Grantee Research Project Results
2006 Progress Report: Regionally-Based Clean Water Activities I: Modeling and Assessment of Thermal Loading In Support of a Temperature TMDL in the Carson River Basin, Western Nevada
EPA Grant Number: R831600Center: Health Effects Institute (2005 — 2010)
Center Director: Greenbaum, Daniel S.
Title: Regionally-Based Clean Water Activities I: Modeling and Assessment of Thermal Loading In Support of a Temperature TMDL in the Carson River Basin, Western Nevada
Investigators: McKay, Alan , McGwire, Ken
Current Investigators: McKay, Alan , McGwire, Kenneth
Institution: Desert Research Institute
EPA Project Officer: Packard, Benjamin H
Project Period: February 15, 2004 through February 14, 2006
Project Period Covered by this Report: February 15, 2005 through February 14, 2006
Project Amount: $217,998
RFA: Targeted Research Center (2006) Recipients Lists
Research Category: Targeted Research
Objective:
A stream temperature model is being developed and parameterized using geospatial datasets and field data for a selected portion of the Carson River where exceedances of temperature are a concern with respect to its classification as a cold -water fishery. HEATSOURCE. an existing stream temperature model, has been customized for this project to test whether hypothesized re-vegetation strategies along the river could be expected to result in measurable reductions in river temperature. HEATSOURCE will be calibrated using a combination of data sources including LIDAR, color orthophotography, and hyperspectral imagery integrated with field measurements including discharge, water temperature, stream bed temperature, groundwater temperature, wind speed, relative humidity, air temperature and solar radiation. Additionally, a Thermal Infrared Radiometer (T IR) survey was flown over the study area in 2006, which will be used to validate the performance of HEATSOURCE, locate areas of highest thermal loading, and identify zones of groundwater recharge. After calibration and testing, HEATSOURCE will be run using various re-vegetation scenarios in the riparian zone. Results of the model runs with included re-vegetation scenarios will provide valuable information to decision makers that could be used to evaluate the expected effectiveness of such stream restoration plans in satisfying temperature objectives.
The objectives of this project are to:
1. Use remote sensing and geospatial datasets to develop a physically-based characterization of a selected portion of the Carson River that will form the basis for physical temperature modeling;
2. Refine and calibrate the HEATSOURCE temperature model for the study area using image, geospatial and field measured datasets; and
3. Evaluate the expected impact of potential restoration scenarios by simulating a number of revegetation strategies in the temperature model.
Progress Summary:
Thermal loading and re-vegetation strategies are being modeled using the HEATSOURCE temperature model, a one-dimensional. physically based deterministic model developed by the Oregon Department of Environmental Quality (ODEQ).
HEATSOURCE is comprised of modules that simulate open channel hydraulics, flow routing, heat transfer, effective shade, and stream temperature (Boyd et al. 2(04). Many of the inputs to HEATSOURCE are being developed from a 2004 L1DAR-Hyperspectral survey of the Carson River flood plain. HEATSOURCE (and its complementary software called T-Tools) can estimate stream channel morphology from digital elevation data and vegetation maps. However, the morphology routines used by HEATSOURCE for hydraulic modeling are overly simplistic for accurate representation of the low-flow conditions that arc of greatest interest for this study. HEATSOURCE characterizes channel geometry as a single, simple trapezoid with side slopes being determined from manually-de fined bank locations. This approach has two shortcomings. First, the cross-sectional area defined by this manual technique is imprecise and will provide biased estimates for channels that have a convex or concave profile. We have developed a computer program that automatically extracts the most precise and unbiased representation of the channel cross-section from the LIDAR data. The second serious limitation with channel morphology in the original HEATSOURCE code is that the single trapezoid docs not capture the low flow channel within the disturbance zone. Given the availability of coincident high-resolution LIDAR and image data, we have developed a forensic reconstruction of the low-flow channel at the time of the LIDAR data collection in 2004. This effort involved an intensive GPS survey of water depths during a river float at low-flow conditions, adjustment of surveyed river depths for differences in discharge between the time of image acquisition and the field survey using the Manning equation, followed by statistical reconstruction of the wetted cross-sectional geometry of the low-flow channel based on brightness of the image data. Using our LIDAR/image based channel reconstruction we have re-written HEATSOURCE to include the estimated low flow channel within the stream disturbance zone. The hydraulic component of HEATSOURCE is currently undergoing final calibration. These two improvements to the data processing and modeling method for channel geometry arc expected to greatly increase the accuracy of the temperature model. This will in turn allow more realistic specification of whether restoration activities could help stakeholders meet the temperature criteria for the stated beneficial usage of the river.
