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Description of the Hydrologic Cycle 

# Precipitation Temperature

Evaporation



# Streamflow

This 

### is an education module about the movement of water on the planet Earth. The module includes 

### a discussion of water movement in the United States, and it 

### a/so provides specific information about water movement in Oregon. The scientific discipline in the field ofphysical geography that deals with the water cycle 

### is called hydrology It 

### is concerned with the origin, distribution, andproperties of water on the globe. Consequently, the water cycle 

### is a/so called the hydrologic cycle in many scientific textbooks and educational materials. 

### Most people have heard of the science ofmeteorology and many 

### a/so know about the science of oceanography because of the exposure that each discipline 

### has had on television. People watch TV weatherpersonalities nearly evel}f day. Celebrities such 

### as Jacques Cousteau have helped to make oceanography a commonly recognized science. In a broad context, the sciences ofmeteorology and oceanography describe parts ofa 

### series of global physical processes involving water that are 

### a/so major components of the science ofhydrology. Geologists describe anotherpart of the physical processes by addressing groundwater movement within the planet's subterranean features. Hydrologists are interested in obtaining measurable information and knowledge about the water cycle. 

### A/so important 

### is the measurement of the amount of water involved in the transitional stages that occur 

### as the water 

### moves from one 

### process within the cycle to other

### processes. Hydrology, therefore, 

### is a broad science that utilizes information from a wide range of other sciences and integrates them to quantify the movement of water. The fundamental tools ofhydrology are based in supporting scientific techniques that originated in mathematics, physics, engineering , chemistry, geology, and biology. Consequently, hydrology 

### uses developed concepts from the sciences ofmeteorology, climatology, oceanography, geography, geology, glaciology, limnology (lakes), ecology, biology, agronomy, forestry, and other sciences that specialize in otheraspects of the physical, chemical or biological environment. Hydrology, therefore, 

### is one of the interdisciplinal}f sciences that 

### is the 

### basis for water resources development and water resources management. The global water cycle can be described with nine majorphysical 

### processes which form a continuum of water movement. Complex pathways include the passage of water from the gaseous envelope around the planet called the atmosphere, through the bodies of water on the sur.face of earth such 

### as the 

### oceans, glaciers and lakes, and at the 

### same time (or more slowly) passing through the soil and rock layers underground

. Later, the water 

### is returned to the atmosphere. A fundamental characteristic of the hydrologic cycle 

### is that it 

### has no beginning an it 

### has no end. It can 

### be studied by starting at any of the following 

### processes: evaporation, condensation, precipitation, interception, infiltration, percolation, transpiration, r.unoff, and storage. The information presented below 

### is a greatly simplified description of the major contributing physical 

### processes. They include: 

### EVAPORATION

E vaporation occurs when the physical state of water 

### is changed from 

### a liquid state to 

### a gaseous state

. A considerable amount ofheat, about 600 calories ofenergy for each gram of water, 

### is exchanged during the change ofstate. Typically, solar radiation and other factors such 

### as air temperature, vapor pressure, wind, and atmospheric pressure affect the amount ofnatural evaporation that takes place in any geographic area

. Evaporation can occur on raindrops, and on free water 

### sur.faces such 

### as seas and lakes. 

### It can even occur from water settled on vegetation, soil, rocks and snow. There 

### is a/so evaporation caused by human activities. Heated buildings experience evaporation of water settled on its sur.faces. Evaporated moisture 

### is lifted into the atmosphere from the ocean, land sur.faces, and water bodies 

### as water vapor. Some vapor always exists in the atmosphere

. 

