The Alaska Earthquake 

March 27, 1964 

E fleets on Hydrologic Regimen 

South-Central 

Alaska 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 544-A 
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3 1819 00086456 7 

THE ALASKA EARTHQUAKE, MARCH 27, 1964: 

EFFECTS ON THE HYDROLOGIC REGIMEN 

Effects of the March 1964 

Alaska Earthquake 

On the Hydrology 

Of South-Central Alaska 

By ROGER M. WALLER 

Water-level fluctuations, long-term changes, 

and temporary effects caused by response 

of the ground water to seismic waves 

:--:· 1~ 

JAN 2 4 1967 ·' 1 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 544-A 

APR 111991 

FEB x 196' 
UNITED STATES DEPARTMENT OF THE INTERIOR 

STEW ART L. UDALL, Secretary 

GEOLOGICAL SURVEY 

William T. Pecora, Director 

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON: 1966 

For sale by the Superintendent of Documents, U.S. Government Printing Office 

Washington, D.C. 20402 - Price 30 cents (paper cover) 
THE 

ALASKA EARTHQUAKE 

SERIES 

The U.S. Geological Survey is publishing the results of 

investigations of the Alaska earthquake of March 27, 1964, 

in a series of six professional papers. Professional Paper 542 

describes the effects of the earthquake on Alaskan communities, Professional Paper 543 describes the earthquake's regional effects, and Professional Paper 544 describes the effects 

of the earthquake on the hydrologic regimen. Other Professional Papers will describe the history of the field investigations and reconstruction effort and the effects on 

transportation, communications, and utilities. 

CONTENTS 

Page 

A 1 

1 

4 

4 

4 

5 

7 

8 

Page Page 

Effects on ground water-Con. 

Long-term changes-Con. 

Homer- _ _ _ _ _ _ _ - - - _ - _ Kenai Lowland-- -__-- 

Effects on streams-Con. 

Scdiment load- _ ----.--_-- 

Effects on ground water __..____ 

Immediate effects- _ _._--__ 

Artesian wells--_ -_____ 

Shallow wells- _ _. - - - _ 

Flows of sand and mudAbstract - - - - - - _ - _ - - - - - - - - - - - - 

Introduction___ _ - _ _ -. -. -. -. .. 

Effects on lakes -___. ._--.-. - 

Ice cover __._____.-...--.. 

Wave action __.__--. -.--

Seiche waves __-..-. .-- 

Kenai area- - --- -- 

Soldatna-Sterling 

area _ _ _ _ - - -. - -. 

Anchor Point-KasLandslides-- _. - - - _ -. - _ 

Changes in water storage___ 

Damage to water-system 

structures- _ _ _ - _ - - - - - -. . 

Effects on streams--_ -_ - - --- - .- 

Ice cover ___._____---_---_ 

Ground fissures and slides-. 

Changes in flow__ _ ---- __- 

ILLUSTRATIONS 

FIGURES 

Page Page Page 

1. Map of Alaska showing affected areas _____-.-_..._ 

2. Map of south-central Alaska 

locations- __ _ - _. _ _ _. -. - -. 

3. Shattered front of Colony 

Glacier scattered on Lake 

George ice- _ -- ----.--- 

4. Wave effects on lake ice 

cover- _ _ - - - . -. _ _ _ - - _ _ . . - 

5. Ice-deposited gravel and organic ripples- - _ __ __ _. - - _ 

6. Fractured outwash delta--_ - 

10. Kasilof River stage, March 

18-April 17, 1964.. _. _ - - _ 

19. Water-level hydrographs of 

changes in wells at Anchorage__-------.------- 

20. Water-level hydrograph of 

changes at Chugiak- - -. - - 

21. Sketch map of Cordova 

showing well locations- _ _. 

22. Hydrographs of water-level 

changes on the Kcnai Lowland. _. _ - _ -. . . _. _. - - - - - 

23. Hydrographs of water-level 

changes in the Matanuskn 

Valley-. -. -. _. . _ _ - - - - - - 

24. Sketch map of Scward showing well locations- _ _. _- - - 

11. Stream-stage hydrographs of 

increased flow_- ._. .__--. 

12. Stream-stage hydrographs of 

tsunami effects- _ _ _ _ _. - - - 

13. Sediment load of Matanuska 

River, 1962 and 1964__.__ 

14. Water-level hydrograph of 

well in water-table 

aquifer _ _ - - . . -. . . - - _ - _. 

15. Large fissure and sand flow. _ 

16. Aerial view of mudflows- _. - 

17. Large sand flow- - - - - - _ - _ _. 

18. Pressure ridges on Kenai 

Lowland. _. . - - - - _. _ _ _ _ - 

7. Lakeshore slump ..___. -.--- 

8. Stream-stage hydrographs of 

streams draining lakes-. - 

9. Fissures along edge of river 

terrace- _ _. . _. - - _ - - _ _ _ _ - 

THE ALASKA EARTHQUAKE, MARCH 27, 1964: EFFECTS ON THE HYDROLOGIC REGIMEN 

EFFECTS OF THE MARCH 1964 ALASKA EARTHQUAKE ON THE 

HYDROLOGY OF SOUTH-CENTRAL ALASKA 

The earthquake of March 27, 1964, 

greatly affected the hydrology of Alaska 

and many other parts of the world. Its 

far-reaching effects were recorded as 

water-level fluctuations in gages operated on water wells and streams. The 

close-in effects were even more striking, 

however; sediment-laden ground water 

erupted at the surface, and even icecovered lakes and streams responded by 

seiching. 

Lake and river ice was broken for 

distances of 450 mile's from the epicenter by seismic shock and seiche action. The surging action temporarily 

dewatered some lakes'. Fissuring of 

streambeds and lakeshores, in particular, caused a loss of water, and 

hydrologic recovery took weeks in some 

places. Landslides and snow avalanches temporarily blocked streams 

and diverted some permanently. The 

only stream or lake structures damaged 

were a tunnel intake and two earthen 

dams. The winter coodition&-low 

The earthquake occurred March 

27,1964, at 5:36p.m. Alaska standard time and was centered in 

Prince William Sound (fig. 1). 

The land vibrated for as long as 6 

minutes from this main shock 

which had a Richter magnitude of 

8.4-8.6. Numerous aftershocks 

were distributed for about 500 

By Roger M. Waller 

ABSTRACT 

stages of water and the extensive ice 

cover on lakes and streams-at the time 

of the earthquake greatly reduced the 

damaging potential. 

Ground water was drastically affected 

mostly in unconsolidated aquifers for 

at lea,st 160 miles from the epicenter. 

Within 100 miles of the epicenter, vast 

quantities of sediment-laden water were 

ejected in most of the flood plains of the 

glaciofluvial valleys. A shallow water 

table and confinement by frost seemed to 

be requirements for the ejections, which 

were commonly associated with cratering and subsidence of the unconsolidated 

mMt>rial. Subsidence was also common near the disastrous submarine landfllides, and was probably caused by los's 

of water pressure and by latt>ral spreading of sediments. Effeets on ground water in bedroeli: were not (]elterminable 

because of laek of data and accessibility, 

particularly within 50 miles of the epi-

('enter. 

D!'f'p aquifers in unconsolidated sediINTRODUCTION 

miles (Press and ,Jackson, 1965) 

along a zone of faulting extending 

from Prince '\V'illiam Sound to 

Kodiak Island. During the main 

shock, and possibly during some of 

the first aftershocks, more than 

±0,000 square miles of land was 

lowered as much as 8 feet, and 

more than 25,000 square miles 

ments, which in most areas are under 

high hydrostatic pressure, were also 

greatly affected. Postearthquake water 

levels for a year were compared with 

long-term prequake levels to show permanent changes in an aquifer system. 

At Anchorage and in parts of the Kenai 

Peninsula, artesian-pressure levels 

dropped aH much as 15 feet. These 

lower pressures were probably caused 

either by grain rearrangement which 

increased the porosity within the 

aquifer or by a displacement of material 

that allowed water to discharge more 

freely at the submarine terminus of the 

aquifer. 

Seismically induced pressure on 

ground water was instrumental in causing most of the disastrous slides. Water quality was not changed except 

for temporary inereases in turbi<lity in 

wells and streams. The sediment load 

in streams during the April spring runoff appeared to be greatly increased 

over previous years. 

of land was raised as much as 33 

feet ( Plafker, 1965). Surface 

bodies immediately responded to 

the shaking and tilting of the land. 

Fortunately, from the standpoint 

of life and property, reservoir 

storage and streamflow were at 

their annual minimums, and a 2-

to 6-foot seasonal frost penetrated 

Al 
A2 ALASKA EARTHQUAKE, MARCH 27 , 1964 

50 

Zone of 

~ subsidence 

(After Plafker, 1965) 

Extent of appreciable effect on 

ground and surface water 

AE 

Recording stream-gage station 

Lettered station s are referred to in text 

or in other figure s 

0 50 

EXPLANATION 

100 MILES 

Zone 

~ of uplift 

(After Plafker, 1965) 

X 

Epicenter 

Observation • well 

1.-Map of Alaska showing epicenter, areas of uplift and subsidence, and extent of significant hydrologic effects. 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A3 

most of the land and water surface. 

The minimum water and maximum ice conditions reduced fluctuations and lessened the flooding 

from temporarily impounded 

streams or breached outlets. 

The extent of the hydrologic effects was possibly the greatest that 

has ever occun·ed on the North 

American continent and probably 

the greatest ever recorded. '\iV ater 

levels in streams, lakes, bays, and 

reservOirs fluctuated throughout 

most of the continent. Alaska has 

only a few recording stream-gage 

stations (figs. 1, 2), hence records 

of surface-water fluctuations are 

scarce. Several gages recorded the 

0 

Area of tectonic change 

Dashed where inferred 

(After Plajker, 1965) 

... c 

Recording stream-gage station 

Lettered stations are referred to in text 

or in other figures 

0 F 

50 

EXPLANATION 

100 MILES 

X 

Epicenter 

.15 

Observation well 

Numbered wells are referred 

to in text 

2.-Map of south-central Alaska showing locations of surface-water and ground-water observation stations. 

209-981 0 - 66-----2 
A4 

earthquake, and one gage (McCulloch, 1966) recorded most of the 

postquake seiche action on Kenai 

Lake. A few visual observations 

by witnesses supplement the available data. Hydrologic effects outside of Alaska have been described 

by Donn ( 1964), Wigen and White 

(1964), Miller and Reddell (1964), 

and McGarr ( 1965). 

Subsurface water was also a£-

fected at great distances-fluctuations of ground-water levels were 

recorded as far away as Europe 

ICE COVER 

One of the most noticeable effects of the earthquake was the 

breaking of the ice cover-as much 

as 3.5 feet thick-on most of the 

lakes in south-central Alaska. 

The ice cover was randomly broken in most lakes, pressure ridges 

were produced in the ice along the 

shoreline of many, and ice chunks 

were thrown on the beaches of others. Grantz and others (1964, p. 

6, 10) noted a generally east-west 

orientation of the pressure ridges 

and cracks in the lake ice. The extent of the ice breakage in Alaska 

is also shown by Grantz and others 

( 1964, fig. 1) and lies far beyond 

the zone significantly affected by 

the quake (fig. 1). Kachadoorian 

(1964) indicated ice breakage in 

an area of 100,000 square miles, 

and Pewe stated (1964, p. 9) that 

"Strong oscillations were noted in 

lakes on Seward Peninsula and on 

the south side of Brooks Range, 

more than 500 miles away from the 

epicenter." 

