UMass Amherst CEE 370 - Water Resources and Hydrology I

CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 1CEE 370En i onmental Enginee ingUpdated: 19 October 2010Print versionEnvironmental Engineering PrinciplesLecture #19David Reckhow CEE 370 L#19 1Water Resources & Hydrology I: FundamentalsReading: Davis & Masten, Chapter 7 (7.1)Hydrologic CycleD&M, Fig 6-1David ReckhowCEE 370 L#212 Some Terms Surface runoff, overland flow, direct runoff Interflow Infiltration, percolationCEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 2Beneficial uses of water¾ Home UseDrinking, cooking, bathing, cleaning,¾~200 gal/cap/day¾ Power Plants¾ ~800 gal/cap/day¾ Industry¾~200gal/cap/daybathing, cleaning, waste disposalDavid ReckhowCEE 370 L#213¾~200 gal/cap/day¾ Agriculture¾ ~600 gal/cap/day¾ RecreationSwimming, boating, fishing, etc.Drinking WatersAbout 20% of all community water systems in the US use surface water; the remaining 80% uses groundwater. However, the surface water systems tend to be much larger, so that the population served by surface water sources is about two-thirds of the total.David ReckhowCEE 370 L#214Community water systems serve about 83% of the total US population. Most of these employ some form of treatment to make the water microbiologically and chemically safe.CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 3Global Water Balance Showing global mass fluxesShown earlier in the courseIn 1012m3/yrDavid ReckhowCEE 370 L#215Fig. 5.3 in Masters,Compare with Fig. 6.1 in D&M; Fig. 5-27 in MihelcicLocal Water Balance Change in storage = inputs – outputsShown earlier in the course Where: S = storage P = precipitation rateE=evapotranspiration rateIERPdtdS−−−=David ReckhowCEE 370 L#216E evapotranspiration rate Includes transpiration from plants and direct evaporation from water bodies, soil, etc. R = runoff rate I = infiltration rate (or leachate for a landfill)CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 4Local water balance Annual Water budget for Puerto RicoDavid ReckhowCEE 370 L#217From USGS site: http://pr.water.usgs.gov/public/water_use/water_balance.htmlPuerto Rico (cont.) In this case, the USGS includes coastal aquifers within the “control volume” for the mass balance, so:, Becomes: Where groundwater withdrawals (GWW) and groundwater discharge (GW) are two loss processes from the aquifersIERPdtdS−−−=DWGWGWERPdtdS−−−−=David ReckhowCEE 370 L#218discharge (GWD) are two loss processes from the aquifers And now:yrinyrinyrinyrinyrinyrin114623721 −−−−=CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 5Example 7-1 (start)David ReckhowCEE 370 L#219David ReckhowCEE 370 L#2110CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 6Example 7-1 (conclusion)David ReckhowCEE 370 L#2111Drainage Basins Kankakee River basin above Davis, IND&M, Fig 7-2 Dashed line is the basin “divide” Water that falls on one side eventually flows into theDavid ReckhowCEE 370 L#2112flows into the Kankakee Water that falls on the other side goes outside the basinCEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 7David ReckhowCEE 370 L#2113David ReckhowCEE 370 L#2114CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 8Rational Formula Simplified view of runoff; no time resolutionQ = C٭I ٭Ap; Runoff is some fraction of the total rainfall The fraction is the runoff coefficientR = C٭PRunoff (in)Precipitation (in)Runoff CoefficientDavid ReckhowCEE 370 L#2115()Streamflow (m3/s)Rainfall intensity (cm/hr)Basin Area (km2)()AICQcmmkmmshr∗∗=10011036001226 Hydrologic Soil Group Land Use, Crop, and Management A B C D CULTIVATED, with crop rotations Row Crops, poor management .55 .65 .70 .75 Row Crops, conservation mgmt .50 .55 .65 .70 Small Grains, poor management .35 .40 .45 .50 Small Grains, conservation mgmt .20 .22 .25 .30 Meadow .30 .35 .40 .45 PASTURE, permanent w/moderate grazing .10 .20 .25 .30 WOODS, permanent, mature, no grazing .06 .13 .16 .20 Urban residential 30 percent of area impervious .30 .40 .45 .50 70 percent of area impervious .50 .60 .70 .80 David ReckhowCEE 370 L#2116 Hydrologic Soil Group Descriptions: A -- Well-drained sand and gravel; high permeability. B -- Moderate to well-drained; moderately fine to moderately coarse texture; moderate permeability. C -- Poor to moderately well-drained; moderately fine to fine texture; slow permeability. D -- Poorly drained, clay soils with high swelling potential, permanent high water table, claypan, or shallow soils over nearly impervious layer(s).CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 9CT River: one yearDavid ReckhowCEE 370 L#2117CT River: Multi-year Annual flow patternsDavid ReckhowCEE 370 L#2118CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 10Frio Riverhl EphemeralTexas631 mi2drainage basinDavid ReckhowCEE 370 L#2119East River Dominated by SnowmeltColorado289 mi2drainage areaDavid ReckhowCEE 370 L#2120CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 11Suwanee River Spring RainsGeorgia1260 mi2drainage areaDavid ReckhowCEE 370 L#2121Example 7-2David ReckhowCEE 370 L#2122CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 12David ReckhowCEE 370 L#2123David ReckhowCEE 370 L#2124CEE 370 Lecture #19 10/19/2010Lecture #19 Dave Reckhow 13 To next lectureDavid ReckhowCEE 370