ESRM 426 / SEFS 525 Wildland Hydrology

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Transcript of ESRM 426 / SEFS 525 Wildland Hydrology

ESRM 426 / SEFS 525

Wildland Hydrologyhttp://www.cfr.washington.edu/classes.esrm.426/

Course Objectives

This course is designed to give you a basic understanding of:

• the hydrologic cycle especially in wildland watersheds• management effects on components of the hydrologic cycle•Assignments are designed to give you practical knowledge about

how to do routine hydrologic analyses and design• Students will perform hydrologic measurements in the field and

use their data to understand and interpret the hydrologic cycle.  By the end of the course, students will be able to independently •conduct basic hydrologic research•compute basic watershed water balances•locate hydrological data on the web

Course Outcomes•How to do unit conversions for hydrologic analysis, especially with    respect to depth, area, volume relationships •Methods on filling in missing precipitation data and changing point data to areal data •How to measure interception and throughfall components of the hydrologic cycle •How to measure infiltration rates•Understanding how soil moisture varies in space and time•How to compute soil moisture•Understanding basic ground water principles•Understanding how precipitation, soil moisture, groundwater and stream flow are related •How to measure stream velocity and discharge using different methods•How to compute return periods for hydrologic events and compute risk•How and when to use the Rational Formula and the SCS Curve Number method for computing runoff•Awareness of common errors in hydrologic data collection and how to account for them.

Class organization• Arboretum is our watershed/laboratory• Teams will collect data weekly in the field• Collected data MUST entered to google doc

no later than Friday 4:30pm following the lab• Good data recording skills are critical for good

science• For any data turned in late or in the wrong

format, the entire team will lose 5% on the following homework

Class organization

• Everyone– Thursday field trips to UW Arboretum– Homework due at beginning of class

Thursdays

• SEFS 525 graduate students– Paper reviews due Tuesday at beginning of

class

Weekly Arboretum Measurements

• Precipitation

• Throughfall

• Soil Moisture

• Stream discharge (3 locations)

• Water levels in ponds, piezometers and streams

• Water quality

Field Work Responsibilities for Students

• Transportation

• Good field notes and measurements

• Data review and entering to google.docs

• Helping others when done to facilitate overall project

• Equipment gathering

• Equipment return and clean-up!

Class Homework

• Weekly homeworks are quantitative– Need arithmetic, algebra and some

trigonometry

• Homework must be legible

• Show your work!

• Answers should be highlighted and must have correct units

Homework

• Weekly homeworks will be a combination of problems and lab/field work.

• Sometimes you need to make assumptions– Be sure to state those in your homework

Homework Hints

• Think before you do

• Understand what you are doing

• Don’t focus on getting an answer in a hurry

• Pay close attention to units

• Read the book

Objectives: Weeks 1 and 2

1. Learn what hydrology is

2. Learn why water is important and unique

3. Learn how water is distributed globally and nationally

4. Understand why watersheds are important

5. Identify the components of the hydrologic cycle

6. Identify the various agencies that deal with water

7. Learn how to format homework

8. Learn how to recognize significant digits in calculations

9. Learn how to do unit conversions

10.Learn about precipitation

Watersheds and Hydrology

What’s Water Got to Do with It?

• More water moves through ecosystems than any other material

• The materials that it carries and deposits and the energy that it expends are major drivers in shaping the contour of the land and the habitat availability/suitability for organisms.

• Water’s unique properties are the basis for life

What makes water so unique?

Water is extraordinarily anomalousThis web site lists 63 anomalies http://www.lsbu.ac.uk/water/anmlies.html

Let’s look at some of the better known properties of water

What makes water so unique?

What makes water so unique?

• Universal solvent – dissolves more substances than any other liquid– Polarity

Mickey Mouse

What makes water so unique?

• Water is the only natural substance that is found in all three states -- liquid, solid (ice), and gas (steam) -- at the temperatures normally found on Earth

• Water has a high specific heat index. – Can absorb a lot of heat before it begins to get hot.

• This is why water is valuable to industries and in your car's radiator as a coolant.

• The high specific heat index of water also helps regulate the rate at which air changes temperature, which is why the temperature change between seasons is gradual rather than sudden near the oceans.

What makes water so unique?• Pure liquid water has neutral pH

Coke and Pepsi 2.5

What makes water so unique?

• Very High Surface Tension

• Solid state is less dense than liquid state– Ice floats

In other words, water is sticky and elastic, and tends to clump together in drops rather than spread out in a thin film. Surface tension is responsible for capillary action, which allows water (and its dissolved substances) to move through the roots of plants and through the tiny blood vessels in our bodies.

What is hydrology?