Where the lakes fronted glaciers 

(fig. 3), some glacier fronts were 

shattered and glacial ice was 

thrown out onto the ice-covered 

lake. Although Ragle and others 

ALASKA EARTHQUAKE, MARCH 27, 1964 

(Vorhis, 1966). Articles published to date on ground-water 

fluctuations include reports by the 

U.S. Coast and Geodetic Survey 

( 1964), Miller and Reddell ( 1964), 

and Waller and others ( 1965). 

Only five water-level recorders 

were operating in wells in 

Alaska-all at Anchorage. Hence, 

this great event occurred not only 

in an area of sparse population, 

but also in an area of sparse instrumentation. 

The effects described in this 

EFFECTS ON LAKES 

chapter are not at or near the epicenter. Most were observed from 

25 to 200 miles away (fig. 2). 

The writer has relied on eyewitnesses and colleagues for their 

field observations and descriptions. 

In addition, several published articles have supplemented both the 

data and the interpretations of 

various aspects of hydrology. 

The help of the author's colleagues 

in Alaska during the first few 

weeks after the earthquake IS 

gratefully acknowledged. 

~).", '.' - ~ .. -· -.r ~ 

3.- Front of Colony Glacier shattered by earthquake and scattered on Lake George · 

ice ; photograph by C. M. Hembree, April 4, 1964. 

( 1965, p. 13) reported some shattering, they found no direct proof 

that the glacier fronts of Colony, 

Portage, and Miles Glaciers calved 

extensively as a result of the earthquake. Other observers disagree. 

For example, Arthur Kennedy, 

U.S. Forest Service, who was at 

Portage Glacier at the time of the 

earthquake, noted in his personal 

diary for March 28, 1964, that 

"The glacier no longer has a sheer 

face-it is sloped upglacier from 

lake at about a 30° angle." 

WAVE ACTION 

Although most of the lake ice 

was doubtless fractured during the 

earthquake as seismic waves traversed the land, most of the ice was 

broken by wave action as the lake 

waters continued to oscillate long 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A5 

A 

B 

4.-Earthquake-induced features on lakes. A, Pressure ridges on Kenai Lowland 

lake. B, Broken ice on a lake fronting Columbia Glacier; dashed line indicates 

front of glacier; photograph by C. H. Hembree, April 4, 1004. 

after the earthquake. In some 

lakes, secondary waves were generated by subaerial or subaqueous 

landslides. The larger lakes 

showed the most extensive wave 

action and subsequent breakage of 

ice, whereas the smaller shallow 

lakes showed the most conspicuous 

pressure ridges along the shores 

(fig. 4A). A comprehensive study 

on fisheries, including effects on 

lakes, was made by the Alaska Department of Fish and Game 

( 1965). Many of their observations are included below. 

The rough texture of the lake 

ice and the abundance of jumbled 

ice blocks deposited on the shore of 

the lake fronting Columbia Glacier (fig. 4B) give the impression 

that the glacier itself had collapsed 

rather than that ice was stranded 

on the shore by the drop in lake 

level. The latter interpretation is 

that of Ragle and others (1965, 

p. 20), who then cJonclude that all 

the stranded ice disappeared as the 

level rose during the summer of 

1964, because by August the lake 

had reached the April preearthquake level again. A drop in lake 

level would have left large sheets 

of ice on the shore, much like those 

left on Eklutna Lake each winter 

as water is withdrawn for hydroelectric power generation. Thus it 

seems more likely that the stranded 

ice was deposited by seiche action 

and that by August it had melted. 

SEICHE WAVES 

Arthur Kennedy also recorded 

in his diary for March 27-28, 1964, 

an eyewitness account of wave action and ice breakage. Kennedy 

and four others were making 

depth soundings on Portage Lake, 

fronting Portage Glacier, when the 

earthquake occurred. They had 

just finished measuring the depth 

( 534 ft plus 3 £t of ice) in one hole 

when, as Kennedy states, "I first 

recall a distant roar sound then the 

lake began to violently vibrate. 

Toward the glacier I heard a very 

loud roaring." Then the ice "began to heave * * * at the hole we 

had just drilled-the water was 

going down and out of sight, then 
A6 

gushing up to the top and slightly 

over-flowing. The ice was now 

heaving up and down in big surges 

and at the same time violently 

vibrating. We noticed small 

cracks (couple inches wide) running great distances * * *. I 

could hear these cracks forming 

* * *." After the major rumbling stopped and the vibrations 

and heaving had diminished, they 

headed for shore. About 400 feet 

from shore, "The cracked ice began to get more frequent * * *. 

We edged forward to within 75 

feet of shore." As they started to 

cross this badly fractured zone, 

noting the time as 6 :15 p.m., they 

noticed ·that the ice began t'O move, 

and they heard water running. 

Kennedy continues, "Then I noticed the shoreline looked higher 

than it was before.* * * [The] 

lake surface ice was going up and 

down-I think it was oscillation.'' 

(Kennedy later wrote that he estimated this oscillation was about 5 

ft.) The party then walked 

around the west shore of the lake 

looking for an escape route. The 

ice was still surging about 3 feet at 

the lake outlet. 

Kmmedy wrote that the "interval between oscillations in time 

was about 2 minutes [from the] 

highest point to low and returnthen there was a period of about 5 

minutes between each then back to 

2 minutes * * *." Finally, at 

7: 20 p.m., they found a place to get 

ashore; at that time no noticeable 

surge was felt. This party apparently experienced the direct seismic motion as an intense vibration, 

and then felt the secondary effect 

as an oscillation (seiche) of the 

water body which continued almost 2 hours. Whether any subaqueous slides occurred in this lake 

is unknown, but if there were any, 

they would also create waves. 

Seiche action was also noted in 

other large lakes. Joe Secora, livALASKA EARTHQUAKE, MARCH 27, 1964 

A 

B 

u.--Seiche-induced features on lakes. A, Deposits of iron-stained gravel derived 

from nearshore lake ice washed up on the beach by seiche waves. B, Lake-bottom 

ripples possibly formed by organic material sorted by seiche waves. 

ing on the northeast shore of Tustumena Lake on the Kenai Peninsula (fig. 2), stated (oral commun., 

1964) that the 5-inch lake ice started "boiling" and that wave action 

lasted about 2 hours. The ice 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A7 

cracked badly, especially along the 

shore, as the water level oscillated 

about 2 feet. Other lakes which 

had notable seiche action are Skilak Lake, north of Tustwnena 

Lake; Bradley Lake, at the head 

of Kachemak Bay, Kenai Peninsula; Campbell Lake, south of Anchorage; and Eklutna Lake, south 

of Palmer. Tuthill and others 

(1964) state that "All lakes in the 

Martin River area [east of Copper 

River delta, fig. 2] experienced 

subaqueous landslides, some of 

which generated seiches." A 

stream-gage recorder, located on 

the outlet of Trail Lake (north of 

Seward, fig. 2), shows a typical 

oscillation pattern (fig. 8). 

At Kenai Lake on the Kenai 

Peninsula a water-level recorder, 

operated by a power company, registered for about 18 hours the 

seiche action caused by the seismic 

disturbance as well as wave action 

generated by landslides. McCulloch ( 1966) gives a complete description of the effects on Kenai 

Lake. 

Some lakes showed no evidence 

of wave action, even though they 

were adjacent to others where the 

ice was highly fractured. Small 

circular fracture patterns were observed in several large lakes-usually in the center, but sometimes in 

a bay or near one end. This pattern may reflect seiche action 

limited to the deeper parts of the 

lake. One large lake near the epicenter was practically devoid of 

extensive fracturing; Ralph Migliaccio (written commun., 1964) 

flew over Miners Lake a few days 

after the earthquake and noted the 

absence of fractures, although 

snow could have covered small 

cracks. The closeness to the epicenter may not have been conducive to development of damaging long-period seismic waves. 

Furthermore, the bedrock basin 

underlying the lake would respond 

less to long-period seismic shock 

waves than would unconsolidated 

material. 

Some effects of wave action continued to be visible long after the 

earthquake. At Tustumena Lake, 

isolated piles of gravel and cobbles 

on the .beach (fig. 5A) were obviously foreign to the beach and 

"·ere probably derived from the 

underside of ice blocks that had 

been washed up on shore by wave 

action. The nearshore lake ice had 

frozen into the beach prior to the 

quake. Other investigators noted 

similar deposits on other lakeshores. In the Copper River basin 

the Alaska Department of Fish 

and Game (1965, p. 35) reported 

that ridges of sand and gravel, deposited from ice, blocked some lake 

outlets. Ripples composed of organic material, probably derived 

from the beach, formed in a shallow embayment of Tustumena 

Lake at low lake level (fig. 5B). 

The ripples were about 1-2 feet 

high and about 50 feet between 

crests. These ripples may have 

been formed by the extended seiche 

action after th~ quake. Local residents did not recall having seen 

such ripples prior to the quake. 

Trees along the shoreline of 

many lakes have been scarred by 

ice. Bark was peeled off as high 

as 20 feet on trees on Kenai Lake 

(Alaska Dept. Fish and Game, 

1965, p. 29, fig. 20) and 30 feet on 

Tonsina Lake (p. 35), 

LANDSLIDES 

The glacial landscape, including 

many lakes, was modified by snow 

and rock avalanches, earth slwnps, 

and subaqueous slides which were 

triggered by the earthquake. The 

prime sources of slides were glacial 

deposits along steep valley walls 

and rapidly deposited alluvial or 

delta deposits encroaching upon 

the lakes. In general, the snow 

and rock avalanches had a negligible effect on the lakes, although 

when they occurred beneath or slid 

into a lake they generated waves 

and a few of these were destructive 

to manmade structures or ' to 

vegetation. 

The earth slumps were the most 

destructive slides. The delta 

fronts along large lakes usually 

slumped and fractured (fig. 6). 

Trees growing along such delta 

fronts and bordering alluvial fans 

6.-Fractured outwash delta and sand flows at head of Tustumena Lake. Photograph by U.S. Fish and Wildlife Service. 
A8 

were submerged (fig. 7) as the land 

subsided. McCulloch (1966) reported that the earthquake-induced slides in Kenai Lake generated waves that washed back into 

the slide area and also waves that 

hit the opposite shore. These 

waves destroyed buildings and 

scarred the trees several feet above 

ground level. 

Many coastal lakes along Prince 

William Sound and on Kodiak 

Island 'vere inundated with salt 

water and silt by the series of tsunamis that washed inland. For 

example, Potatopatch Lake at 

Kodiak is now part of the tidal 

flats. Some of these lakes had been 

the source of fresh-water supply 

for nearby residents or were important for fresh-water sport fishmg. Now the lakes will remain 

saline until the salts have been 

flushed out. 

CHANGES IN WATER 

STORAGE 

Secondary effects of the Alaska 

earthquake temporarily drained or 

dewatered many lakes. Lake 

levels were lowered either by spillage and overflow during seiching 

or by drainage through fracture 

systems in the lake basin. Gages 

on the Bradley Lake and Trail 

Lake outlets (fig. 2) recorded a 

temporary loss in stream stage 

(fig. 8), reflecting lowered lake 

levels. Discharge from Kenai and 

Tustumena Lakes also decreased 

for several hours to several days 

after the quake. The Finger 

Lakes in the northern part of the 

Kenai Low land (fig. 2) showed 

the only long-term change in storage capacity. These lake levels 

were five feet below their prequake 

levels by October 26, 1964 (Alaska 

Dept. Fish and Game, 1965, p. 27, 

fig. 19). A small lake north of 

Kenai started losing water as late 

as mid-June. 

ALASKA EARTHQUAKE, MARCH 27 , 1964 

7.-Trees submerged by minor earth slump along lakeshore. 

fw 

w 

"-

3 

27 

Trail River near Lawing 

Station G 

Bradley River near Homer 

Station J 

28 

MARCH 1964 

29 

8.-Hydrographs of two streams draining lakes on the Kenai Peninsula. 

