Chapter 14 Water: A Limited Resource
Overview of Chapter 14 Importance of Water Hydrologic Cycle Water Use and Resource Problems Too Much Water Too Little Water Water Problems in US and Canada Global Water Problems Sharing Water Resources Water Management Providing Sustainable Water Supply Water Conservation
Importance of Water Cooking Washing Use large amounts for: Agriculture Manufacturing Mining Energy production Waste disposal Use of freshwater is increasing
Properties of Water Composed of 2 Hydrogen and 1 oxygen Exists as solid, liquid or gas High heat capacity Polar One end has (+) charge, one end has (-) charge Forms Hydrogen bond between 2 water molecules H-bonds define water’s physical properties
Properties of Water Water is never completely pure in nature Content of seawater (left) Many substances water dissolves cause water pollution
Hydrologic Cycle
Distribution of Water Only 2.5% of water on earth is freshwater 2% is in the form of ice! Only ~0.5% of water on earth is available freshwater
Freshwater Terminology Surface water Precipitation that remains on the surface and does not seep into soil Runoff Movement of surface water to lakes, rivers, etc. Watershed (drainage basin) Land area that delivers water into a stream or river system Groundwater Freshwater under the earth’s surface stored in aquifers Aquifer Underground caverns and porous layers of sand, gravel and rock in which groundwater is stored
Freshwater Aquifer
Water Use and Resource Problems Fall into Three Categories Too much water Too little water Poor quality/contamination (discussed in Chapter 22)
Too Much Water Flooding Both natural and human-induced Modern floods are highly destructive because humans: Remove water-absorbing plant cover from soil Construct buildings on floodplains Floodplain Area bordering a river channel that has the potential to flood
Urban vs. Pre-Urban Floodplains
Floodplain Government restrictions on building Levees can fail Rather than rebuild levees adjacent to rivers, experts suggest allowing some flooding of floodplains during floods (next slide)
Left: Traditional levees adjacent to river Right: Suggested levee style, set back from river
Case-In-Point Floods of 1993
Too Little Water Typically found in arid land Problems Drought Overdrawing water for irrigation purposes Aquifer depletion Subsidence Sinkholes
Too Little Water Problems (continued) Saltwater Intrusion
Water Problems In US and Canada US has a plentiful supply of freshwater Many areas have a severe shortages Geographical variations Seasonal variations
Water Problems in US and Canada Water shortages in West and Southwest Water is diverted and transported via aqueducts
Water Problems in US and Canada- Surface Water Mono Lake (Eastern CA) Rivers and streams that once fed this lake are diverted to Los Angeles (275mi away) Becoming highly saline Court ordered water diversion reduction Colorado River Basin Provides water for 27-million people Numerous dams for Hydropower Colorado River no longer reaches ocean
Colorado River bed in Mexico
Water Problems in US and Canada- Groundwater Aquifer Depletion Ogallala Aquifer
Global Water Problems Amount of freshwater on planet CAN meet human needs BUT, it is unevenly distributed and some places lack stable runoff Problems: Climate Change Drinking Water Population Growth Sharing Water Resources Among Countries
Global Water Problems Water and Climate Change Climate change affects the type and distribution of precipitation Potential issues: Reduced snowfall will impact water resources downstream Sea level rise will cause saltwater intrusion into drinking water supplies
Global Water Problems Drinking Water Problems Population Growth Many developing countries have insufficient water to meet drinking and household needs Population Growth Increase in population means an increase in freshwater requirements Limits drinking water available Limits water available for agriculture (food)
Global Water Problems Sharing Water Resources Among Countries Rhine River Basin (right) Countries upstream discharged pollutants into river Countries downstream had to pay to clean the water before they could drink it Aral Sea (next slide) Water diversion for irrigation has caused sea to become too saline
Aral Sea 1967 1997
Global Water Problems Potentially Volatile International Water Situations Jordan River Nile River
Water Management Main Goal: Provide sustainable supply of high-quality water Requires humans to use resource carefully Dams and Reservoirs Water Diversion Projects Desalinization
Dams and Reservoirs Benefits: Disadvantages Ensure year-round supply of water with regulated flow Generate electricity Provide recreational activities Disadvantages Alter the ecosystem Reduce sediment load
Dams and Reservoirs Glen Canyon Dam To rectify situation Regulated flow has changed ecosystem To rectify situation Canyon has been flooded several times Small floods compared to natural floods Still helps rebuild habitat
Dams and Reservoirs Salmon Population in Columbia R. very low due to dams that impede migration Fish ladders help, but are not effective enough
Water Diversion Projects Requires diverting water to areas that are deficient by pumping through a system of aqueducts Much of CA’s receives its water supply from diverted water from Northern CA Controversial and expensive
Desalinization Removal of salt from ocean or brackish water Two methods: Distillation- salt water is evaporated, and water vapor is condensed into freshwater (salt left behind) Reverse Osmosis- involves forcing salt water through a membrane permeable to water, but not salt Very expensive
Water Conservation Reducing Agricultural Water Waste Agriculture is very inefficient with water Microirrigation- irrigation that conserves waster by piping to crops through sealed systems Also called drip or trickle irrigation
Water Conservation Reducing Industrial Water Waste Stricter laws provide incentive to conserve water Recycling water within the plant Water scarcity (in addition to stricter pollution control requirements) will encourage further industrial recycling Potential to conserve water is huge!
