regulatory

December 12, 2005

Results of this investigation revealed that trout in the Truckee River are being exposed to significant levels of polycyclic aromatic hydrocarbons (PAHs) within the urban area of Reno and Sparks. Trout downstream of the urban area of Reno and Sparks also have elevated concentrations of arsenic, mercury, and selenium. Based upon these results, the Service is working in conjunction with the cities of Reno and Sparks to develop and implement strategies to reduce non-point source (NPS) pollution to the Truckee River. The Service is also working directly with the Truckee Meadows Water Reclamation Facility to reduce potential impacts from their point source (PS) discharge to the Truckee River. Working with the Cities of Reno and Sparks, along with Washoe County, Pyramid Lake Paiute Tribe, U.S. Geological Survey, Desert Research Institute, University of Nevada- Reno, and the Nevada Department of Wildlife, the Total Maximum Daily Loads (TMDL) standards for several constituents are being assessed and will be revised. The City of Reno also recently issued new storm-water engineering guidelines and best management practices to reduce non-point source pollution to the Truckee River. In addition, approximately 8 acres of riparian habitat were improved on McCarran Ranch to help reduce point and non-point source pollution in the lower Truckee River. Further restoration of the McCarran Ranch is planned along with planned additions of riparian and wetland habitats in the floodplain throughout the Truckee Meadows area for purposes of improving flood control.

Prepared For

U.S. Fish & Wildlife Service
Nevada State Office, Reno, Nevada 89502 (March 6, 2004)

Summary

The factors controlling nitrogen availability, and hence algal productivity, in Pyramid Lake differ from those in the Truckee River, and therefore, an assessment of the impacts of water management strategies must reflect those differences. As a lake, algal production in Pyramid is affected by total available nitrogen from external sources, internal sources, and the nitrogen concentration of lake waters. This dependence of production on a variety of nitrogen sources means that nitrogen availability for a given year depends on the supply of nitrogen to the lake over several years rather than simply during the current year. The Davis Limnology Group developed in 1994 a computer simulation modeling tool that predicts the eutrophication response of Pyramid Lake as a whole to nitrogen loadings. In the past, the U.C. Davis Tool was used to evaluate how different Truckee River Operating Agreement (TROA) alternatives may affect the coldwater fishery of Pyramid Lake for the report to the negotiators (1995) and the DEIS/EIR (1996) compared with current conditions and the No Action Alternative. This study evaluates the TROA alternative developed for the TROA EIS/EIR and compares predictions with current conditions, the No Action Alternative, and a Local Water Supply Alternative (LWS).

Simulated water quality for the lake under current conditions are similar to conditions reported during the 1970's and 1980's. Mean lake concentrations for dissolved inorganic (DIN) and dissolved organic (DON) nitrogen during the final 87 years of the simulation were 0.091 and 0.69 mg/l, respectively, while average algal production was 173 g C/m2?yr. Spikes in the simulated values for the DIN concentration in the lake and annual algal production were associated with years of high river inflow.

The impact of the Alternatives on food availability and habitat for the coldwater fish population of Pyramid Lake was evaluated by comparing values for No Action with values determined for current conditions and by comparing the TROA and LWS Alternatives with the No Action Alternative. Conditions for the No Action Alternative were similar to current conditions, with lower river inflow and corresponding coldwater fishery habitat. Under the TROA Alternative, Truckee River inflow to Pyramid Lake increased by 11,500 acre?ft/yr causing mean lake level for 1913-1999 to be 3.2 ft higher than under the No Action Alternative. This increase in river inflow for the TROA Alternative corresponded with higher predicted DIN loading (3.9 Mg N/yr) and DON loading (13.1 Mg N/yr). Differences in lake characteristics for TROA and the No Action Alternative were relatively small but generally benefited the coldwater fishery of Pyramid Lake. The LWS Alternative provided results similar to the No Action Alternative.

This draft of the Truckee River Operating Agreement (TROA) is the preferred alternative for analysis in the Draft Environmental Impact Statement/Environmental Impact Report to which it is an appendix. This Draft TROA is the result of negotiations among representatives of the United States Departments of the Interior and Justice, the State of California, the State of Nevada, the Pyramid Lake Paiute Tribe of Indians, Sierra Pacific Power Company, and other entities in the State of California and the State of Nevada. This Draft TROA represents agreement among its negotiators that it is a draft and it constitutes the preferred alternative for operating Truckee River Reservoirs in a manner which will carry out terms of Public Law No. 101-618, the Truckee-Carson-Pyramid Lake Water Rights Settlement Act (Settlement Act). Section 205(a)(9) of the Settlement Act requires that the Secretary of the United States Department of the Interior satisfy the requirements of the National Environmental Policy Act in negotiating TROA. Although not a requirement of the Settlement Act, the State of California must comply with the requirements of the California Environmental Quality Act (CEQA).

Section 303(d) of the Clean Water Act requires states to identify waters that do not or are not expected to meet applicable water quality standards with technology-based controls alone. Once these waters are identified, states are to develop total maximum daily loads (TMDLs) at a level necessary to achieve the applicable water quality standards. The Truckee River at Lockwood is listed on Nevada's 303(d) List for total nitrogen, total phosphorus and total dissolved solids. NDEP has chosen to use the chemical specific approach for the establishing TMDLs.

Section 303(d) of the Clean Water Act requires states implement water quality-based controls where technology based limits and implemented Best Management Practices (BMPs) are not sufficient to achieve water quality standards. A TMDL is a tool for implementing State water quality standards and is based on the relationship between pollutant sources and in-stream water quality conditions. TMDLs integrate the management of both point and nonpoint sources of pollution to a waterbody. The TMDL establishes the allowable loadings or other quantifiable parameters for a waterbody and thereby provides the basis for establishing water quality-based controls. These controls should provide the pollution reduction necessary for a waterbody to meet water quality standards.

A TMDL quantifies pollutant sources and allocates allowable loads to the contributing point and nonpoint sources so that the water quality standards are attained. The greatest amount of loading that a water can receive without violating water quality standards is the loading capacity. The waste load allocation (WLA) is the portion of a receiving water's loading capacity that is allocated to existing or future point sources of pollution. EPA regulations (40 CFR 130.2(g)) provide that load allocations for nonpoint sources and/or natural background "are best estimates of the loading which may range from reasonably accurate estimates to gross allotments...."

This document first describes the methodology used for determining a TMDL for both conservative and nonconservative parameters. Then water quality attainment programs other than waste load allocations in the Truckee Meadows Water Reclamation Facility (formerly known as the Reno/Sparks Wastewater Treatment Facility) NPDES permit are discussed. Finally, TMDLs/WLAs for TDS, TN and TP are discussed including a discussion of the proposed NPDES permit and attainability.

The major streams in Nevada have had TMDLs (Total Maximum Daily Loads) established for several years. However for some of these streams, the TMDLs are expressed as an average daily load based upon average long term flow conditions. These TMDLs have been dubbed as "bare bones" TMDLs due to the simplicity of the calculation and their lack of usefulness. While these TMDLs seem to satisfy the requirements of the Clean Water Act, they have contributed little to any watershed/waterbody assessment and restoration plans. These types of TMDLs do little to characterize the problems the TMDLs are intended to address. Without adequate characterizations, appropriate solutions cannot be identified and implemented.