See figure 2 for locations. 

Many lakes were perched above 

the seasonal areal water table at 

the time of the earthquake and 

thus were able to drain through 

seismic fractures in the frozen unconsolidated material. The lake 

levels also were lowered from 

seiche action. The prolonged 

wave action, as long as 2 hours on 

Portage and Kenai Lakes, repeatedly washed water over low 

points of the shoreline or out 

through the normal outlet of the 

lake. Hence, some lakes were partially or completely drained. Former levels were restored within a 

few days by streams or within a 

few weeks by snowmelt. 

Tectonic tilting may have 

changed the storage capacity in 

some lakes, particularly those long 

lakes that lie parallel to the direction of tilting. Kenai Lake was 

tilted to the east, and Skilak and 

Tustumena Lakes were possibly 

tilted eastward 1-2 feet, as inferred from regional tectonic subsidence (Grantz and others, 1964). 

Field investigations of these lakes 

and Eklutna and Bradley Lakes 

were inconclusive because of lack 

of prequake control. Hence, a 

program of establishing bench 

marks to determine future tilting 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A9 

was established on 17 large lakes in 

south-central Alaska (Hansen, 

1966). 

DAMAGE TO WATERSYSTEM STRUCTURES 

Two manmade lakes were 

drained because of the earthquake. 

The rupturing of the earth-filled 

dam on Campbell Lake, at the 

mouth of Campbell Creek south of 

ICE COVER 

The ice cover on many streams 

was broken during the earthquake. 

However, the ice cover was not 

broken extensively; seiche waves, 

therefore, presumably did not develop in the streams and breakage 

must have resulted from seismic 

shock. The ice remained unbroken 

on the Copper River where it flows 

through Woods Canyon-a bedrock gorge about 70 miles east of 

the epicenter. Bedrock is known 

to respond less than unconsolidated material to seismic shock; 

thus, the lower amplitude of the 

ground response may explain why 

the ice was not broken in this bedrock gorge. Other streams were 

routinely checked for this relationship during air reconnaissance, but 

no consistent pattern was foundperhaps because the other major 

streams observed do not flow in 

such a bedrock gorge. 

GROUND FISSURES AND 

SLIDES 

Extensive fissuring and associated earth flowage were the most 

prevalent effects of the earthquake 

along the streams in south-central 

Alaska. Fissuring was fairly random throughout the area but was 

very noticeable because of the exAnchorage, allowed the water to 

drain out. The dam on a lake near 

O'Malley Road south of Anchorage also was breached. 

Perhaps the most serious and 

costly damage was the displacement of a tunnel-intake structure 

in Eklutna Lake. The structure 

was partially displaced either by 

wave action or by differential subsidence of the lake floor; the earth 

below the log and earth-filled dam 

EFFECTS ON STREAMS 

posed sand and gravel bars of the 

braided streams. Some fissures extended across stream flood plains, 

but most were on adjacent terraces 

parallel to the streambanks (fig. 

9). Silt, sand, or gravel were 

ejected along many of the fissures 

and formed ridges on one or both 

sides, or sometimes formed flows 

or sheets which extended many 

feet from the fissures. 

Landslides or snow avalanches 

blocked several streams, notably 

had also subsided. A peripheral 

area of lake bottom about 200 feet 

wide was exposed because the lake 

was at a low level from winter 

withdrawals. This area subsided 

because of compaction or lateral 

spreading of the offshore la;kebottom silt. It appears that the 

submerged intake-structure was 

disturbed primarily by subsidence, 

although seiche action may have 

contributed to the damage. 

the Klutina River in the Copper 

River basin, Ship Creek near Anchorage, and the Tiekel River and 

several other streams along the 

Richardson Highway north of 

Thompson Pass. A snow and 

earth slide on the Klutina River 

about 9 miles below Klutina Lake 

(fig. 2) apparently did not block 

the river immediately, but, as reported by the Alaska Department 

of Fish and Game (1965, p. 43, fig. 

33), "Before the spring breakup 

9.- Fissures on terrace parallel to Copper River bank. Photograph by R. M. 

Migliaccio, September 14, 1964. 
AlO 

the river had begun to cut a new 

channel around the slide. By midsummer the channel re-routing 

had been completed * * *." 

A minor snow slide on Ship 

Creek about 4 miles upstream 

from the lowland caused much 

concern and anxiety to water-supply officials, because the slide temporarily dammed the creek and 

therefore cut off the water supply 

for the city of Anchorage and 

nearby military bases immediately 

after the quake. It was almost 48 

hours before normal flow resumed 

at the diversion dam, and about 10 

days before downstream flow returned to prequake levels. 

There were numerous reports of 

slides that blocked other streams; 

one report of a slide on the Copper 

River received national news coverage. The writer believes that 

most such reports of dry riverbeds 

were based on aerial observations 

of extensive mudflows subsequently frozen on top of river ice 

in some reaches of the rivers. In 

other instances, where snowslides 

appeared to block a channel completely, the slide had not broken 

the ice cover. 

CHANGES IN FLOW 

Changes in streamflow were controlled by fissures in and adjacent 

to streambeds and by landslides 

and snow avalanches. The slides 

commonly did not block the flow 

for long, but some residual effects 

persisted for longer periods. For 

example, Ship Creek, which was 

flowing about 15 cfs (cubic feet per 

second) , was dammed for about 18 

hours. During this time the underflow in the streambed below the 

dam continued to drain, and the 

upstream supply was entirely diverted for public use at the dam. 

Thirty -six hours after the earthquake the creek supply at the dam 

exceeded the diversion and began 

to recharge the drained -out creekALASKA EARTHQUAKE, MARCH 27, 1964 

bed. It took about 10 days for the 

creek to regain its prequake flow, 

and by then snowmelt began to 

augment the base flow of the 

stream. 

Hydrographic loss in the reach 

of Ship Creek, a very flat alluvial 

fan, was increased by ground fissuring in and adjacent to the 

stream. Flow in a neighboring 

stream, Chester Creek, which depends entirely upon ground-water 

discharge in late winter, decreased 

from 12 to 4 cfs on March 31, and 

recovered to 13.6 cfs by April 6. 

The flow decrease is attributed to 

loss through fractures in the 

streambed and to decreased outHow of ground water. The latter 

is believed to be more significant, 

because artesian levels in the area 

were drastically reduced immediately after the quake. 

Changes in flow, particularly 

losses, were noted in larger streams 

also, but ice cover inhibited accurate observations. Extensive 

areas of fissuring on adjacent 

banks ·were noted along many 

streams. The most conclusive evidence for streamflow loss ·was 

noted where a stream drains a lake. 

The U.S. Geological Survey has 

installed stream-gage recorders on 

outlets of several lakes in this region (fig. 2). The hydrographs 

shmvn in figure 8 illustrate the 

drop in height of the water surface 

which indicates a decrease in 

streamflow. 

Flo'v in the Kasilof River, 

which drains Tustumena Lake 

(fig. 2), was so reduced that many 

observers reported that it was dry. 

The Alaska Department of Fish 

and Game (1965, p. 29) stated that 

"Its flow was halted to such an extent that a biologist was able to 

walk up its channel the following 

day wearing overshoes." A plot of 

the river stages at the Geological 

Survey gaging station on the Kasilof River bridge (fig. 2) is shown 

on figure 10. The plot shows diminution of flow, from 566 to 70 cfs, 

by March 30. 

The loss of flow in the Kasilof 

River and in other streams draining lakes is due primarily to decreased outflow from the lakes. 

Many such streams recovered their 

flow slowly because, like Ship 

Creek, the subsurface sediments 

had to be recharged before the 

streams could resume their normal 

flow. 

An increased flow was also recorded in some streams, but it was 

not as common as stream losses. 

The hydrographs of three streams 

in south-central Alaska which 

showed an apparent increase in 

flow are shown in figure 11. The 

increased flow of Power Creek is 

believed (M. J. Slaughter, written 

commun., 1964) to be "* * * the 

Kasilof River near Kasilof 

Station F -

1819202122232425262728293031 1 2 3 4 56 7 8 91011121314151617 

MARCH APRIL 

10.-Water-level stage of Kasilof River from March 18 to April 17, 1964. See 

figure 2 for location. 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA All 

27 

Little Susitna River 

near Palmer 

Station E 

28 

MARCH 1964 

29 

11.-Hydrographs of three streams in 

south-central Alaska. See figure 2 

for locations. 

result of released water stored behind an ice dam upstream prior to 

the quake." The Little Susitna 

River had an increased flow which 

perhaps is also attributable to release of water from behind ice constrictions. Here, as in most of the 

streams, the seasonal warming 

trend was beginning, and snowmelt began to mask the prolonged 

earthquake effects in a few days. 

The flow of Snow River was unusual. The water level, in the stilling well at least, rose more than a 

foot in a few minutes with no apparent surge. The water then 

gradually receded to about its former level in 24 hours. A possible 

mechanical cause of this unusual 

fluctuation was reported by J. P. 

Meckel, hydraulic engineer (oral 

commun., 1965). He believes that 

the bubble gage did not respond to 

the rapid upward surge caused by 

the seismic shock because the gage 

is "sensitized to normal fluctuations." Probably the water was 

rapidly forced up into the stilling 

well, as noted in wells and in sand 

fountains, and then gradually 

drained out. 

The Tiekel River north of Valdez was dammed by a snowslide 

200--98.1 0---j66---3 

and nearby Tonsina River was 

dammed by ice jams; both had to 

be opened with explosives to prevent highway flooding. 

Gages on three streams on 

Kodiak Island recorded the tsunamis that were so destructive at 

Kodiak, Old Harbor, and elsewhere. Figure 12 shows two of 

these hydrographs that reflect the 

earthquake shock, tsunamis, and 

high tides. Tsunamis traveled up 

these streams at least five times as 

recorded at the Myrtle Creek gage. 

The float was hung up by the third 

wave, but it registered subsequent 

7- and 9-foot surges. 

Tectonic land subsidence or uplift may eventually steepen or lessen, respectively, the gradients of 

these streams and thus alter the 

streamflow pattern. The .pattern 

alteration may not be recognizable 

in the immediate years ·ahead except in areas of extreme change, 

such as the part of Montague Island (fig. 2) which was uplifted 

33 feet. The most immediate and 

noticeable effect in subsided areas 

is the greater extent of tidal inundation and backwater in coastal 

streams. This condition was disastrous to fish-spawning areas and 

has been investigated by the Alaska Department of Fish and Game 

( 1965). U.S. Geological Survey 

recorders on the three streams on 

Kodiak Island now register most 

high tides, whereas before the subsidence they recorded only extreme 

high tides. 

Other gages in south-central 

Alaska (fig. 2) responded to the 

earthquake shock, but either the 

records were disrupted or the float 

was too solidly frozen into the stilling well to show postquake effects 

clearly. 

The U.S. Geological Survey operated recorders in other parts of 

Alaska. The northernmost station 

that registered the shock was on 

High tide 

5 

~ganik Rive1

r 

Station L 

0.5 mile upstream 

from mouth 

High tides 

I "-... 

t;j 

quake Earth- ~~"';: 

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} l 

I Terror River 

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from mou,t

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27 28 

MARCH 1964 

29 

12.-Hydrographs of two Kodiak Island 

streams showing effects of tsunamis 

and of land subsidence. See figure 

1 for locations. 

the Tanana River at Tanacross 

(fig. 1, location A). Three other 

stations west and north of Cook 

Inlet (fig. 1, locations B, C, and 

D) did not record the seismic shock 

even though they were within 200 

miles of the epicenter. One other 

instrument, north of Bristol Bay 

and rubout 400 miles WSW from 

the epicenter, also was not visibly 

affected. In contrast, 19 of the 30 

hydrograph stations in southeastern Alaska, some as much as 700 

miles distant, recorded effects of 

the shock wave. Six stations near 

tidewater recorded the tsunamis. 