HEATSOURCE has a solar shade subroutine that accounts for both topographic shading and riparian shading. The radiation reaching the water surface is controlled in the modeling framework by coarse scale topographic shading, fine scale topographic shading, and riparian shading. In order to incorporate the detailed patterns of shading on the river and its banks, land cover attributes of the canopy height, density, and distribution of riparian vegetation are required. We have derived canopy heights from the 2004 LIDAR survey for the HEATSOURCE model. The shading routines in HEATSOURCE were developed for rivers in Oregon where vegetation characteristics were different from the Carson River. Field spectral measurements of shortwave radiation penetrating the canopy were collected in 2005 for the dominant shade trees over a range of canopy densities. Field measures of upwelling and downwelling shortwave radiation have also been made in order to reduce uncertainties in the estimation of light absorption by water given the suspended and dissolved components that affect the clarity of the Carson River. These efforts to accurately estimate the incoming and outgoing shortwave radiation will greatly reduce uncertainty in the energy balance for the river. This work provides information that will be useful for extension to similar watersheds in the intermountain west.
A large number of field observations were made through the 2005 field season for model development and calibration (see Table I), and a select number of these are being repeated in 2006 for validation. In spite of some failure, loss, and vandalization of field equipment, data available for calibration extend from 7/23/05 through 10/6/05 yielding a reasonable calibration period to run HEATSOURCE for the period experiencing temperature exceedances. Preliminary examinations of water temperature measurements from the summer of 2005 sampling period show temperatures at sampling locations are well above the 20°C thermal limit for trout species specified by Nevada Department of Environmental Protection documents. For example, water temperatures at the Lippencott Ski Ranch site were nearly 30°C for three consecutive days (Site 11 in Table I). In addition, diurnal temperature fluctuations in excess of 12°C were observed. Data loss is being minimized in the 2006 validation work by increasing redundancy at the selected field sites. In 2006 we have also arranged to collect a thermal infrared image survey of the Carson River with funds from a different project, and this will prove quite useful to supplement the validation of our model. The high density of field measurements in this study will help to ensure the proper model calibration and increase the confidence in estimates of change associated with simulated revegetation strategies.
Site | Location | Station Type | Flow/Divert | Water temp | Bed Temp | Air T/RH | SW rad | Wind speed | |
---|---|---|---|---|---|---|---|---|---|
1 | GenoaGage | 1 | Flow | ||||||
2 | Genoa Met Station | 2,3 | X | X | X | X | X | ||
3 | Golf course irrigation | 1 | Divert | ||||||
4 | Genoa Golf Course | 2 | X | X | X | ||||
5 | Charney irrigation #1 | 1 | Divert | ||||||
6 | Semick irrigation #1 | 1 | Divert | ||||||
7 | Semick irriga tion #2 | 1 | Divert | ||||||
8 | Last Low Head Dam | 2 | X | X | X | ||||
10 | Rating Curve Site | 1 | Flow | ||||||
11 | Lippincott Ski Ranch | 2,3 | Flow | X | X | X | X | X | |
12 | Ambrosetti Creek Inlet | 1 | Flow | X | |||||
13 | Cradlebaugh Bridge | 1 | X | ||||||
14 | Sun Ridge Golf Course | 2 | X | X | X | ||||
15 | VNT-on Prison Land | 2,3 | X | X | X | X | X | ||
16 | McTamahan | 2 | X | X | X | ||||
17 | Foerscbler Ranch | 2, 3 | X | X | X | X | X | ||
18 | Carson City Gage | 1, 2 | Flow | ||||||
19 | Mexican Dam | 1 | Divert | X | X | X | |||
20 | Riverview Park | 2, 3 | X | X | X | X | X | ||
21 | Empire GolfCourse | 2, 3 | X | X | X | X | X | ||
22 | Morgan Mill Road | 2 | X | X | X | ||||
23 | Deer Run Road Gage | 1, 2 | Flow | X | X | X |
Future Activities:
At this time we are requesting a no-cost extension of the project in order to deal with a delay in start date associated with getting a new graduate student on-board and also to provide enhanced opportunities for outreach to the stakeholder community regarding the nature and significance of our findings. We arc currently working on calibrating the empirical relationships in the model in order to properly estimate the energy balance. The Master' s student who is working on this project, Chris Gamer, is on track for completion of his degree at the end of the Fall 2006 semester.
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.