### CONDENSATIONCondensation is the process by which water vapor changes it's physical state from 

### a vapor, most commonly, to 

### a liquid. Water vapor condenses onto small airborne particles to form dew, fog, orclouds. The most active particles that form clouds 

### are sea salts, atmospheric ions caused by lightning, and combustion products containing sulfurous and nitrous acids. Condensation is brought about by cooling of the air orby increasing the amount of vapor in the air to its saturation point. When water vapor condenses back into 

### a liquid state, the same large amount ofheat ( 600 calories of energy pergram) that was needed to make it 

### a vapor is released to the environment. 

### PRECIPITATION

Precipitation is the process that occurs when any and all forms of waterparticles fall from the atmosphere and reach the ground

. There are two subprocesses that cause clouds to release precipitation , the coalescence process and the ice-crystal process. As water drops reach 

### a critical size, the drop is exposed to gravity and frictional drag. A falling drop leaves 

### a turbulent wake behind which allows smaller drops to fall faster and to be overtaken tojoin and combine with the lead drop. The othersub-process that can occur is the ice-crystal formation process. 

### It occurs when ice develops in cold clouds or in cloud formations high in the atmosphere where freezing temperatures occur. When nearby water droplets approach the crystals some droplets evaporate and condense on the crystals. The crystals grow to 

### a critical size and drop as snow orice pellets. Sometimes, as the pellets fall through lower elevation air. they melt and change into raindrops. Precipitated water may fall into 

### a waterbody or it may fall onto land

. 

### It is then dispersed several ways. The water can adhere to objects on or near the planet surface orit can 

### be carried overand through the land into stream channels, orit may penetrate into the soil, orit may be intercepted byplants

. When rainfall is small and infrequent, 

### a high percentage ofprecipitation is returned to the atmosphere by evaporation.
The portion of precipitation that appears in surface streams is called runoff. Runoff may consist of component contributions from such sources as surface runoff, subsurface runoff, orground water runoff. Surface runoff travels over the ground surface and through surface channels to leave 

### a catchment 

### area called 

### a drainage basin or watershed. The portion of the surface runoff that flows over the land surface towards the stream channels is called overland flow. The total runoff confined in the stream channels is called the streamflow

. 

### INTERCEPTION

Interception is the process ofinterrupting the movement of water in the chain oftransportation events leading to streams. The interception can take place by vegetal cover or depression storage in puddles and in land formations such as rills and furrows

. When rain first begins, the water striking leaves and other organic materials spreads over the surfaces in 

### a thin layer orit collects at points or edges

. When the maximum surface storage capability on the surface of the material is exceeded, the material stores additional water in growing drops along its edges. Eventually the weight of the drops exceed the surface tension and water falls to the ground. Wind and the impact of rain drops can also release the water from the organic material. The waterlayer on organic surfaces and the drops of water along the edges 

### are also freely exposed to evaporation. Additionally, interception of water on the ground surface during freezing and sub-freezing conditions can be substantial. The interception offalling snow and ice on vegetation also occurs. The highest level ofinterception occurs when it snows on conifer forests and hardwood forests that have not yet lost their leaves. 

### INFILTRATION

Infiltration is the physical process involving movement of water through the boundary area where the atmosphere interfaces with the soil. The surface phenomenon is governed by soil surface conditions. Water transfer is related to the porosity of the soil and the permeability of the soil profile. Typically, the infiltration rate depends on the puddling of the water at the soil surface by the impact ofraindrops, the texture and structure of the soil, the initial soil moisture content , the decreasing water concentration as the water moves deeper into the soil filling of the pores in the soil matrices, changes in the soil composition , and to the swelling of the wetted soils that in tum close cracks in the soil.Water that 