One station on a lake recorded 

seiche action for several hours. 
A12 ALASKA EARTHQUAKE, MARCH 27, 1964 

10,000 r-------.,----------,-1-------,-----------n 10,000 

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EXPLANATION 

-o-o-o1962 discharge 

-·-·-·- 1964 discharge 

1962 concentration 

1964 concentration 

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13.-Suspended-sediment concentration and discharge in the Matanuska River near 

Palmer, 1962 and 19!>4. 
EFFE·CTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA Al3 

Several hydrographs indicate an 

increase of streamflow immediately after the trace of the shock. 

However, V. K. Berwick, hydraulic engineer, reported (written commun., 1965) that an analysis of precipitation data indicates 

that rainfall occurring on March 

27 and subsequent days probably 

caused the increases. The writer 

concurs with this analysis because 

data from 12 stations showed a beginning rise in stream stage before 

the quake, whereas only 5 stations 

show a rise coincident with the arrival of the shock wave. Probably 

the shaking motion, although not 

generally felt in bedrock areas of 

southeast Alaska, disturbed the 

ice-choked parts of some of the 

streams and thus caused a temporary rise in streamflow. Two 

hydrographs, which showed an 

appreciable drop after the disturbance, probably reflect temporary 

damming of the streams by ice. 

SEDIMENT LOAD 

As a result of the intensive fissuring and the ejection of sediments into the streambeds, the deposition of landslide material onto 

the ice-covered streams, and the 

erosion of loosened material on the 

mountain slopes, the spring runoff 

transported unusual amounts of 

sediment. The sediment load of 

the streams was greatly increased, 

but the increase was apparently of 

short duration. Three stations for 

measuring daily sediment load 

were in operation in south -central 

Alaska. The station at the highway bridge on Twentymile River 

at Portage (fig. 2) was destroyed, 

however, and was discontinued 

after the observer was evacuated. 

EFFECTS ON GROUND WATER 

IMMEDIATE EFFECTS 

The initial seismic shock and the 

associated seismic waves immediately altered the hydrologic regimen. Short-term effects included 

(a) surging of water in wells, (b) 

extrusion of water, mud, and sand, 

(c) failure of well system, and (d) 

turbidity of water in wells and 

sprmgs. The long-term effects, 

resulting from physical changes 

in the aquifers, are discussed in a 

later section ( p. A17). 

ARTESIAN WELLS 

The immediate reaction of water in artesian wells near an epicenter is due principally to the stresses 

imparted to the aquifer. Ferris 

and others (1962, p. 87) summarize 

previously published American 

works on such fluctuations and 

state that when shock waves from 

an earthquake reach an aquifer 

"* * * there will first be an abrupt 

increase in water pressure as the 

water assumes part of the imposed compressive stress, followed 

by an abrupt decrease in water 

pressure as the imposed stress is 

removed. In attempting to adjust to the pressure changes, the 

water level in an artesian well first 

rises and then falls." 

Of the five recorders operating 

at Anchorage, four were on artesian wells. However, the instrumentation was not sufficiently 

damped to register accurately the 

sudden and intense fluctuations 

in water level caused by the seismic 

impulses on the aquifers. Two 

records were unintelligble. One 

well recorded 6 feet of fluctuation 

before the pen was flipped off the 

chart. The fourth instrument operated during the quake and for 8 

hours recorded continuous fluctuaThe station on the Ninilchik River 

bridge north of Homer (fig. 2) 

continued in operation, but recorded no significant change, probably because the stream flows 

through a lowland having no steep 

valley slopes and because the site 

is about 150 miles from the 

epicenter. 

The long-established station on 

the Matanuska River bridge (fig. 

2) showed a large increase in sediment load during the month of 

April (fig. 13). A plot ofthe suspended-sediment concentration 

shows that in April 1964 the 

stream carried five times the 

amount of sediment it carried in 

1962 during a comparable period 

and flow. L. S. Leveen (written 

commun., 1965) stated that suspended-sediment loads during the 

summer were normal. 

tions of the water level. The total 

fluctuation, estimated to exceed 24 

feet, is some indication of the fluctuations of this and other artesian systems of south-central 

Alaska. 

SHALLOW WELLS 

Shallow wells, as considered 

here, are wells that tap near-surface aquifers that are not overlain by a confining layer. Water 

in these water-table wells does not 

respond to seismic waves as does 

water in artesian wells because it 

is free to move vertically as the 

pressure wave passes through the 

aquifer. However, within the region of intense ground motion, the 

inertia of the water body and the 

oscillations set up in the ground 

water produce movements that oppose the g r o u n d movement. 

Hence, unconfined ground water, 
A14 

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1-

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8.10 

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Well Anc 3168 

Depth 15ft 

Altitude of land 

surface 98 ft 

~Aftershocks 

\Earthquake 

5:36PM 

-8.16 

262728293031 1 2 3 4 5 6 7 

MARCH APRIL 

14.-Hydrograph of water-table well 

Anc 316B, south of Anchorage, from 

March 26, 1964, to April 7, 1964. 

as w.ell as bodies of surface water, 

probably tends to oscillate but the 

the ground-water motion is 

damped by friction within the 

aquifer. 

The widespread water fountains 

and flows of sand and mud were 

erupted from the water-table zone. 

These extrusions indicate that 

high pressures must have existed 

in the water-table aquifer, and 

thus a temporary confining layer 

must have been present. 

The behavior of unconfined water levels during an earthquake 

is illustrated by an excellent record obtained at Spenard, south of 

Anchorage, in a well tapping a 

zone of water-saturated sand 7.8-

ALASKA EARTHQUAKE, MARCH 27, 1964 

15 feet below land surface. The 

depth of frozen ground probably 

was about 5 feet at the timehence the water was not confined, 

because there was about 3 feet of 

unsaturated sand between the forzen layer and the water table at 

7.8 feet. The record (fig. 14) 

shows that in this well the water 

truble fluctuated less than a foot. 

The area near this well, and the 

well-known Turnagain area, 

where similar conditions prevailed, yielded no signs or reports 

of sand or water ejections. In contrast, stream valleys and high tidal 

marshes at Anchorage did have 

areas of ejected water and mud, 

because there the water table was 

confined by the seasonal frost. 

FLOWS OF SAND AND MUD 

"Sand-spout,'' and "mudspout," or "mud fountain," "mud 

volcano," "sand blow," "sand boil," 

"mudvent," crater, and several 

other terms have ·been used to 

describe certain features which 

appear during most great earthquakes and are associated with 

water-saturated sediments. W ater-borne material is ejected from 

fissures during the earth movements and, in some places, the flows 

continued long after the shocks 

had passed. In areas where the 

ground water is confined, as in . 

river ·beds, the increased hydrostatic pressure is also relieved. 

The pressure head raises or otherwise disturbs the streambed, and 

the sedimenrts are saturated to 

the quicksand condition. Probably every major valley in southcentral Alaska showed evidence of 

fissures and flows. 

Lemke ( 1965, p. 121) reported 

that the lower part of the J ap 

Creek fan at Seward fissured when 

"loose gravels were compacted by 

vibratory action during strong 

ground motion. Where the water 

taible was high the frozen ground 

surface was ruptured." Ground 

water was released under hydrostatic pressure to heights of 6 feet 

and sand boils developed. The 

ejected sediment came principally 

from well-sorted sand lenses, one 

of them 12.5 feet deep. Lemke 

also suggests that differential com15.-Large fissure and sand flow in the Skilak River valley near Tustumena Lake. 

Split tree indicates about 3-foot displacement. Note 6- and 8-inch rocks ejected 

upslope. 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A15 

' ' 

-· 

-

400± FEET 

s 

\ 

16.-Aerial view of extensive mud flows and fissures in the Placer River valley near Portage. 

paction, controlled by the irregular buried bedrock surface, limited the areas of fracturing to the 

outer parts of the fan. In contrast to the J ap Creek alluvial fan, 

the Lowell Creek fan at Seward 

did not fissure extensively. The 

Lowell Creek fan has been largely 

dewatered, and only near sea level, 

where the water table is near the 

surface, were fi-ssures formed. 

Fissures on deltas also occurred 

only on the lower slopes. In those 

areas, however, the fissures are undoubtedly tensional f e a t u r e s 

formed behind the free face of the 

delta front (fig. 6). Furthermore, 

the hydrostatic pressures in the 

acquifers are less confined because 

the water table is very near the 

surface on the lower slopes. A 

typical fissure parallel to the shore 

of the delta in the Skilak River 

Valley is shown in figure 15. The 

extruded material-silt, sand, and 

gravel-was deposited principally 

downslope.· 

Fissures and flows in stream valleys and on flood plains were locally controlled by the configuration of the water table. Constrictions in the valley floor and the 

points of change in slope of the 

stream are places where the 

ground-water movement is restrained; hence, the water level is 

nearer the surface than elsewhere 

in the valley. At such places fissuring and outflows seemed to be 

more extensive than elsewhere. 

One extensive area of fissuring and 

flowage is in a poorly drained part 

of Placer River Valley, near 

Portage (fig. 16). 

In some places (fig. 17, p. A16), 

the outflows removed so much rnaterial from the ground that local 

collapse and probably general subsidence occurred. Although collapse craters generally had outflow channels, some craters formed 

where there was no evidence of discharge. Some of these were on 

river terraces, but most were on 

flood plains. This restricted occurrence indicates either that the 

underlying material was compacted or that the fine material 

was removed by ground water and 

ejected some distance from the 

crater. Davis (1960, p. 499) noted 

extensive separation between craters and flows at Huslia in 1958, and 

found that the distance between 

one crater and the nearest flow was 

600 feet. It is also possible that 

these craters formed long after 

the earthquake. R. M. Migliaccio 

(oral commun., 1965) stated that 
A16 ALASKA EARTHQUAKE, MARCH 27, 1964 

17.-Sand flow from 2-foot fissure more than 200 feet long, parallel to Tustumena 

Lake shore. Sand flowed mainly to left toward the lake. 

some crarers were first noted after 

the early-summer stream runoff. 

Another effect of the seismic 

waves on shallow water confined 

by seasonal frost was formation of 

pressure ridges along the margin 

of a long, large swamp representing an abandoned glacial-meltwater channel south of Tustumena 

Lake (fig. 18). The ridges were 

observed from the air and were 

seen to be overthrust layers of the 

surface vegetal material about 3 

feet thick and jutting upward as 

much as 10 feet in the air (on the 

basis of comparison with the 

height of a fleeing moose) . The 

linearity of the pressure ridges 

suggests tectonic movement, but a 

more logical explanation is that 

the compression was caused by the 

oscillation of the frozen surface 

layers over a water-saturated 

substratum. 

An example of the pressures 

that can be created by compression 

of the shallow water table was 

noted at Anchorage 2 weeks after 

the earthquake. The floor of a 

small swale in southwest Anchorage bulged, and many residents 

thought that a volcano was about 

to erupt. At that season, however, 

the shallow ground-water table 

characteristically begins to reflect 

annual spring recharge. The seasonal frost cover, and possilbly an 

abnormal constriction down gradient at a road crossing confined the 

increasing head of water, and the 

ground rose about 2 feet in a 20-

foot area. 

A shallow water table apparently contributed to the extensive 

effects noted in unconsolidated 

material in south-central Alaska. 

Where the water table was somewhat lower than the seasonal frost 

or a semiconfining zone at the land 

surface, there was little surface 

evidence of earthquake effects. 