Water Conservation Reducing Municipal Water Waste Gray Water Can be used to flush toilets, wash car or water lawn Water saving household fixtures Government incentives
Conserving at Home Install water-saving shower heads and faucets Install low-flush toilets Fix leaky fixtures Purchase high efficiency appliances Modify personal habits Use the dishwasher instead of washing by hand
NRCS Water Resource Information Systems Claudia C. Hoeft, P.E. National Hydraulic Engineer National Program Manager – Snow Survey and Water Supply Forecasting Program Natural Resources Conservation Service Washington, DC claudia.hoeft@wdc.usda.gov
Snow Survey and Water Supply Forecasting Program Mission Program History Data collection Water supply forecasts Climate services New products Future directions Just run through the bullets
Snow Survey and Water Supply Forecasting Program Mission “…to lead a national cooperative program that provides snow, water and climate information. Our products and services help people use, conserve, improve, and sustain our natural resources and environment.” More boilerplate
NRCS Strategic Goals High Quality Productive Soils Clean and Abundant Water Healthy Plant and Animal Communities Clean Air Adequate Energy Supplies Working with Farm and Ranch Lands These goals are part of the NRCS Strategic Plan 2005-2010 Please note that clean and abundant water are a strategic goal.
Population Increases (1990-2000) Population increases from 1990-2000 in % Annual electricity consumption growth rates from 1988 to 1998 (%) Source: California Energy Commission, Electricity Analysis Office Population growth will be one of the major issues of the next 50 years. The West grew rapidly between 1990-2000 Greatest growth in the driest states! NV, AZ There is only so much water available.
Population Projections (2000-2030) Greatest increases expected in the driest states. Source: U.S. Census Bureau NEEDS: FRESH WATER! Western populations expected to grow. Major reservoir construction unlikely. Continued increases in power likely. Need to manage what we have better. Track climate (SNOTEL) and make informed decisions before it is too late!
Snow Survey and Water Supply Forecasting Program 12 western states including Alaska 60 FTE (36 Field, 24 NWCC) 25.5M acres of irrigated agriculture $51.1B in annual market value (Ag. Census, 2002) Run thru the bullets
A Century Of Progress 1906 - Initial snow studies by Dr. Church Lake Tahoe 1906-1909 - Snow survey sampler perfected 1909-1910 - First water supply forecast issued 1930s – Cooperative Snow Survey Program Established (CFR Title 7, part 612) within USDA Bullets
Snow Survey and Water Supply Forecasting Program Customers Sovereign Nations Canada, Mexico, Native American Nations Technology exchange with China, Mongolia, Antarctica, Europe Federal Departments & Agencies Agriculture, Interior, Commerce, Defense, Energy, Bureau of Indian Affairs, Environmental Protection Agency, Bonneville Power Administration, Federal Water Masters State and Local Agencies State and Interstate Organizations involved in: Drought Planning, Water Resources, Emergency Preparedness, Planning & Zoning, Forestry, Lands, Recreation and Tourism. Just whip thru these…
Snow Survey and Water Supply Forecasting Program Customers Non-Governmental Entities Soil and Water Conservation Districts, University Researchers, Natural Resource Management Businesses, Private Citizens, Agricultural and Forestry Industry Cooperators Water Utilities, Irrigation Districts, Limited Resource Farmers, Construction Contractors, Consulting Meteorologists, Hydrologists and Engineers Educators and Schools, Energy and Power Generation Companies, Landscape Architects, Media, Recreational Interests and Transportation Companies. Just whip thru these.