### is infiltrated and 

### stored in the 

### soil can 

### a/so become the water that later 

### is evapotranspired or becomes subsurface runoff. 

### PERCOLATION

Percolation 

### is the movement of water though the 

### soil, and it's layers, by gravity and capillary 

### forces

. The prime moving force ofgroundwater 

### is gravity

. Water that 

### is in the zone of aeration where air

### exists is called vadose water. Water that 

### is in the zone ofsaturation 

### is called groundwater. For all practical purposes, all groundwater originates 

### as surface water. Once underground, the water 

### is moved by gravity. The boundary that 

### separates the vadose and the saturation 

### zones is called the water table. Usually the direction of water movement 

### is changed from downward and 

### a horizontal component to the movement 

### is added that 

### is based on the geologic boundary conditions

. Geologic fonnations in the earth's crust 

### serve as natural subterranean reservoirs for storing water. Others can 

### a/so serve as conduits for the movement of water. Essentially, all groundwater 

### is in motion. Some ofit, however, moves extremely slowly. A geologic fonnation which transmits water from one location to another in sufficient quantity for economic development 

### is called an aquifer. The movement of water 

### is possible because of the voids or

### pores in the geologic fonnations

. Some fonnations conduct water back to the ground surface

. A spring 

### is a place where the water table reaches the ground surface. Stream channels can be in contact with an unconfined aquifer that approach the ground surface. Water may move from the ground into the 

### stream, or visa versa, depending on the relative water level. Groundwater discharges into 

### a stream fonns the 

### base flow of the 

### stream during dry periods, especially during droughts. An influent 

### stream supplies water to an aquifer while and effluent 

### stream receives water from the aquifer. 

### TRANSPIRATION



# ..

. 

# .

Transpiration 

### is the biological 

### process that occurs 

### mostly in the day

. Water inside ofplants 

### is transferred from the plant to the atmosphere 

### as water vapor through numerous individual/eave openings. Plants transpire to move nutrients to the upperportion of the plants and to cool the leaves exposed to the sun

. Leaves undergoing rapid transpiration can be significantly cooler than the sunounding air. Transpiration 

### is greatly affected by the species ofplants that are in the 

### soil and it 

### is strongly affected by the amount oflight to which the plants are exposed. Water can be transpired freely by plants until 

### a water deficit develops in the plant and it water-releasing cells (stomata) begin to close

. Transpiration then continues at 

### a must slower rate

. Only 

### a small portion of the water that plants absorb are retained in the plants. Vegetation generally 

### retards evaporation from the 

### soil. Vegetation that 

### is shading the 

### soil, reduces the wind velocity. 

### Also, releasing water vapor to the atmosphere reduces the amount of direct evaporation from the 

### soil or from snow or ice cover. The absorption of water into plant 

### roots, along with interception that occurs on plant surfaces 

### offsets the general effects that vegetation 

### has in retarding evaporation from the 

### soil

. The 

### forest vegetation tends to have more moisture than the 

### soil beneath the 

### trees. 

### RUNOFF

Runoff 

### is flow from 

### a drainage basin or watershed that appears in surface 

### streams. 

### It generally consists of the flow that 

### is unaffected by artificial diversions, 

### storages or other works that society might have on orin 

### a stream channel

. The flow 

### is made up partly ofprecipitation that falls directly on the 

### stream , surface runoff that flows over the land surface and through channels, subsurface runoff that infiltrates the surface 

### soils and moves laterally towards the 

### stream, and groundwater runoff from deep percolation through the soil horizons

. Part of the subsurface flow enters the 

### stream quickly, while the remaining portion may take 

### a longerperiod before joining the water in the 

### stream

. When each of the component flows enter the 

### stream, they fonn the total runoff

. The total runoff in the 

### stream channels 

### is called streamflow and it 

### is generally regarded 

### as direct runoff or 

### base flow

. 

### STORAGE

There are three basic locations of water storage that occur in the planetary water cycle

. Water 

### is stored in the atmosphere; water 

### is stored on the surface of the earth, and water stored in the ground. Water stored in the atmosphere can be moved relatively quickly from one part of the planet to anotherpart of the planet. The type of storage that occurs

