Sacramento Coordinated Water Quality Monitoring Program T.R. Grovhoug and C. Suverkropp Larry Walker Associates, Davis, CA Introduction Coordination with Sacramento River Watershed Program Results of CMP Monitoring Future Direction

Introduction

The Sacramento Coordinated Water Quality Monitoring Program (CMP) is a cooperative voluntary program initiated and implemented by the Sacramento Regional County Sanitation District (SRCSD), the City of Sacramento (City), and the County of Sacramento Water Resources Division (County). These three public agencies are responsible for the management of all municipal wastewater and most stormwater in the Sacramento urban area within Sacramento County. The CMP was established in July 1991 through a Memorandum of Understanding between these entities.

The fundamental purpose of the CMP is to develop high-quality data to aid in the development and implementation of water quality policy and regulations in the Sacramento area.

The Ambient Monitoring Program (Ambient Program) is the primary water quality monitoring element of the CMP. Sampling under the Ambient Program began in December 1992 and continues at present on a monthly basis. Additionally, episodic storm events are sampled in coordination with the Sacramento Stormwater Program.

Five river sites are now monitored under the Ambient Program, three on the Sacramento River (at Veteran's Bridge near Alamar Marina, at Freeport Bridge, and at River Mile 44 downstream of the Sacramento metropolitan area) and two on the American River (at Nimbus Dam and at Discovery Park near the confluence with the Sacramento River; see Figure 8.1). The monitoring sites have been selected to provide water quality data upstream and downstream of the influence of urban inputs from the Sacramento community.

The historic emphasis of the Ambient Program has been on trace metals monitoringtotal recoverable and dissolved metalsusing clean techniques and low detection limits. Other parameters monitored under the Ambient Program include organophosphate pesticides (diazinon, chlorpyrifos), total and fecal coliform bacteria, fecal streptococci, total organic carbon, dissolved organic carbon, pH, temperature, dissolved oxygen, hardness, total suspended solids, and electrical conductivity.

Annual reports have been produced each year of the CMP. The latest (1997) Annual Report for the Sacramento CMP presented the results of Ambient Program monitoring completed through December 1997. The next Annual Report will cover data collected through December 1998 and is scheduled for release in spring 1999.

Coordination with Sacramento River Watershed Program

The Sacramento CMP and the Sacramento River Watershed Program (SRWP) are being coordinated at several levels. The SRWP monitoring program (which started as a complete program in June 1998) has been developed in coordination with a number of ongoing monitoring efforts, including the CMP Ambient Monitoring Program. The CMP sampling team will take samples for analysis by the SRWP at four of the five CMP sampling sites. The analytical results produced by the CMP will be combined with other data collected under the SRWP.

The CMP and SRWP have cooperated in the joint sponsorship of the State of the (Sacramento River) Watershed 1997 conference held in October 1997 in Sacramento. This second annual conference was highlighted by awards given to local organizations which distinguished themselves in watershed stewardship. The CMP is a contributor to the November 1998 State of the (Sacramento) River conference which is being sponsored by the Sacramento River Preservation Trust.

Results of CMP Monitoring

Based on Ambient Program results for the period December 1992 to December 1997, ambient water quality characteristics of the American and Sacramento rivers is summarized as follows:

• With few exceptions, ambient water quality characteristics monitored by the Ambient Program meet applicable regulatory standards in both rivers.
• Although observed mercury concentrations in each river meet regulatory criteria proposed in the August 1997 California Toxics Rule, mercury has been identified as a pollutant of concern due to levels in some species of fish.
• Sacramento River water quality characteristics are significantly influenced by flow volumes, with pollutant concentrations decreasing with decreasing flow. This influence is complex, because flows are influenced by regulated dam releases and precipitation throughout the watershed. The effect of flows on quality is largely consistent with the resuspension and transport of sediment-associated metals and other constituents.
• Water quality of the American River near Sacramento is not greatly influenced by changes in flow.
• Statistically significant differences between upstream and downstream locations were observed for some measured water quality parameters. In all cases these changes were small as a percentage of observed concentrations. With the exception of coliform bacteria levels, the differences had no significant impact on compliance with regulatory standards.

Future Direction

The CMP Steering Committee annually reviews the Program and considers appropriate adjustments. At its August 1998 meeting, the Steering Committee decided to add several trace organic constituents to the Ambient Program. The trace organics to be monitored include diazinon, chlorpyrifos, carbofuran, malathion, methyl parathion, polynuclear aromatic hydrocarbons (PAHs), pentachlorophenol, and 2,4,6-trichlorophenol. The basis for selection of these constituents is listing of upstream waters on the 1998 303(d) impaired waters list, identification as a constituent of concern by the Sacramento Stormwater Program, or identification as a constituent of potential concern by Sacramento Regional County Sanitation District. Specialized laboratories capable of producing data at pre-established low detection levels will be contracted to perform this monitoring.

Public outreach and education efforts will continue at the local level. The CMP monitoring effort will continue to be coordinated closely with the activities of the Sacramento River Watershed Program.