DAMAGE TO WELL STRUCTURES 

The failure of some well systems 

was mainly due to sanding or silting of the pump column or to the 

differential movement of well casings and the surrounding rock. 

Most of the wells are unscreened 

and have a foot or several feet of 

uncased hole. These conditions 

readily lend themselves to cave-ins 

or slumping of the walls under 

earthquake stress. Fine-grained 

material washed into the well by 

dilation and compression of the 

aquifer may also contribute, but 

normal pumping of wells probably 

causes a greater flushing action 

than that of the earthquake. Resumption of pumping after the 

quake brought fine material into 

the system and caused turbid water 

or malfunction of the pump. 

Other wells that have pumps requiring a full pipe of water for a 

prime probably lost their prime 

during the violent water fluctuation in the well. Thus, erroneous 

reports of dry wells were as common as they usually are after most 

quakes. 

At Anchorage three city wells 

were damaged. The most significant damage was caused by the 

failure of artificial fill at the city's 

main well. The resulting movement destroyed the pumphouse 

and bent the well casing. The casing was straightened and a new 

pumphouse was built. A well near 

the large Turnagain slide was destroyed by lateral movement. The 

third well, also in the Turnagain 

area, was abandoned because of 

damage, apparently from lateral 

movement. 

At Seward the three city wells 

( 4-6; see fig. 24, p. A25), all believed to be about 100 feet deep, 

were ruined by ground movement and fissuring. Wells Sew 

4 and 5 (old City 1 and 2, respectively) would not pump water 

after the earthquake. When an 

attempt was made to pull the pump 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A17 

18.-Pressure ridges in a long, large swamp (Kenai Lowland). Ridge of overthrust material (or) in foreground is about 500 

feet long. 

columns, the binding of the column 

and casing was so great that the 

casing pulled apart in Sew 4 and 

the column would not budge at 

Sew 5-probably because of the 

horizontal shift of part of the alluvial fan. Well Sew 6, about 10 

feet higher than Sew 4 and 5, survived the earthquake, but near the 

end of April 1964, the pump turbine jammed because the ground 

moved or settled and caused a 

gradual increase of friction. The 

pump column could not be pulled 

because of a casing offset. In the 

meantime, the U.S. Army Corps 

of Engineers drilled replacement 

wells adjacent to S.ew 5 and 6. 

These two new yvells had water 

from a depth of 34 feet intermittently to a total depth of 200 feet. 

The wells were developed in the 

best part of the aquifer, at about 

160-170 feet, and had water levels 

of about 21 feet below the surface-a confined aquifer is thus 

indicated. 

At Valdez a 24-foot well was 

bent seaward by land movement, 

and its casing was sheared at a 

threaded joint 15.5 feet below the 

surface. One of the city wells 

was damaged, possibly by an electric failure during the quake, but 

the other was operable and was 

being used to pump water into 

temporary surface pipe for distribution. 

LONG-TERM CHANGES 

The long-term effects on the hydrology of south-central Alaska 

i n c l u d e temperature changes, 

changes in the chemical quality of 

the water supply, and the residual 

lowering of water-level or artesian 

pressures. The lower water levels 

or lower artesian pressures were 

the most noticeable effect and presumably stem from changes in discharge rates or transmissibility of 

aquifers. 

Locally, notable subsidence of 

land, not related to tectonic subsidence, marks anoth.er residual effect. This subsidence is generally 

associated with areas of extrusion 

of water and mud. Some subsided 

areas, such as at Portage and 

at Anchorage (Waller, 1966b), 

showed no surface evidence of loss 

of water or sediment; subsidence 

probably reflects compaction of the 

aquifer after loss of hydrostatic 

pressure in the higher reaches of 

the aquifer. 
A18 

ANCHORAGE 

The artesian aquifers at Anchorage are composed o£ sand and 

gravel interbedded with clay and 

glacial till (Cederstrom and others, 1964). The deposits are as 

much as 500 feet thick and extend 

under the adjacent Knik and 

Turnagain Arms o£ Cook Inlet 

(fig. 2). Periodic water-level 

measurements have been made in 

50 water wells in the Anchorage 

area-some dating back to 1951. 

Hence, preearthquake water-level 

records, frequent measurements 

made after the earthquake, and 

previous studies (Waller, 1964) 

have all contributed to a thorough evaluation o£ the long-term 

effects o£ this earthquake. A report on the earthquake effects at 

Anchorage is presented in detail 

elsewhere (Waller, 1966b). A 

u.J 

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~ 165 __J 

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0 

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70 

Dec. 

Well Anc 505 

Depth 453ft 

Altitude of land surface 166 ft 

June 

1958 

I 

Dec. June 

1959 

Dec. 

ALASKA EARTHQUAKE, MARCH 27, 1964 

summary o£ the preliminary findings is presented here. 

The 50 observation wells were 

measured periodically, starting a 

few days after the earthquake. 

All but one o£ the Anchorage observation wells indicate changes to 

the water-table and artesianaquifer system. One well taps the 

Tertiary bedrock about 400 feet 

beneath the glacial drift. 

Almost all the well measurements show that the pressure level 

was lowered as much as 24 feet 

but that recovery started immediately. Within about 6 months the 

pressure had recovered completely 

or had risen to a new level o£ stability. The new pressure level in 

about one-third o£ the wells is as 

much as 15 feet lower than prequake levels. In about two-thirds 

o£ the wells the level is within 5 

............. ____ _ -------......... ...___ 

June 

1960 

Dec. June 

1961 

Dec. June 

1962 

Dec. 

feet o£, or at the same level as, the 

preearthquake level. Representative hydrographs o£ three wells 

tapping glaciofluvial aquifers (fig. 

19) show the range of residual 

changes. The areal distribution 

o£ the measured changes o£ water 

level in the wells is not entirely 

consistent, but it implies that most 

of the changes occurred in areas 

underlain by thick estuarine or 

lake deposits o£ fine sand and silt. 

In several wells, the postquake 

water levels are higher than they 

were before the earthquake. These 

wells are located within the area o£ 

influence o£ the city and military 

well fields. Because all wells 

drawing water from the Anchorage artesian system were suddenly 

without power £or pumping, the 

artesian system had a chance to 

partially regain its natural prede-

-----~ 

I 

I 

\~r I I 

I 

June 

1963 

Dec. June 

1964 

Dec. June 

1965 

19.-Hydrographs of three Anchorage wells, 1958-65, showing residual changes in artesian pressure after the earthquake. 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A19 

velopment pressure. However, 

power was restored sporadically, 

and most wells were back in operation within 2 or 3 days. They generally were pumped for greater 

lengths of time than was customary before the earthquake because of leakage in the distribution systems. As a result of this 

disruption of the normal pumping pattern, some water levels rose 

above prequake levels. Many 

more water levels were extremely 

low during the first few weeks 

owing to overdraft of public-supply pumping and the general lowering due directly to the earthquake. 

After the summer recharge period (note annual fluctuations in 

the hydrographs, fig. 19), the residual changes in the water levels 

could be ascertained. A full year's 

record now confirms the net lowering of water levels. The residual 

change to a lower pressure level 

implies that recharge has decreased, or water has found new 

outlets and is moving through the 

aquifer at a faster rate. Because 

of the lowered pressures and the 

inference that the water movement 

in the aquifer has increased, the assumption is made that either the 

permeability of the aquifer has 

been increased by an increase in 

pore size, or a change has taken 

place in the outlet of the aquifer 

so that water can leave the aquifer 

more readily. Fracturing of the 

subsurface confining beds of clay 

or glacial till is not considered 

probable, nor would it cause the 

variable drop in pressure. The 

aquifers at Anchorage are interconnected ( Cederstrom and others, 

1964; Waller, 1964), hence, additional interconnections would have 

little area-wide effect. Fracturing 

at depth in the water-saturated deposits also seems unlikely. The 

natural discharge may have been 

increased locally by removal or rearrangement of the estuarine silt 

cover overlying sub-inlet discharge zones of the aquifer. The 

porosity of the sand and gravel 

aquifers may have been increased 

locally by flushing of fine material 

into wells or areally by aquifer expansion owing to an imposed stress 

from seismic waves or the tectonic 

subsidence (about 3.7 ft) and horizontal movements. 

Observation of the water level 

in the one well that taps a Tertiary 

aquifer ( Anc 1, fig. 19) indicates 

that that aquifer also underwent 

some changes. The lower water 

level seems to be permanent. 

Water in the Pleistocene Bootlegger Cove Clay was a significant 

factor in the extensive sliding that 

occurred at Anchorage. Water 

pressure in sand lenses within the 

clay presumably was increased by 

seismic motion until failure occurred and the land moved laterally 

toward the sea. Pore pressure 

measured in the clay since the 

quake shows that some areas are 

gradually losing the pressure existing after the quake, whereas a 

few others show pressure buildup. 

Sea water may be encroaching 

beneath Fire Island in Cook Inlet 

off Anchorage, inasmuch as the 

chloride content has steadily increased since the earthquake. One 

of the wells on the island had been 

drilled into a salt-water-bearing 

formation several years previously but was reportedly cemented 

or sealed off. Possibly the earthquake disrupted this seal, rather 

than the confining layer over the 

salt-water formation, and now salt 

water is leaking into the upper 

fresh-water aquifer that supplies 

the other wells. Observation of 

these wells is continuing. 

CHUGIAK 

The ground-water conditions in 

the Chugiak area, adjacent to and 

northeast of Anchorage (fig. 2), 

are similar to those at Anchorage 

except for a greater percentage of 

till and a lesser thickness of glacial 

drift. The effects of the earthquake in this area were similar to 

those at Anchorage. Dale Pierson, Chugiak well driller, reported 

(The Johnson Drillers Jour., 1964, 

p. 5) that "Locally * * * numerous wells went dry. Others have 

become muddy and silty." A well 

Pierson was drilling at 102 feet 

reportedly was offset between the 

50- and 60-foot level. The statement regarding numerous dry 

wells has not been verified, but 

because there are many shallow 

dug wells in this area and they 

were at their seasonal low-water 

level, the statement does appear 

reasonable. The water levels of 

six observation wells in this area 

were periodically measured before and after the earthquake. 

Two of the four water-table wells 

showed possible effects of the 

earthquake-a temporary rise in 

water level of a few feet, probably 

owing to recharge from the surface through ground fractures. 

Of the two wells which tap artesian aquifers, one was little affected and the other (well 120) 

showed a decline in water level of 

about 10 feet (fig. 20, next page). 

Pree,arthquake water-le,vel data 

are presented in Waller ( 1960). 

COPPER RIVER BASIN 

Effects on the aquifers in the 

Copper River basin were reflected 

in water levels in wells (Ferrians, 

1966). The following description 

is drawn largely from Ferrians' 

findings. 

The Copper River region is 

within the permafrost zone of 

Alaska and is characterized by a 

lack of fresh-water aquifers. 

Moreover, the sparse development 

of water wells on the aquifers has 

restricted the interpretation of effects. Water levels in several 

wells reportedly lowered appre-
A20 

ciably, but generally the levels 

were restored in a few days. Three 

wells in the Glennallen area were 

reported to have gone dry. These 

were probably shallow wells which 

had low water levels at this time of 

the year. 

The apparent negligible effect of 

the aquifers in this region, as close 

to the epicenter as Anchorage or 

the Matanuska Valley, is probably 

due to the presence of deep permafrost. Stream flood plains had fis-

:;: 55 0 

_J 

w 

aJ 

ALASKA EARTHQUAKE, MARCH 27, 1964 

suring and mudflows as did those 

in the nonpermafrost zone. 

CORDOVA 

Cordova is the only community 

in the uplifted area (fig. 1) that 

has a drilled-well water supply. 