### on 

### the land sudace and 

### under the ground 

### largely

### depend on the geologic fe&tUIIiiS 

### rr:Nated 

## to the types of

### soil and the types of

### rocks present at the stomge locations. 

### storage occurs as surfece 

### storage in oceans, 

### lakes, resetVoirs, and glaciers; 

### underground stotage 

### occurs in the soil, in aquifers, 

### andin the crsvicas of rock fonnations. The 

### movement of 

### water through the eight other

### major physical

### processes of

### the watercycle can 

### be erratic. On 

### average, waterthe atmosphel& is rsnewed evety 16 days. Soil 

### moisture is replaced about everyyear. Globally; 

### waters in wetlands are replaced about evety 

### 5 years while the residence time of 

### lake waterIs about 

### 17

### years. In 8f8BS 

### of

### low development by society. groundwater1811f1Wal can exceed 1, 400 

### yeat8. The 

### uneven distribution and 

### movement of 

### water aver time. and the spatial distribution of 

### waterin both geographic and geologic a/9BS, 

### can cause exf18111e 

### phenomena such as floods 

### and droughts to 

### occur.

ESTIMATED GLOBAL WATER CYCLE
TYPE OF LOCATION VOLU!'IE PERCENT OF TOTAL WATER millions of millions of IIOLU!'IE cu. miles cu kilometer
SALT WATER 97.88

oc:eans 314.2 1388.8 (96.4:10) saline bodies 2.1 8.7 (8.61)
FRESH WATER 2.98
ice 

## a snOIIil 6.9 28.7 (2.1S) lakes e.s 2.1 (8.15:10) rivers 8.81 8.84 (8.883:10)
accessible aroundwater 1.8 4.2 (8.31:10) All'I)SPHERIC 8.18

ua evaporation 8.1 8.42 (8.83:10) lond evaporation e.8s 8.21 (8.815:10) precipitation over sea 8.89 8.37 (8.83:10) pretipitation ovar land 8.83 8.12 (8.81:1:)
water vapor 8.885 8.82 (8.882:10) ROI.INOED TOTAL 326.88 1357.88 188.8