• Study of water– Transport of water through the air, over the

ground surface, through the strata of the earth

• Interested in amount, timing, distribution, form, quality

• Quantitative earth science– Foresters– Geologists– Engineers

Earth’s Water

Hydrologic Cycle is a Closed System

Total Volume: 309,000 Units

One Unit (1) = 4475 Cubic Km

(1070 Cubic Miles)

100 Units = Yearly Evaporation From Oceans

300,000 Units = Present Volume All Oceans

From Ritter at U Wisc Stevens Point adapted from Gabler et al. 1999

Global Hydrologic CycleEvaporation From OceansWind Moves Moisture Laden CloudsMoisture Condenses & FallsPrecipitation

Falls Back Into OceansProduces Streamflow On LandEnters Groundwater On LandRe-enters atmosphere via evapotranspiration

Water Returns To OceansQ = P – ET

Runoff (water unit) = Precipitation unit – evapotranspiration unit

http://www.agu.org/journals/wr/wr1009/2010WR009127/2010WR009127.pdf

Water Distribution(Total Storage)

Geomax, P.C. Dr. Donald R. Reichmuth, President

Water Storage Locations(total volume of 1,385,984 1000km3)

Percent of total

Oceans 96.5

Ice 1.76

Groundwater 1.70

Lakes 0.013

Soil Moisture 0.001

Atmosphere 0.001

Streams and Rivers 0.0002

Biosphere 0.0001

Gleick, P. H., 1996: Water resources. In Encyclopedia of Climate and Weather, ed. by S. H. Schneider, Oxford University Press, New York, vol. 2, pp.817-823. from http://earthobservatory.nasa.gov/Features/Water/

Other ways to think about global water distribution

1 gallonAll water

3/8 cupfreshwater 2 tablespoons

surface water

Water storage bins(note use of depth for volume)

• Atmosphere ~ 25 mm• =total volume of water x % in storage/area of earth’s

surface

• Lithosphere ?

• Biosphere ?

• Hydrosphere– Lakes ?– Rivers ?

Depth = Volume / Area

Who measures water?

Who measures water?

• Federal Government

Who measures water?

• Federal government– Dept. of Energy

• Bonneville Power Administration

– Dept. of State• International Water and Boundary Commission

– Dept of Interior• National Park Service• U.S. Geological Survey• U.S. Bureau of Reclamation• U.S. Fish and Wildlife Service

– Dept. of Agriculture• U.S. Forest Service• Agriculture Research Service• National Resource Conservation Service

Who measures water?

• Federal government– Dept. of Defense

• U.S. Army Corps of Engineers

- Environmental Protection Agency- Tennessee Valley Authority– Dept. of Commerce

• Nat. Oceanic and Atmospheric Administration– National Weather Service– National Climate Data Center– National Marine Fisheries Administration

Who measures water?

• TribesIndividual tribes

Northwest Indian Fisheries Council

Who measures water?

• Federal Government

• Tribes

• State Government

Who measures water?

State Government - WashingtonDept. of Ecology

Dept. of Transportation

Dept. of Fish and Wildlife

Dept. of Natural Resources

State Climatologist

Who measures water?

• Federal Government

• Tribes

• State Government

• Local Governments

• NGOs

• Schools

Who measures water?

• Local Governments– Counties– Cities– Watershed Resource Inventory Areas (WRIAs)

• NGOs– The Nature Conservancy– The River Council– American Rivers– Local Watershed Groups

What does this list imply about water and watersheds?

What does this list imply about water and watershed?

• Many jurisdictions

• Overlapping authority

• Information in disparate locations

• Broad interests in water

• Watershed data– EPA Surf your watershed

http://cfpub.epa.gov/surf/locate/index.cfm

– WA Dept of Ecology Water Resource Inventory Area http://www.ecy.wa.gov/services/gis/maps/wria/wria.htm

• Climate data (national and international)http://www.ncdc.noaa.gov/oa/ncdc.html

– Washington State http://www.wrcc.dri.edu/summary/climsmwa.html

Examples of where to locate national data for watersheds and streams

• Stream data- quantity and quality– USGS Water Resources Data

http://water.usgs.gov/data.html

• Soils data– http://soils.usda.gov/

• Aquatic biologic indicators– http://www.epa.gov/bioindicators/

Examples of where to locate national data for watersheds and streams

Who uses water?

How much and who?

• 12 percent of the world's population uses 85 percent of its water

• Current estimates are 4500 cubic km of withdrawals per year

• Existing, accessible, reliable supply = 4200 cubic km

• With no improvements predicted gap of 2800 cubic km by 2030

www.globalissues.org/article/26/poverty-facts-and-stats www.mckinsey.com/App_Media/Reports/Water/Charting_Our_Water_Future_Full_Report_001.pdf

Where does our water go?