The community is largely built on 

bedrock, but a standby well-water 

supply is located on a thick deposit 

of glacial drift (Walters, 1963, p. 

4) . This small area of unconsolidated material is at least 140 feet 

ft;j w 57 -

u.~ 

~~ - ::J 5cn 

Well Chu 120 

Depth 124ft 

Altitude of land 

surface 350 ft 

f- 0 59 -o::z 

:i:-o:: 

o-' 

fI 61 fc._ 

w 

0 

63 

64 ~~~~~~L-~L-~~~~~_l~_L~_L~~~~~~~L_~ 

Jan. Feb . Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec . Jan. Feb. Mar. 

1964 1965 

20.-Hydrograph of water-level changes in a well in the Chugiak area. 

EXPLANATION 

o 4 

Well 

[l2]] 

Quaternary 

deposits 

Be

~ drock 

undifferentiated 

N 

400 0 400 800 FEET I 

Geology after Wal ters, (1963) 

21.-Sketch map of Cordova showing well locations. 

thick and separates Eyak Lake 

from the ocean (fig. 21). 

There was little visible effect of 

the intense earth shocks at this location only 50 miles from the epicenter, probably because most 

structures are built upon bedrock. 

The ice on Eyak Lake broke and 

some pressure ridges developed 

along the shore. East of Cordova 

on rthe outwash deltas of the glacial 

streams and the Copper River, 

there was extensive fissuring and 

flows (Reimnitz and Marshall, 

1965) and much damage to the 

Copper River h i g h w a y and 

bridges (Kachadoorian, written 

commun. 1966) . The greatest effeet at Cordova was the tectonic 

uplift of about 6 feet, which left 

the city with a useless boat harbor 

(fig. 21) but made some new land 

of an appreciably flatter slope 

than much of the city. 

The Cordova Public Utilities 

manager, Reg Bodington, reported that the earthquake had no 

visible effect on their ground-water supply and facilities. However, possible changes to the unconsolidated material and its relation to sea-water encroachment are 

of major concern because the town 

is only about 20 feet above mean 

sea level (Walters, 1963, p. 8). A 

water sample, collected on July 27, 

1964, from the standby well (Cor 

5, fig. 21), had a chloride content 

of 50 ppm which is an increase of 

10 ppm over the content in samples 

taken in 1962 of wells Cor 4 and 5. 

Only subsequent analyses can determine if the increase is significant. In general, the chances of 

sea-water encroachment are slight 

because Eyak Lake, the probable 

recharge source for the aquifer, 

was raised 6 feet relative to sea 

level and the lake depth was 

unchanged. 

A few water-level measurements 

had been taken in wells Cor 2, 3, 

and 4 in 1961 and 1962, and additional measurements were made in 
EFFE,CTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A21 

July 1964. These measurements 

show that 4 months after the quake 

the water levels were about 1 foot 

higher than in July 1962. Eventually, the water level in the aquifer will probably drop in response to the 6-foot uplift of the 

land. 

The artesian-pressure levels in 

wells 4 and 6, measured July 30'--

31, 1962, fluctuated with tidal loading of the presumed extension of 

the aquifers into Orca Inlet. 

These tide-induced pressures were 

com pared to postearthquake pressure measured in the same wells 

during a comparable tidal cycle on 

July 27-28, 1964. The 1964 measurements showed the artesian-pressure cycle was 6 hours out of phase 

with the tidal cycle-when the tide 

was high the ground-water level 

was low, and vice versa. The 1962 

measurements were not as complete, but they indicate that the 

artesian-pressure cycle lagged only 

about 1 hour behind the tidal cycle. 

The change in the time lag may 

relate to changes in aquifer characteristics, to changes in points of 

tidal loading of the aquifer, or to 

some combination of these and 

other causes unknown. 

Because of the uplift in this 

area, the Eyak River may eventually steepen its gradient back to 

the outlet of Eyak Lake and thus 

lower the lake level, possibly as 

much as 6 feet. 

HOMER 

The effects of the earthquake on 

the aquifers at Homer have been 

described in detail (Waller, 

1966a) ; a summary is presented 

here. To determine the effects of 

the earthquake on the aquifers, 15 

of the wells previously used for an 

observation-well network were remeasured periodically for a year 

after the earthquake. The measurements indicated that both the 

water-table and confined-water 

aquifers in glaciofluvial and Tertiary formations were greatly disturbed, even though Homer is 

about 160 miles from the epicenter. 

However, water levels in all but 

two wells recovered in a few 

months. One well tapping Tertiary rocks (Hom 15, fig. 2) had a 

lowered pressure level of more 

than 8 feet but had recovered 4 feet 

in a yeaes time. The sandstone 

aquifer probably was dilated by 

strain induced by seismic stress. 

If the residual change is permanent, it may be comparable to the 

change in the Anchorage well 

(Anc 1, fig. 19) that also tapsTertiary sandstone. The other well 

(Hom 49, fig. 2) was a shallow 

water-table well which drained 

completely dry in the first few 

months after the earthquake. The 

water level then recovered to its 

former level, but its seasonal fluctuation is now greatly amplified 

over its previous cycle. The aquifer may have been fractured in 

nearby bluffs so that the rate of 

natural discharge is increased 

while seasonal recharge from precipitation is unchanged. 

KENAI LOWLAND 

The Kenai Lowland occupies 

the western part of the Kenai Peninsula (fig. 2) and consists of a 

thick sequence of glaciofluvial deposits overlying Tertiary rocks. 

Ground water occurs in both wa,-

ter-table and confined aquifers, 

and their response to the earthquake is comparable to that at Anchorage. For discussion purposes, 

the Homer area on the southern 

tip of the peninsula is excluded. 

Eight observation wells had 

been measured sporadically in the 

2 years preceding the earthquake 

but none had been measured in the 

preceding 8 months. Although occasional measurements were subsequently resumed in these wells, 

it is difficult to evaluate the longterm effects on the aquifers. 

Nevertheless, the record correlations and hydrogeologic similarities to the Anchorage area suggest 

that the hydrologic effects are also 

comparable. 

Of the eight wells in the Kenai 

Lowland area (fig. 2), the three 

wells tapping artesian aquifers 

had adequate records from which 

to evaluate seismic effects. Each 

well represents an area which is 

discussed separately in the following sections. The water-table 

wells are discussed also, but their 

records show that generally they 

were only slightly affected by the 

quake. 

KENAI AREA 

For the Kenai area, measurements from one well (Ken 17, figs. 

2, 22) indicate that pressure in the 

confined aquifer dropped more 

than 10 feet. The maximum recovery has been only about 9 feet, 

hence the aquifer sustained a longlasting change. Although the 

mineralized water in the aquifer 

suggests that it is a separate aquifer system, the effects probably 

are representative for the Kenai 

area. Measurements in a shallow 

w 

(.) 

<( 

~ 5 

: I 

:510 

3: 

0 

_J 

----?-, 

Well Sol 63 

Depth 100 ft 

Altitude of land 

surface 100 ft 

Soldatna 

~3o~~~~~.rr~~nTnn~~ 

tw \V~:;:,-;;--?--1 Kenai 

J:!:l Depth 163 ft Altitude: 

z 35 of land surface 80 ft 1 ,..-'\ I //\ I 

ci ,/ \ I I \/ 

~ ,/ \ I / < 

<! ./'" - ....... ? ... """" ~ I 

3:40 Well AP 9 I>J o Depth 100ft ,· 

I- Altitude of land \ /\ ~-

I surface 240 ft 1 1 \ 1 

\1:45 I I \ I 

W I J \J 

D ~ ~? 

50UULUUL~JUD~~~~u~~~~~ 

1962 1963 1964 1965 

22.-Hydrographs of three wells in the 

Kenai Lowland showing residual 

changes. 
A22 

water-table well adjacent to Ken 

17 indicated only that the water 

level might be lower than in other 

years. The greater Kenai area 

evidently had more well trouble 

than any of the other areas except 

Valdez. Many wells sanded up, 

probably because the wells are 

commonly finished with preperforated casing in fine to medium 

sand. 

A verified change in chemical 

quality and an increase of temperature of ground water was investigated at the Bernice Lake 

powerplant north of Kenai (fig. 

2). The powerplant has two 174-

foot drilled wells which pump water used for cooling. The standby 

well did not operate after the 

earthquake because it was sanded 

up to about 168 feet from the surface. The pump column was 

pulled in mid-April 1964 and reduced in length 5 feet in order to 

pump water from above the 

sanded-up part. The water was 

yellow and was warmer than it had 

been earlier; one workman reported later that he remarked to 

his coworker at the time that the 

pump column felt warm at about 

the 70-foot level The well was 

pumped for a :few hours and the 

water temperature remained about 

68°F, whereas water from the 

other well200 feet away was 41 °F. 

The temperature of the water from 

both wells was 39,o F at the time of 

drilling in 1962-normal for this 

area. The chemical concentrations 

in the water :from the warmer well 

are shown in the :following table: 

Constituent 

Calcium (Ca) ______ _ 

Magnesium (Mg) ___ _ 

Sodium (Na) ______ _ 

Bicarbonate (HC03) _ 

Carbonate (C03) ___ _ 

Sulfate (804

) ______ _ 

Chloride (Cl) ______ _ 

Hardness as CaC03 __ 

Alkalinity as CaC03-

Total alkalinity as HCOJ ___________ _ 

Parts per million 

1962 1964 

11 48 

1. 3 12 

50 80 

236 151 

0 12 

1 41 

9. 2 99 

33 170 

194 124 

236 151 

ALASKA EARTHQUAKE, MARCH 27, 1964 

The geology and hydrology of 

the site indicate that at about 60-

70 feet a water-table aquifer having a high iron content overlies a 

clay-silt sequence, which acts as a 

confining layer over the 154- to 

17 4-foot aquifer. The pressure 

surface :for the deeper aquifer is 

about 130 :feet below the surface. 

The water-table a q u i :f e r discharges on the sea bluffs about half 

a mile west, and presumably the 

confined aquifer discharges beneath the sea. The water-table 

aquifer was reported "irony" by 

the driller, and discharge points 

along the Kenai bluffs show a distinctive iron-stained precipitate. 

A possible source of the increased temperature of the well 

water is hot water derived from 

the steam discharge of the plant 

blow-down pit, a little more than 

100 feet upgradient from the assumed ground-water flow. The 

plant had been in operation for 

about 6 months, and hot water presumably filtered down to the shallow water and heated it as it 

slowly migrated seaward. The 

intense shaking and water-pressure increases at the time of the 

earthquake probably disrupted the 

confining layer between the two 

aquifers, and allowed hot water 

from the shallow aquifer to flow 

down to the deeper aquifer, probably along the outside of the casing or possibly through disturbed 

parts of the confining layer. To 

test this theory, a dye was put into 

the blow-down pit, but the test 

was inconclusive because the well 

discharge was observed only 1 day, 

whereas the ground-water flow is 

most likely much less than 100 feet 

a day. An alternative explanation would be that the shallowaquifer water seeped through the 

well casing, but the plant officials 

are confident that there is no break 

in the casing. 

Water from the shallow aquifer 

may have been leaking to the lower 

aquifer for a considerable time. 

If so, changes in quality and temperature might never have been 

known if the well had not been 

sanded up by the earthquake. A 

chemical analysis of the shallow 

water is needed to evaluate better 

the quality changes. The well upgradient from the blow -down pit is 

still used. Its water temperature 

in May 1964 was 41°F, 2°F 

warmer than it was in 1962. 