### Ifa ftfty..five gallon drum of 

### waterf9fJ19Senled the total supply of 

### water on the planet then: ll) the 

### oceans would

### be represented 

### by53 gallons, 1 qu.rt, 1 pint and 12 ounces; b) 

### the i_,a Mid 

### glaci81S would ,_., 1 gallon, Mid 

### 12 ounC811; c) the 

### afmosph- would contribute 1 pint

### and4.5 ounces; d) 

### groundMitw would 

### add up 

### to 1 quart 

### •nd 11.4 

### ounces; e) 

### livshwafar leku would,_., 

### one helf

### ounc.;**~** 

### Inland 

### seas andsalina lalru would add 

### up 

### to 

### ovar one fllln1 of 

### an ounce; 

### g) 11011 mol.ture Mid valdotJe 

### wafar 

### would (Otll 

### to eout

### one fourth 

### of•n ounce; h) 

### the rivflnl 

### of file 

### world would only add 

### up 

### to one-hundnJdth of 

### an 

### ounce (less fll•n 

### one OllfHIJillionfll of

### the wafar 

### on file

## pltme#J.
WATER BUDGET IN THE UNITED STATES
The 

### atmosphel& above the 48 coterminous United 

### States of America stores about 36.5 cubic miles 

### per day of

### atmospheric water. A little over 10

### pe!CfN1t or3.9 cubic miles of

### it falls as precipitation each day. About 1,430 cubic miles of

### precipitation fall averthe 48 

### states annually. 

### This volume would

### be enough 

### each 

### year 

### to caver the states with about 30 inches of water. The 

### gmatest 

### avenrge yearlyprecipitation In the wolfd of460 Inches (1, 168 em) occurs at Mt. 

### Walalea/e, Hawaii. The 

### lowest 

### average annualprecipitation of 

### 1. 63 inches (4. 1 em) in the United 

### states occurred avera 42-year

### periodin Death Valley, 

### California. The 

### longest dry 

### period with no p!8Cipitation in 

### the United States occurred during 

### a 767 day period 

### from October

### 3, 1912 

## to November 8, 1914 at 

### Bagdad, Ca/ifomia. An 

### evenrge of

### 70 percent of

### the annual precipitation 

## to the coterminous 

### U.S. ( 1,001 cubic miles) 

### evaporates back into the atmosphers from landand 

### water surfaces 

### and by transpiration from 

### vegetation. The 

### T9trlaining 30

### pe!CfN1t of

### the annualpi9Cipitation ( 429 cubic miles) is transported through the 

### othersulface and subtemmean p!OCfiSSes of

### the watercycle to a 

### sti9SITI, lake, orDCEISIJ. 

### Groundwaterstorage in the cotenninous United 

### States has been 

### estimated to be 

### about 15,100 cubic miles both in the shallow groundwater 

### (less than 2,600 feet deep) 

### andan equal

## amount in the 

### groundwaterdeeper 

### than 2, 600 feet. 

### Soil moisture in the top 

### 3 feet 

### ofsoil is estimated to 

### be equivalent

## to about 150 cubic miles of

### water. The 

### United 

### states has approximately 4,560 cubic miles of 

### waterst018din freshwaterlakes. Although 

### there at8 

### about 5, 

### 540 cubic miles of 

### waterfW 

### sto/ed 

### in 

### the Great Lakes alone, aver50

### percent ofthe volume is considered to be 

### in the United 

### States. Also, about 14 cubic miles are stored in salt lakes of

### the nation. In addition, there is approximately 12 cubic miles of

### surface waters 

### strwd in stmam channels in route 

## to the oceans. Other

### sowces of 

### sulface 

### storage in the coterminous 

### states include 16 cubic miles of

### fTrJZsn waterin glaciers. The 

### stream flow 

### volume that reach the 

### oceens of the nation 

### is about 

### 1.12 cubic miles 

### per day (409 cubic miles**per~-** 

### The total 

### combined 

### surface and groundwaterflow to 

### the nation's oceans is 1. 