Water Resources/Water Quality

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1 Water Resources/Water Quality From where does your drinking water come? How much land should be set aside for aquifer protection? Why should we care about Barton Springs? What are the effects (if any!) of urbanization on our water resource supplies? How would you expect fecal coliform or other water quality parameters to change with urbanization of watersheds? What is the role of government (you will vote for water resources-related issues in your life time) in planning for and executing water resources? In this session, you will get some hands-on experience in monitoring water quality parameters in Waller Creek, an urban watershed on our campus. You will also investigate the results of water quality sampling by Texas Watch for other urbanized watersheds around Austin. If this work really excites you, you will have the opportunity to do some longer-term sampling on Waller Creek for your class portfolio project. Objectives You will get a chance to conduct some real water quality sampling in Waller Creek. By the end of the lab, the student will be able to: Describe a watershed; Draw a map of Town Lake o Locate City of Austin drinking water plant intake; o Locate where urbanized vs. non-urbanized watersheds flow into Town Lake; o Classify percent urbanization of watershed entering Town Lake; Illustrate the process of urbanization on a watershed s water quality o Explore how water quality parameters vary spatially and temporally using data collected by all discussion sections (called a data time series); o Compare water quality data from Waller Creek with long-term time series data from other urban watersheds in the Austin area (Bull Creek, Shoal Creek) to see how parameters vary spatially and temporally with the degree of urbanization of each watershed; Demonstrate how to collect water samples for water quality analysis properly o Evaluate how sample collection procedures influence analysis results; Estimate a growing city of Austin s degree of urbanization from aerial photos (or satellite images) from land use/land cover maps and 2004 National Agriculture Imagery Program data. pg 1 of 11

2 Overview Watersheds and Water Quality: What is a watershed? Background Images of City of Austin watersheds What are water quality data? City of Austin and Texas Watch water quality data How are water quality data collected? Water quality test kits More advanced procedures What is urbanization Air photos and satellite images What is a watershed? Figure #1 Source: pg 2 of 11

3 John Wesley Powell, scientist geographer, put it best when he said that a watershed is: "that area of land, a bounded hydrologic system, within which all living things are inextricably linked by their common water course and where, as humans settled, simple logic demanded that they become part of a community." Watersheds come in all shapes and sizes. They cross county, state, and national boundaries. No matter where you are, you're in a watershed! Watersheds are defined based on scale as the area of land that drains to a common body of water. Notice on figure 1 how each sub basin defines a watershed that drains into the river acting as the drain of the entire basin s watershed. On a smaller scale, gutters act as the drains for the watershed that is your street. In this session, we will examine water quality data and degree of urbanization on 3 watersheds in Austin: Waller Creek, Shoal Creek and Bull Creek. pg 3 of 11

4 What are water quality data? Water quality reports from the City of Austin can be found searching the link at the end of this document. Texas Watch, a cooperative partnership of the Texas Natural Resource Conservation Commission, the U. S. Environmental Protection Agency and Southwest Texas State University, promotes environmental education and organizes and trains a volunteer network of water quality monitors, assessing water quality on a fraction of Texas nearly 200,000 miles of streams and rivers. From the Texas Watch Volunteer Environmental Monitoring Manual: Texas Watch emphasizes communication about the environment, which is based on the premises that water issues are inextricably linked with air, biological, land, and human resource issues, and that the protection of the environment requires the active, positive, cooperative participation of all Texans. Texas Watch is funded by a USEPA Non-point Source Pollution grant under the Federal Clean Water Act. Non-point sources of pollution degrade water quality as rainfall runoff carries contaminants into water courses or as waterborne pollutants enter groundwater via recharge features or percolation through soil. Non-point source contamination of surface water can cause impairment of the beneficial uses of waterbodies. A water body is impaired if it cannot support one or more of its intended uses. More information on water quality assessment can be found through the EPA and the links at the end of this document. Texas Watch water quality monitors record: ph A range of is considered optimal for most organisms. Water running through and over limestones will have an elevated ph (approximately 8.3 in an open system). Water coming out of Austin s treatment plants can reach 10 (see water reports). Temperature While slow seasonal changes in temperature are tolerated by all local species, drastic temperature changes can cause thermal stress and shock to aquatic organisms. Dissolved Oxygen Oxygen is transferred to water through turbulent surface action from the atmosphere and as a byproduct of photosynthesis. DO levels of parts per million (ppm) are generally required for healthy growth and activity of aquatic organisms. A DO level below 3.0 will cause stress to most aquatic life. If DO levels stay at or below ppm for extended times, most fish will not survive. Conductivity Proxy for dissolved solids. Tends to increase through water use. Turbidity Turbidity measures the level of suspended solids in water. Soil particles suspended in water are commonly listed as leading pollutants. Aquatic life may be smothered (covered, in the case of eggs or young, or suffocated by clogged gills), behave erratically, leave protective cover, or fail to reproduce. High turbidity can also be caused by algal blooms. Decomposition of high levels of algae may cause a reduction in DO. Either cause will block light needed by submerged vegetation. Fecal coliform This is an absence/presence MCL for drinking water standards. It also serves as an indicator of urbanization in streams as a major source in urban waterways is from pet waste. Color Odor Site observations of color, odor, trash count, vegetation abundance, et cetera, can be of utmost importance in identifying changes in conditions at a monitoring site. pg 4 of 11