SOLDATNA-STERLING AREA 

The Soldatna-Sterling area is 

east of Kenai and is very similar 

to Kenai in geology and hydrology. Soldatna, located in the 

Kenai River valley, has some flowing artesian wells. Well effects 

were similar to those in other areas 

but, because of the flowing conditions at Soldatna, the pressure 

drop was more noticeable to residents. Many wells in the Sterling 

area were sanded because the wells 

penetrating the fine sand aquifers 

had preperforated casing. 

Sporadic observations in two 

wells near Sterling indicate that 

the water level in the shallow-water-table gravel aquifer may have 

been gradually lowered locally 

owing to increased discharge :from 

springs or outflow along the Kenai 

River banks. One well (Sol 42, 

fig. 2), that had had 3 feet of water, 

was dry by mid-June and was still 

dry in November. 

The plotted hydrograph o:f the 

only observation well at Soldatna 

(Sol 63, figs. 2, 22) shows a drop 

in pressure level of at least 8 feet. 

The drop was possibly several :feet 

more, but an ice cap in the well 

prevented measurements during 

April and May. The fact that the 

peak recovery a year later was 

only 4 :feet implies a change in the 

aquifer. Analogy with geologic 

conditions at Anchora.ge and Kenai suggests that permeability of 
EFFE·CTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A23 

the aquifer may have been increased by removal of fine material, or by dilation of the aquifer 

by the e a r t h q u a k e-imposed 

stresses. An alternative explanation, a change in the discharge 

zone, is difficult to evaluate for the 

following reasons : ( 1) The elevation of the well is only about 100 

feet above sea level, but the depth 

of the well is also 100 feet. (2) 

Moreover, the water level in the 

well is above the level of the adjacent river, so the aquifer is presumably unrelated to this segment of the river. It is reasoned 

that the aquifer extends seaward 

at a gentle gradient and discharges into Cook Inlet, 8 miles 

away. If so, a lowering of water 

level caused by a disturbance in 

the discharge zone should progress inland, as the record of the 

Kenai well (Ken 17) suggests, 

and then the water levels should 

resume a normal seasonal cycle. 

This progression cannot be substantiated because no measurements were made in the well (Sol 

63) during the first 3 months following the quake. 

ANCHOR POINT-KASILOF AREA 

The geologic and hydrologic 

conditions in the area between the 

Kasiloif and Anchor Rivers are 

similar to those in the Kenai Lowland, but the land is generally 

higher toward the south at Anchor 

Point. The shallo·w-water-table 

wells in sand aquifers south of 

Ninilchik were remeasured periodically and no change in water levels was detected. 

The one observation well at Anchor Point (AP 9, figs. 2, 22), 

which taps a sand and gravel artesian aquifer, was greatly affected 

by the seismic shocks. The water 

level dropped at least 12 feet, and 

recovered only 5 feet in a year's 

time. A new seasonal cycle appears to be established for this 

permanent change in pressure 

level. The lower water level probably results from a change in the 

discharge zone. However, water 

loss owing to earthquake damage 

to the well casing may be the 

cause; an obstruction in the well at 

about 50 feet was noted while 

sounding the depth of the well. 

MATANUSKA VALLEY 

The Matanuska Valley in the 

area around Palmer and Wasilla 

(fig. 2) has a geologic and hydrologic environment similar to 

that of Anchorage, but it does not 

have as great a thickness of estuarine clay and silt (Trainer, 1960). 

Trainer established a network of 

observation wells, and 10 of the 

wells have been periodically measured since 1952. All the observation wells were measured a few 

hours or a few days before the 

quake. These measurements, together with knowledge of the areal 

hydrology, made possible a thorough evaluation of the effects of 

the earthquake in this area, some 

10 miles closer to the epicenter than 

Anchorage. 

In the Matanuska Valley, as at 

Anchorage, all power was cut off 

by the earthquake so that wells 

were not pumped for about 20 

hours. Initial reports indicated 

many well failures, but most were 

mechanical failures, chiefly the 

parting of plastic pipe joints. The 

artesian system is not as extensive 

as at Anchorage, so pumping effects do not greatly influence other 

wells. Water-level measurements 

were started on all wells by March 

31, and a lower artesian pressure 

was noted in most. However, 

when the surge of heavy pumping 

stopped, most water levels recovered to normal. Residual effects 

were observed in some wells where 

water levels either rose higher than 

normal or did not recover a pressure loss. 

The hydrographs of four wells 

(fig. 23, next page) illustrate significant changes or residual effects. 

One well (MV 365) illustrates the 

effects of pumping a little-used 

standby well (MV 363b) for the 

city of Palmer for a few days after 

power was restored. Upon cessation of the pumping, the water 

level recovered to its prepumping 

level. However, an abandoned 

city well (MV 363a) closer to the 

standby well than MV 365 showed 

a continued rise and as of March 

1965 appears to have had a permanent rise of water level. This rise 

may not have been due to a widespread aquifer change caused by 

the earthquake. It is more likely 

that some local change occurred to 

improve the recharge area of the 

well. The standby well and MV 

363 have long had peculiar differences of water level that are related to the variations in aquifer 

characteristics, although they both 

tap the same aquifer and are only 

208 feet apart (Trainer, 1960). 

Well MV 445b, adjacent to a 

well that was extensively pumped 

after the earthquake, showed progressive lowering of artesian pressure that may be permanent. Because this well taps a higher confined aquifer than the pumped 

well, and was formerly little affected by its pumping (Trainer, 

1960, p. 51), the postquake lowering of the water level apparently is 

the result of a structure change in 

the aquifer. Trainer (1960, p. 51) 

believes that the upper aquifer recharges the lower one through 

thinner or more permeahle parts 

of generally impermeable till. If 

so, the pressure head of the lower 

aquifer should eventually rise. 

Well MV 185 (fig. 23) shows the 

water-level changes in a deep water-table aquifer. The graph 

shows that there was no change until normal recharge from snowmelt and late summer rains raised 

the water level to 69.58 feet below 

the land surface-a new high in 
A24 

5 

w 0-

u 

~ 

I I I I 

Flowing 

t t t t 

Well MY 445b 

Depth 160ft 

Altitude of land surface 172 ft 

ALASKA EARTHQUAKE, MARCH 27, 1964 

I I I I I I I I I 

t 

C/) ~-31-===~1===1====1======~=1===='======================================================~ 25 ~ 

Cl 

z 

<1: 

_J 

~ 

s 30 w 

co 

Cl 

z 

<1: 

Well MY 365 

Depth 79ft 

Altitude of land surface 365 ft 

~---------------~ -------- ~-- -------------~/-

2i w35'-===========~======================================~====~=====~====~======'===='==='==~ 45 ~ 

f-~ Well MY 363a ------- J 

z ~ 50 Altitude of Depth land 159ft surface 388ft -----------------./ J/ 

c;j ~ ~· ---------------~ 

~ \ _J 

OC55~==='===='======'====1~~~======1====~~~======'===='==~~==~1======1==~1====1======'=======I==~ ~ 66 

~ Well MY 185 

Depth 83 ft 

70 Altitude of land surface 172ft ----

-~--- - j ~---- ~~~ ---

~· ------ -~--~~ ~-~~ 

7 5 [ _ _j___ji_L____l_ I___L__L__ I_:____JI_L____l_ ~~-_L__ l__c_ _ __j____L__L____L__j_,_L_l___ I_J____JIL_j____..l_ l:_j__l___ l_j__ __ IL-::-:-j____j_j_____L_I _j___ '-'--=-'-::'j____j__ I.J__J 

Sept. Oct. Nov. Dec. Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Jan. Feb. Mar. 

1963 1964 1965 

23.-Hydrographs of water-level changes in four wells in the Matanuska Valley. 

the 15 years of record. Records 

through 1960 have been published 

for this 'veil and well MV 365 

(Waller, 1963, p. 8-9). The increased rise in water level presumably resulted from above-normal 

pmcipitation over a period of several months, or possibly from 

changes in the aquifer in the recharge area. 

SEWARD 

Seward is at the head of a 

steep, mountain-walled fiord (fig. 

24) . Most of the town and dock 

facilities lie on an alluvial fan 

built into the fiord by Lowell 

Creek. The creek has been diverted into the city water system 

at the apex of the fan; thus the alluvial fan is probably virtually 

dewatered. North of the business 

district, residential areas are located on the J ap Creek alluvial 

fan which extends onto the Resurrection River valley deposits. 

Along the waterfront, near the 

toe of the alluvial fan, fissures were 

formed behind submarine slides, 

and water and sediment were 

ejected. On the Jap Creek alluvial fan, at the Forest Acres residential area, extensive fissuring 

and flows also developed. 

Lemke (1966) noted the immediate effects on two wells north of 

Seward. One flowing well was so 

damaged that no water is now obtainable, but a nearby nonflowing 

artesian flowed for at neast a week 

immediately after the earthquake. 

Only one well (Sew 8) was located 

on the Lowell Creek alluvial fan. 

The prequake water level is unknown except for the reported 

original level of 66 feet when the 

well was drilled to 78 feet. This 

low water level at the apex of the 

fan and the mouth of the canyon, 

about 123 :feet above sea level, may 

have been due to lack of surfacewater recharge because of the upstream diversion. According to 

Max Lohman, city utilities man 

(oral commun., 1964), the well 

could not be used after the quake 

because water levels were too low. 

Several measurements made between May 10 and August 23, 1964, 

showed that the water level rose 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A25 

from 75.12 to 74.07 feet below the 

land surface. From these measurements it appears that the 78-

foot well lost enough head that 

pumping was not feasible with 

(f) 

z 

<{ 

1--

z 

:J 

0 

N 

only 3 feet of water in the well. 

Whether the water level would 

have recovered eventually will 

never be known because the well 

was deepened to 123 feet in JanAirport 

RESURRECTION 

BAY 

EXPLANATION 

Well 

Base of mountain 

500 

-====- Alluvial fan 

0 500 FEET 

24.-Sketch map of Seward, at the base of Kenai Mountains, showing geomorphology 

and well locations. 

uary 1965. A new water-bearing 

zone, or continuation of the upper zone, was developed near bedrock and the static water level 

on February 5 was reported to be 

96.5 feet. 

Water-level measurements were 

made in wells Sew 5 and 6 on the 

J ap Creek alluvial fan in June 

1961 (Tryck-Nyman and Assoc., 

written commun., 1961) and were 

reported to be a little more than 

18 feet below land surface in each. 

One measurement made in each 

well on May 10, 1964, showed that 

the water level was still about 18 

feet in Sew 5 and rubout 21 feet in 

Sew 6. Subsequent measurements 

could not be made to show any 

trends or to confirm the measurements. However, measurements 

made from July 9 to August 23, 

1964, in the new well adjacent to 

Sew 6 showed that the water level 

lowered from 21.50 to 22.45 feet 

during this time. Hence, the 

water level of this new deep well 

seems to correlate with those of 

the old wells of unknown depth 

and implies that they all tap the 

same aquifer. 

The available evidence suggests 

that aquifers on the J ap Creek 

fan are a complex of alluvialfan deposits and an underlying 

alluvial aquifer deposited by the 

Resurrection River. The wells 

tap the deeper part of the aquifer 

complex. Comparison of water 

levels in the old wells with those 

so far determined in the new wells 

suggests that the earthquake had 

no permanent effects on the 

aquifers. 

Postearthquake drilling of test 

holes on the shore at the head of 

Resurrection Bay (fig. 24) penetrated artesian aquifers having 

sufficient head to flow 10 gallons 

per minute at 6 feet above the surface. A water sample taken August 14, 1964, was analyzed by the 

U.S. Geological Survey. The 
A26 

61° F water had 25 parts per million chloride, a hardness of 98, 

a pH of 8.0, and a specific conductance of 250 micromhos at 25° C. 