• On a global basis, approximately 70% of all available fresh water is used for agriculture.– Africa: 88%– Europe: 33%– USA: 39%

waterencyclopedia.com

kriyayoga.com

instructables.com

ga.water.usgs.gov

US water withdrawals 2000 http://pubs.usgs.gov/circ/2004/circ1268/htdocs/figure01.html

Public supply 11%

Irrigation 34% (31%)

Aquaculture < 1% (2%)

Mining < 1% (1%)

Domestic supply < 1% (1%)

Livestock < 1%

Industrial 5 % (4%)

Thermo-electric Power 48% (49%)

2005 numbers

US Water Withdrawals (% by category)

49

31

1

4

2

111 1

Thermoelectric powerIrrigationMiningIndustrialAquacultureLivestockPublic supplyDomestic

410 billion gallons per day 2005 http://pubs.usgs.gov/circ/1344/

http://ga.water.usgs.gov/edu/maptotal.html

This map shows total (fresh and saline) ground water withdrawals in the United States in 2000. Total about 84,600 million gallons per day (Mgal/d)

~ 83,400 Mgal/d was fresh water ~ 1,260 Mgal/d was saline water (used almost exclusively for mining)~ 68% of fresh ground-water withdrawals went toward crop irrigation ~ 19% was withdrawn by public supply agencies for delivery to homes and businesses.

This map is from U.S. Geological Survey Circular 1268,

Ground water withdrawals

total (fresh and saline) surface water withdrawals in the United States in 2000. Total about 323,000 million gallons per day (Mgal/d).

~ 262,000 Mgal/d was fresh water ~ 68,200 Mgal/d was saline water (used almost exclusively for mining

purposes). ~52% of fresh surface-water withdrawals was used in the electric power production 31% of fresh surface-water withdrawals went toward crop irrigation

This map is from U.S. Geological Survey Circular 1268

Surface water withdrawals

Consumptive Use

• Consumptive use – That part of water withdrawn that is

evaporated, transpired, incorporated into products or crops, consumed by humans or livestock, or otherwise removed from the immediate water environment. Also referred to as water consumed.

http://water.usgs.gov/watuse/misc/consuse-renewable.html

1995

http://www.epa.gov/water/you/chap1.html

Per capita use (gal/day) of public water 1993

http://www.epa.gov/water/you/chap1.html

http://nationalatlas.gov/articles/water/a_wateruse.html

Water Use

• U.S. Per capita = > 85 gallons per person per day household use– How much do you use?

• Freshwater a major global issue– > 1 billion people without access to clean water

• Goal is to provide at least 50 l per capita per day– Compare 85 gallons to 13.5 gallons

Water Footprint

• Idea introduced in 2002 as a complement to the concept of Ecological Footprint

• Related to the idea of virtual water which accounts for all the water used to produce a commodity or service

• e.g., 140 liters 1 cup of coffee

16,000 liters 1 kg of beef in the

grocery store

Virtual Water (water footprint)

• Indicator of water use that looks at both direct and indirect water use of a consumer or producer.

• Total volume of freshwater that is used to produce the goods and services consumed by the individual or community or produced by the business.

http://www.waterfootprint.org/?page=files/home

70 liters

http://www.waterfootprint.org/?page=files/productgallerycars.uk.msn.com/photos/

1100 liters per pound

7000 liters for 1 pound2700 liters

1800 liters per pound

400,000 to 1 million liters

Virtual water exporters (green) and importers (red)

http://www.rwspc.org/documents/EST_061508feature_zimmerman_globalwaterstress.pdf

National Water Footprints

• The water footprint of China is about 700 cubic meter per year per capita. Only about 7% of the Chinese water footprint falls outside China.

• Japan with a footprint of 1150 cubic meter per year per capita, has about 65% of its total water footprint outside the borders of the country.

• The USA water footprint is 2500 cubic meter per year per capita.

Homework helpers

Significant figures

• Standard rules for deciding how many decimal places are mathematically meaningful

• Read document on handout section of web page

• Very easy to overestimate numerical accuracy of calculations using excel– Will start taking points off for sloppiness after

a few warnings

Unit conversions

• Critically important skill for this class

• Need to practice and be patient

• Switch between English and S.I. units

• Switch between depths and volumes

• Can use conversion programs but come test time need to be able to understand and do with a calculator

How much wood can a woodchuck chuck in a year?

• Assumptions– Chuck only during daylight– Chuck only 4 hours a day – Chuck only 9 months a year, not in winter– Assume months all have 31 days (being lazy-not normally

acceptable)– Know that can only chuck 0.05 cords of wood per minute

0.05 cords x 60 minutes x 4 hours x 31 days x 9 monthsminute hour day month year

0.05 cords x 60 minutes x 4 hours x 31 days x 9 monthsminute hour day month year

= 3348 cords/year

Watershed A is 15 sq km, in November it rained 300 mm in November and average streamflow was 1 cms

Watershed B is 100 sq km, in November is rained 200 mm and streamflow was 2 cms

Which watershed had a higher runoff to rainfall ratio?

**cubic meter/second, i.e. the total volume that flowed is equivalent to an average discharge of 1 cms

What is the unit depth of flow in millimeters from a 200 acre

watershed over 10 days with a streamflow of 2 cubic feet per

second (cfs)?