18 cubic miles 

### par day. The 

### Mississippi Riveralone 

### contributes 0. 34 cubic miles 

### per day (annual 

### natural runoff of

### 593,000 cubic feat

### persecond). Thet8 

### are approximately2700 

### reservoirs and controlled natUI8llakes of

### mora than 5, 

### 000 acra-teat in st01age in the United 

### states. The 

### reservoirs provide 142 cubic miles of 

### storage, almost 90% of

### which occurs in 600 of

### the 1Sip68t rsservoirs. Also, them Elf9 

### approximately 50,000 res91Voirs ranging from 50 to 5,000 ac1'6-leet in st01age. It 

### is also 

### estimated that there at8 

### about 

### 2 million fatm 

### ponds in the United 

### States. Most of

### the majorraservoirs in the nation fW 

### owned 

### by the public. The 

### 8Uf81JU of

### Land Management is the manager of

### the most federal 

### dams (over 750), but most are small dams. The larger resetVoirs are managed 

### by the U.S. Army Corps of

### EngineetS, the Bunmu of

### Reclamation, and

### the 

### Tennessee Valley Authority. The Corps has built and**~** 

### 8lmotst

### 600 

### d8m8 8lld l'8(ff1(Vf]/(3

### ,th9**8U~VM~** 

### d**Reclamation~** 

### nB6IIy3(}() 

### dsm8 

### 8lld

### lfN1fJI'II'fJit, 8lld thfi1VA 11811 CMK 

### 50 

### dsmlt l1!fld 1fiiSfJMJils. Oth8r ffldtsrs/ 

### IJ(1fNICifl8 

### thllt lll!i!ll!iSifl**~** 

### dllmtt inclr.ld9 the US

## FctrHJt S8Mce 

### with abclA 400, thfl&lllleu d lrdfln AffainJ 

### with OVflf

### 300, the NaOonal PM< SeMt;e 

### with CMK- 

### thfl US 

### Fillh end 

### Wihlf& 

### S8tvioo with OVfll' 

### 115. andthe**Dei~Mment** 

### d 

## En!NriYwith 

### &!boot 30 

## cMms.. 

## WATER IN THE STATE OF OREGON Cll'eQIM iS dividtldinto 

# two d8fincll'liitlftlll ZCinfle 

### by 

### the 

### Ceteeede Renge. 

# n. tiMIJIJI precipbtion

# west of thfl**c~ ~** **~** 

### frrlm 40 

## to 140 i1lcJio$. Eutdtht**c~ ~**  

### IWI9" frrlm 10 

## to 20itlchot/#YIIIIf.**~** 

### ,...ftMIJ(II**~** 

### fCI'ttt&ril'f-- 

## it .28**~** 

### The 

## WM198 atlllUIII Nnt1ff;, 

### ebod21)**~- ~**  

### etllffl

# n.a flfllwotfc 

### cf112.000**~** 

### d 

### rivet'$ MtJ**~to** 

### eccommodftled

### the tlllfiiAI 

### tuttCif. 

# n..4W 

### owr365 wal.elflll• fNPP(Idfn 

### OlegQn 

### thtrt 

### twin the**~4lfldth&C(Qract ~**  

### dwtdMftr/ls.**~** 

### 'tlftiiiWfW!• 

### htWfl**~** 

### lfdtlnet 

## otwat« w1tll**~** 

### mcrtffllmtlllt 

### dthfl ffc1Ning 

### Wilt« clt81181tflocl8fed

### In 

## a SUCC6'1Sion 

### d stages. 

### Clilllal&ct 

### Clll8fJOIYwttlttdt11f/a hiN&

### l&tg& 

### liMin8a 

### d wafet 

### that moveptllp8/)dkdl1ll 

### O!l8r 129geathtltm81 

### hot sptfnga In 

### ttl& stat& 

### hiiN'& be6ll kllilltlfled 

### with 

### 'lllllwfrimp&nlltiJf8& thllt 818 

### 16degtHa F 

### llllxw& th&

- #llliiU8/IIIrt&mp&nltiU18. Thfl 