5 The City of Austin analyzes for: Ammonia as N Conductivity Dissolved oxygen E coli bacteria Fecal coliform bacteria Nitrate/Nitrite as N Nitrate as N Orthophosphate as P ph Sulfate Total dissolved solids (only one record) Total suspended solids Turbidity Temperature (water) and a number of trace elements During you discussion section today, you will collect data on the state-wide standard surface water quality parameters established by Texas Watch. Our goal for the week is to evaluate the spatial and temporal changes that may occur in these parameters, and in so doing, develop an understanding of the possible effects of non-point source pollution on local habitats. How are water quality data collected? Water Quality Test kits There are a number of ways to collect water data. Texas Watch collects baseline water quality data through the use of volunteer monitors trained to use the kit pictured above to measure the parameters that we will this session on Waller Creek. If you are inspired by this week s exercise, you may want to continue monitoring Waller Creek or some other waterbody as part of your portfolio project. Water quality monitors are trained not only to correctly apply the procedures pg 5 of 11

6 to physically measure the parameters, they are also trained to collect data in a way that does not affect the data themselves or data collection efforts downstream. How might samples be contaminated or otherwise improperly collected? Collecting water downstream from where you stand in the waterbody changes not only the flow conditions, but entrains sediment into your sampled water column. Pouring rinse water from your collection container back into the waterbody where you are collecting can cause these same effects. Collecting from a standard depth helps to ensure data are correlatable. Sampling a waterbody from the same spot but from different depths adds a variable to the data that will not be separable from the water quality parameter values. Wearing gloves during sampling protects hands from the reagents that may be used in some tests (none in this session), but also keeps the water in a natural state; suntan lotion, bug spray, perfume, etc. can skew test results. The list can go on indefinitely. What other actions or variations in procedure can you think of that could cause inaccurate data from a single sampling event or a long term data collection project involving multiple sampling events? What is urbanization? Urbanization, the covering of natural land surfaces with impervious pavements, affects streams in a number of ways. Runoff from these paved surfaces quickly carries anthropogenic contaminants to the waterways. Focused runoff and straightened channels increase water velocity, thereby increasing erosion downstream (and turbidity?). Impervious cover retards recharge of groundwater. Urban karst, increased permeability of the fill around utility pipes, conduits etc. compared to surrounding natural subsurface, channels shallow groundwater. Leaking pipes contribute waters of differing chemistries to the natural hydrologic system. The list goes on, and while not all of these affects may be directly harmful to the local environment, certain combinations can significantly degrade water quality. Following are a series of maps of the Austin watersheds we are evaluating in this discussion session. They illustrate land use and land cover for 1983, 1991, 1997, and pg 6 of 11

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11 Important Links & Information from Discussion Section Lecture #5: U.S. Environmental Protection Agency (U.S. EPA) Water Quality Assessment Watershed Homepage Watershed Information Network (answers to frequently asked watershed questions) U.S. EPA Source Water Protection Program (a program to protect quality of drinking water supplies) California's Drinking Water Source Assessment and Protection (DWSAP) Program One state s example of the U.S. EPA s Source Water Protection Program U.S. Geological Survey Water Resources of the United States Clearing house for data related to all things water City of Austin Watershed Protection Development Review Department Texas Watch Non-profit organization comprised of volunteers that collect water quality data of streams and lakes throughout Texas. NOTE: Data collected by you in this discussion section will be made available to the City of Austin and Texas Watch for their water quality monitoring efforts. If you would like to continue monitoring Waller Creek for a Portfolio Project, talk to your TA. pg 11 of 11