This water is probably from an 

aquifer correlative with the deep 

aquifer on the J ap Creek alluvial 

fan. Lemke (1966) believes this 

artesian system helped to reduce 

the stability of the submarine 

slopes that failed nearby during 

the quake. 

VALDEZ 

Valdez was perhaps the most extensively devastated of the larger 

towns affected by the earthquake. 

The overall effects to the community are described by Coulter and 

Migliaccio ( 1966). 

Valdez is near the head of Port 

Valdez (fig. 2) on a glaciofluvial 

outwash delta tha;t drops off steeply underwater into the fiord. The 

silt, sand, and gravel deposits of 

Alaska's water resources were 

visibly and invisibly subjected to 

tremendous forces during the 

earthquake. The greatest hydrologic effects were confined to areas 

of thick unconsolidated deposits 

within a radius of about 200 miles 

from the epicenter. Effects probably were lessened because the 

event occurred in late winter, before spring thaws began, when 

water levels were at their annual 

low and depth of frozen ground at 

its seasonal maximum. 

Immediate effects were generated by the seismic waves. The 

ground or surface waves caus.ed 

noticeable oscillations and turbidity of water in lakes, rivers, and 

shallow ground water 450 miles 

from the epicenter. The compressional waves, acting on confined 

water, caused eruptions of sediment-laden water in most of the 

ALASKA EARTHQUAKE, MARCH 27, 1964 

the delta are saturated with water 

to within 10 feet of the relatively 

fiat land surface. As best as can 

be determined from the few subsurface data, the water-bearing 

formations are not confined. Numerous home owners had driven 

wells to reach the shallow water 

table. The city had two wells 

about 60 feet deep. Water levels 

stood about 4 feet below land surface when these wells were drilled 

in 1954. 

Many first-hand reports of residents indicate the tremendous effects of the earth motion on the 

ground and on the shallow aquifer. Basements were filled with 

silty water gushing in through 

floor drains or cracks. Water and 

sediment were ejected from cracks 

that opened in the streets. Elsewhere some 5 feet of snow masked 

many of the cracks. Water and 

SUMMARY 

alluvial areas within 100 miles of 

the epicenter and increased the turbidity of artesian wells. Artesian 

water levels fluctuated as much as 

24 feet in one area. 

The seismic shock or stresses 

imposed by the earthquake caused 

changes in many aquifers that may 

be permanent. As a result of these 

aquifer changes, water levels were 

lowered and some are apparently 

not recovering to their former 

height. 

Long-term changes in the hydrologic regimen are being 

brought about by rearrangement 

of granular material, subsidence or 

elevation of landmasses, land 

slides, and the formation of rock 

fractures and fissures. As a result, ground water is establishing 

new flow patterns, lakes are establishing new levels, and streams are 

sewer lines were broken in numerous places, and streets were 

flooded in places by the outflow of 

water. Sea water, in successive 

waves, was mixed with the ejected 

ground water and with the eruptions from sewerage and water 

mains in the streets and from the 

channels formed by the fissuring. 

A water-level measurement 

made on one well in town on May 

3, 1964, showed that the water table 

was 6 feet below the surface. This 

figure probably represents the approximate low level for the year. 

The unused city well had a water 

level of 10.39 feet on May 3, 1964, 

but the water level was undoubtedly lowered somewhat by an adjacent pumping well. Lack of preand post-quake water-level data 

makes it impossible to determine 

the long-term effects on the 

aquifer. 

establishing new gradients and are 

either aggrading in subsided areas 

or eroding in uplifted areas. 

The long-term effects on ground 

water are the most important because these changes may affect the 

yield of aquifers and may eventually cause deterioration of the 

quality of the water. 

A quotation of an early, perhaps 

the first, scientific earthquake 

writer (Oldham, 1883, p. 60) is an 

appropriate epilogue: 

Vast, however, as these effects appear, they are in reality insignificant, 

mere scratches in the paint of the earth 

in whose history they will leave no 

permanent record. Hundreds of acres 

of land may be broken up, thousands 

of tons of earth may be precipitated 

into the river, and for days and weeks, 

or even months, the stream may boil 

and foam through the wreck, carrying 

ton after ton of earth away in its turbid stream, but only to be deposited 
EFFECTS ON HYDROLOGY OF SOUTH CENTRAL ALASKA A27 

once more lower down, or even in its 

ultimate destination, the sea. Time 

however, will put an end to all this 

disturbance; soon the river course will 

Alaska Department of Fish and Game, 

1965, Post-earthquake fisheries 

evaluation; an interim report on 

the ~larch 1964 earthquake effects 

on Alaska's fishery resources: Juneau, Alaska, 72 p. 

Cederstrom, D. J., 'l'rainer, F. W., and 

Waller R. M., 1964, Geology and 

ground-water resources of the Anchorage area, Alaska: U.S. Geol. 

Survey Water-Supply Paper 1773, 

108 p. 

Coulter, and :Vligliaccio H. W., 1966, 

Effect'S of the earthquake of ~larch 

27, 1964, at Valdez, Alaska: U.S. 

Geol. Suney Prof. Paper 542-C, 

3U p. 

Davis, T. N., 1960, A field report on the 

Alaska t>arthquakes of April 7, 

1958: Seismol, Soc. America Bull., 

v. 60, no. 4, p. 489-510. 

Donn, vV. L., 1964, Alaskan earthquake 

of 27 l\Iarch 1964-remote seiche 

stimulation: Science, v. 145, no. 

3629, p. 261-262. 

Ferrians, 0 .. J ... Jr., 1966, Effects of the 

earthquake of March 27, 1964, in 

the Copper River basin: U.S. Geo'l. 

Survt>y Prof. Paper 542-C. (In 

press.) 

Ferris, J. G., Knowles, D. B., Brown, 

R. H., and Stallman, R. W., 1962, 

Theory of aquifer tests: U.S. Geol. 

Survey Water-Supply Paper 1536-

E, p. 69-174. 

Grantz, Arthur, Plafker, George, and 

Kachadoorian, Reuben, 1964, Alaska's Good Friday earthquake, 

March 27, 1964-a preliminary geologic evaluation: U.S. Geol. Survey Circ. 491, 35 p. 

Hansen, W. R., 1966, Investigations of 

the U.S. Geological Survey, in The 

Alaska earthquake, Mareh 27, 

1964-Field investigations and reconstruction effort: U.S. Geol. Survey Prof. Paper 541. (In press.) 

.Johnson Drillers .Journal, The 1964 

Parthquake proves value of well 

water system: The Johnson Drillbe cleared and once more the river 

will flow as placidly as ever; wind and 

rain will break down the sharp, edges 

of the overturned masses, will fill up 

REFERENCES CITED 

ers Jour., July-August, v. 36, no. 

4, p. 4-5. 

Kachadoorian, Reuben, 1964, Effects 

of Alaska's Good Friday earthquake on land [abs.]: Am. Geophys. 

Union Trans., v. 45, no. 4, p. 634. 

Lemke, R. W., 1965, Engineering geologic effects of the ::\larch 27, 1964, 

earthquake at Seward, Alaska 

[abs.] : Geol. Soc. America Spec. 

Paper 82, p. 121. 

Lemke, R. W., 1966, Effeets of the 

earthquake of March 27, 1964, at 

Seward, Alaska: U.S. Geol. Survey 

Prof. Paper 542-E. (In press.) 

McCulloch, David, 1966, Slide-induced 

waves, seiching and ground fracturing caused by the earthquake of 

March 27, 1964, at Kena'i Lake, 

Alaska: U.S. Geol. Survey Prof. 

Paper 543-A. (In press.) 

McGarr, Arthur, 1965, Excitation of 

seiches in channels by seismic 

waves: Jour. Geophys. Research, v. 

70,no.4,p.847-854. 

Miller, W. D., and Reddell, D. L., 1964 

Alaskan earthquake damages Texas 

High Plains water wells: Am. 

Geophys. Union Trans., v. 45, no. 

4, p. 659-663. 

Oldham, Thomas, ed., 1882, The Gachar 

earthquake of 10 January 1869: India Geol. Survey Mem., v. 19, art. 

1, 98p. 

Pewe, T. L., 1964, Good Friday earthquake, Alaska : GeoTimes, v. 8, no. 

8, p. 9-10,22-23. 

Plafker, George, 1965, Tectonic deformation associated with the 1964 

Alaska earthquake: Science, v. 148, 

no.3678,p. 1675-1687. 

Press, Frank, and Jackson, David, 

1965, Alaskan earthquake, 27 

March 1964-Vertical extent of 

faulting and elastic strain energy 

release: Science, v. 147, no. 3660, 

p. 867-868. 

Ragle, R. H., Sater, J. E., and Field, 

W. 0., 1965, Effects of the 1964 

Alaskan earthquake on glaciers 

and related features: Arctic Inst. 

the cracks and holes, and in a few 

years at most the surface will be smooth 

and as luxuriantly clad with vegetation 

as ever it was before the catastrophe. 

North America, Research Paper 

32, 44p. 

Reimnitz, Erk, and Marshall, N. F., 

1965, Effects of the Alaska earthquake and tsunami on recent deltaic sediments: Jour. Geophys. Re· 

search, v. 70, no. 10, p. 2363-2376. 

Trainer, F. W., 1960, Geology and 

ground-water resources of the Matanuska Valley agricultural area, 

Alaska: U.S. Geol. Survey WaterSupply Paper 1494, 116 p. 

Tuthill, S. J., Laird, W. M., and Freers, 

T. F., 1964, Geomorphic effects of 

the Good Friday (March 27, 1964) 

earthquake in the Martin River and 

Bering River area, south-central 

Alaska [rubs.] : Geol. Soc. America 

Spec. Paper 82, p. 209. 

U.S. Coast and Geodetic Survey, 1964, 

Prince William Sound, Alaskan 

earthquakes, Mareh-April 1964: 

U.S. Coast and Geod. Survey, Seis· 

mology Div. Prelim. Rept., 83 p. 

Vorhis, R. C., 1966, Hydrologic effeets 

of the March 27, 1964, earthquake 

outside Alaska: U.S. Geol. Survey 

Prof. Paper 544-C. (In pres'S.) 

Waller, R. lVI., 1960, Data on water 

wells and springs in the Chugiak 

area, Alaska : Alaska Dept. Health, 

Sanitation and Eng. Sec., Water 

Hydrolog. Data 10, 28 p. 

--- 1963, Alaska, in Hackett, 0. M., 

Ground-water levels in the United 

States, 1959-60, Northwestern 

States: U.S. Geol. Survey WaterSupply Paper 1760, p. 3-12. 

--- 1964, Hydrology and the effects 

of increased ground-water pumping in the Anchorage area, Alaska : 

U.S. Geol. Survey Water-Supply 

Paper 1779-D, 36 p. 

--- 1966a, Effects of the earthquake 

of :\larch 27, 1964, in the Homer 

area, Alaska: U.S. Geol. Survey 

Prof. Paper 542-D. (In press.) 

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earthquake on the hydrology of the 

Anchorage area, Alaska: U.S. Geol. 

Survt>y Prof. Paper 544-B. (In 

press.) 
A28 

Waller, R. M., Thomas, H. E., and Vorhis, R. C., 1965, Effects of the Good 

Friday earthquake on water sup• 

plies: Am. Water Works Assoc. 

Jour., v. 57, no. 2, p. 123-131. 

ALASKA EARTHQUAKE, MARCH 27, 1964 

Walters, K. L., 1963, Geologic reconnaissance and test-well drilling, 

Cordova, Alaska: U.S. Geol. Survey Water-Supply Paper 1779-A, 

llp. 

Wigen, S. 0., and White, W. R. H., 1964, 

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U.S. GOVERNMENT PRINTING OFFICE.t966 0-209-981 
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