### lolfll**~«Supply** 

### In 

### Clrll{jiM h8s 

### not

### be6ll qlllllltlfled.. 

### Cll'eQIM 

## tw

# an $$llmttled

## ltll1.llll.llll fllllllJIJI 

### S1M'fllce wattllr supply 

### cl()JI«'

### 66 m11t1011**~-** 

### (t9.6 cdJic 

### mlfea).**~** 

## tn the 

### -Ottlll811d {/flll(/f8/Jhlc cllrtrfbiAfon 

### d 

### III'Biw**~** 

### tlltr:xJ(IIIJU 

### the etat& 181lfits 

### In antiUill Wflt6l'

### shiJrt&gf.l6 fn 

### mtlllY81881 

### d 

### th& atat&, &&pliCI8IJy 

### In MStam 

### Clr8fpt US& d llllbnl flaw

### d a1Rt'ac6**WBIC~t'$,** 

### IWff8c& 

### elOI'IIfl& In 

### f9BfiiVO/ts, 8trdl1fXIKI WBhlrSlfJIJI/&6 ttom 

### BqJif8fa 818 

### US8d 

### to m&8l 

### th& 'lf1llll' III10IJfrtJ tlllm8nds. 

### ThflfJI8#0rltverlllr9c1ifVOtagon Is ttl& 

### 1,243 mll&lollg 

### Colllnbls RNer. n fatma much 

### dOragon's notth&m

### boii:Jerwtth ttl&ststB 

### dW8Siitlgton. 

## One at ttl& 

### Cdl.mbla's 

## mB/lXtiRIIABife/J, ttl& 

### Snske RlwK forms 

## a 

## fl1fi/OI'pottJon 

### cf ttl& 

## eastsm barl8r

### d 

### Ol8goo with lcl&ho and 

### Is th& loc8flon 

### clttl& 

### 7,900 I &at 

### d&ep Hell's Canyon. 

### Thfl Columbia 

### RH6rotfg/11Bt8S 

### In 

### 8!tf«;ent st&t8S cl Washlllgton, Idaho, 8lld

## Mont- tlndIn C61111!d9. 

### 111& 

### 8VIII8fll& BIIIIUfll flow

## Is 266,(](}()cUJic**feetperftf~Cend.** Thill**volumfi~B** 

### 0.16C1Jblc 

### mJ1e6 pet'

### day. 

## Other majorwatersheds in Oregon can be divided into 

## 2.0 additional basins. They include:

IIOI"th Q)Gst Dl"81.,..es 

### 1111"-ttte 

### senq DeschUtes Jolin Day**~.~~at1Ua** 

### 6tande IIOnde 

### POWder 

### snake**Jllll.hell~ ~**  Jllll.hellr Lake' ICl-th 

### Chetco 

### Ro,.,e SoW. Q)Gst DN11131K**l.'lpq~M** !Ud-Q)Gst Drainaees**~" ~**  

### MltMheda thftt 

## empty intO 

### tht P6cific Ooten. Two dth& b8$RI$ 

# rJ**"~** 

### btiBNl tlnd 

### «*l not**d~** 

### Wf.llet 

### to the OCMtl 

### CtftO 

## t&Cfivmg $hWN. B1111$t1818 iflt(llf()tf

### lmiM that**~** 

### into I8CfiMttg $b8am$.. 

### Cll'eQIM llbol.tntla wflh CMK6,lmnstU/'8IIflku, 

### pondB, IIIIJ!I'Ilh8S,IIklu{IJB endl8fU.IIVOirs.. 

### Over 1,40Datth8m 818 

### nsm&dhlket. 

### Th&y hi!N&acomblned Sll1f8c4) 811111 

### of 6CIQ,lm 8CI8S 

### {1fN .tqiJIII8 

### 1111/&s). Hund18tiB 

### of the lalr8S 

### -1A11118171&d. 71ler&- 13 

### LDiltL.sk&a, 11 

### 8lu& Lsk&a, 10

## eta.l.Bic8S

### 8trd 10 

### Fish 

### L.M8s. Thfly

### f8fiiJ& fn Sl.l1f8t:6 8188 

### Biz& 

### ftom 

## a II'I8XImt.m c/90,000 actiiS 

### (t41**~mil&&)** 

### 8t Upper Klflmfllfl L.tlkfl 

### to C8ltJ& pond, 

### fetm pondB, 

### 8trd millponds 

### of l&ss 

### tb8n 0118 8CI8. 

### CIBI«l.Bicfl 

### Is th& 

### d8ep8st

### Isle& In 

### the Ul'llled 

### States. It

### Is 1,932 

### feet

## dNA wllh 8 

### C8p8tCfty

### at14 

### mHI/on ii!CI&-fe&t (4. 14 

### cubic mllfls) lllld8 

### siRfst:e SIN 

### at13., 139 8C18S 

### (20. 61ltlU818

### miles). Fdlowlng 

### hea1lyra/nltJ/IIllld 

### Nnt1ffdu1ng

### In 1884, MBfh8ur

### 81/d Hllm&'f

### lakes In IJ4Uih8astBm 

### Ol&goo- jolnfld 

### togsth&r

### forB1IN&t8ly&atS. 

### M8lltlwrL.ttk& endHllm8f

### t.a1te 8/8

### ags/11 

### S&p81111& hlk&a, 

### but 

### CCIIfi8Cted

### es

## part d 

### a closed b8sJn Wfltl8nd 

### systwn, wlthl.f8lh8ur 

### I..Bk& b&lng about

## so,ooo actBS. 

### 111& ltllalhflurl.ak& 

### ccmplaK

### Is stm con&ld&t9d 

### th& /arg8Bt nsfU/81 

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