sites, which include the three streamflow sites. This report summarizes rainfall, streamflow, and waterquality data collected between July 1, 2003 and June 30, 2004. A total of 30 samples was collected over four storms during July 1, 2003 to June 30, 2004. In general, an attempt was made to collect grab samples nearly simultaneously at all five sites, and flow-weighted time-composite samples were collected at the three sites equipped with automatic samplers. However, all four storms were partially sampled because either not all stations were sampled or only grab samples were collected. Samples were analyzed for total suspended solids, total dissolved solids, nutrients, chemical oxygen demand, and selected trace metals (cadmium, copper, lead, and zinc). Grab samples were additionally analyzed for oil and grease, total petroleum hydrocarbons, fecal coliform, and biological oxygen demand. Quality-assurance/quality-control samples, collected during storms and during routine maintenance, were also collected to verify analytical procedures and check the effectiveness of equipment-cleaning procedures.

Assessing the Feasibility of Soil Infiltration Trenches for Highway Runoff Control on the Island of Oahu, Hawaii

“…This 16 mile (25 km) long freeway was built through some of the most pristine rainforests on Oahu. Limited water quality monitoring data for storm runoff from the construction and operation of H3 on Oahu are available [20][21][22][23][24]. The Clean Water Branch of the Hawaii Department of Health (HDOH) is trying to develop and implement total maximum daily loads (TMDL) for various streams on Oahu, but lacks sufficient data.…”

Effects of the H-3 Highway stormwater runoff on the water quality of Halawa Stream, Oahu, Hawaii, November 1998 to August 2004

“…During 2001 to 2004, data were collected as part of a National Pollutant Discharge Elimination System (NPDES) for the HDOT Storm Water Monitoring Program (State of Hawaii Department of Transportation, 2000). Data from the Storm Water Monitoring Program have been published in annual reports (Presley, , 2002Ball, 2003, 2004); these data are used in this report to evaluate how the highway storm-drain runoff affects Halawa Stream ( fig. 1) and the factors that might be controlling the water quality in the drainage basin.…”