NRCS SNOTEL Network 12 western states 730+ sites 16 million observations (2005) 16.1 million downloads 920 manual snow courses Includes Alaska SNOTEL are red, snow courses blue Started in the middle 1970s, this is the largest permanent high elevation climate network in the U.S. SNOTEL provides at least daily data. A very busy website, well over a million hits/month. 6.4 million downloads since October 1, 2006 Snow courses read once/month, Jan-May
Meteor-burst Technology SNOTEL uses meteor-burst communications technology to collect and communicate data in near-real-time. VHF radio signals are reflected at a steep angle off the ever present band of ionized meteorites existing from about 50 to 75 miles above the earth. Satellites are not involved; NRCS operates and controls the entire system. The system can pick up signals from the most remote locations.
SNOTEL Site Augmented Data Array Snow water content Precipitation Temperature Snow depth Relative humidity Wind speed/direction Solar radiation Soil moisture / temperature SNOTEL sites can transmit data hourly, or as frequently as necessary. These augmented parameters are very important for simulation models and can be used to verify remote observations from satellites.
NWCC Webpage www.wcc.nrcs.usda.gov NWCC homepage Water Supply SNOTEL Snow Course Data Climate GIS Products - new
NWCC Webpage Map-based interface to datasets Special reports available for specific sensors
NWCC Webpage Rapid access to data organized by data time and frequency of observation real-time hourly - historical Site picture where available Sensor history Tables, tab-delimited, year or period of record Graphs
Mt. Rose SNOTEL Data Users can immediately see current year compared to last year. Plots for all years available.
Daily State Map - Colorado Daily maps of SWE, PRCP, TEMP, Snow Depth for all SNOTEL sites.
Soil Climate Analysis Network SCAN (Soil Climate Analysis Network) 118 sites in 39 states Soil-climate monitoring 956K downloads in 2006 Critical for drought monitoring Started in the early 1990s, this network has a Midwest and East focus. One of the very few real-time soil moisture and soil temperature networks in the U.S. The High Plains Regional Climate Center operates one, but only at the 4” depth. NRCS has worked with manufacturers to perfect the technology. Vitel sensors are installed on the network one sensor measures moisture and temperature. For a limited area, provides ground truth for validation of soil moisture models or remote sensing values.
Johnson Farm, Nebraska SCAN Site Typical Midwest installation. Small footprint. Solar powered. Soil moisture/temperature – 2, 4, 8, 20, 40 inch depths Precipitation Temperature Wind speed/direction Relative humidity Solar radiation Snow water equivalent and depth in appropriate regions.
SCAN Data Plot
Water Supply Forecasts Water Year 2006 740 locations forecast Jan-Jun with NWS Over 11,534 forecasts issued by states to users Over 1.9M visits to WSF pages We do this every Jan-Jun in cooperation with the National Weather Service. Each month about 60,000 unique customers download forecasts.
New Products - Viewers Google Earth SNOTEL http://www.wcc.nrcs.usda.gov/snotel/earth/index.html Water Supply Forecasts http://www.wcc.nrcs.usda.gov/wsf/earth/index.html SNOTEL and WSF Each location is color coded to indicate % of average. Rapid navigation to each point, click and site specific information is displayed.
New Products - WSF Significant rain or snow events can happen anytime. Since we only issue official WSF once a month users want to know the effects of a prolonged dry period or heavy rain/snow event are having on WSF between official issue dates. Here we see a significant precipitation/snow event for Wesner Spring, NM the end of December. Rapid changes in snowpack affect water supply forecasts
New Products - WSF Daily water supply forecasts use daily SNOTEL data NWCC has developed a daily WSF process that uses daily precipitation and snowpack information from SNOTEL sites to calibrate a statistical model for every day of the year. The model is run every day and provides trend analysis between the official forecast dates. This image illustrates the impact of the recent event on expected March-July streamflow volumes for the Pecos River at Anton Chico, NM. Exceedance probabilities are shown for 10, 30, 50, 70, 90% Daily water supply forecasts use daily SNOTEL data
New Products – Climate Maps Maps of snowpack, precipitation, temperature Long-term partnership with Oregon State University Mapping of normals and monthly Precipitation Temperature Dewpoint Growing season length Plant Hardiness map These are the benchmark climate maps for the U.S. Oregon State University http://www.ocs.orst.edu/prism/
Future Directions Further automating of manual snow courses to SNOTEL sites where real-time information is needed to provide water supply forecasts. Expansion of SCAN to provide governments, water managers, agricultural producers, businesses and researchers improved information about soil moisture conditions and potential droughts. Improving models and computational capacity to provide more frequent and accurate water supply forecasts and assessments of soil moisture. These goals will all help the research community.
Thank You! Questions?