Upload
others
View
1
Download
0
Embed Size (px)
Citation preview
NiaO
4'0oe
cs.
cv
cc"ct FL'
111111111111111r 1110111METRO/NORTHWEST 2M
-,, E E .E -.-' . 4-I . co
a) .0 c.) .0 '-' 0cu cn 0 0 a) -0 --I.+ </)
t-i' CO -.-..-Ioy
\., 13 toca 7\_.‘" a>a)Qalmcz=
%I= -8 " S "8 E . , 9. 2 i°24 - , ..,E. ' i i iw .r‘/,?. ci '2'7; .4: i ii ,L;
8 E 8 gs, -a, zGOO C.T.,
0 =CD f.., .-1 CO
W C) $. t -t$ 8 ^0 -t-A a)c,.., c■-■ 0 "0 t:1■;--. = (TS 0 ,--, ci, cz ,.0 ,, 0 ''' 72. 0 0 ^0 (1) 0.0 a) :0 -0s'008C)Ecc$0 al s.., C:, taA vi••-"Cl .4"-' ;5' ''' 4-.CD Ct-.-' a.) CI) X
r0 CZ 6:24 cq- "Cg A.tz. a) >,,,L, -■-• -as . • z . ..cs -)--. ,,,,g a) ert7'7 c1) ,-. 0-0Q0a> '000°0-:::u)a) '4 .4 - ci) 0,- .-6 : 0 as . -. : ,„ ;._. (,) : . ..,.,
VD 1= , .CD ,2 > 0, OD
>2 ,zCtS z'.... ,,DZ 'C ■• S C-- °
4-,,, TA 0 ;--. g a> a) 5L).... 2 la up Ci) acs.
CD ta.0 Ci) a) .,,c2, 4
w>ct ' ,s4:1! .,. i :: L.. .,ti . . • _ .. 0:- ° c. qi - :, ;
s. o s.., 03 s-, 4
3. CD ca Z C.) -4-,cn ;,_, vs a) •.-■ .-, •••• ,,,-
0 S. c..) -.-' c.-. °
.° . CD ,. cNS cO $4 $-• > -
..--. •,1 • 1. Cr3 •C •I.
CZ ;•.1 > CZ = .''''
Cn 0 0 .^. >
, •,-, ..... -....
cn v._, 0 t:,011,_,""7, i s.110-44110,vA49.0
A 11
, ,.. ,c$ , ,... cz.-- .,1) . -- z (..) v' 1.yr,). -' pp -.) s.
( g @,,,,,,,,e
.„ _ = ,A mc.I cu .-,co a 2
toE g
GC
,_
N.,,, . z c„ ,,,..-
:3, cs' E .1 .1) :: g, f : ,9 I 1 :
- 0 . -,,,i r-+. „,^ r̂ a) ,, 0N-. CD •,-■ ^ cz 0 L 0
C, CI CCS 0 nz$ ›, 0(0 -ty.) = 0 $.4 ,.., S., .,..,CC "0 CI) = 1.7.
c, ._0_,(1) >a) g -Ft c.,51", cn CI
CD
$ ecscii" was 2 g g = ) '',n 4
E V `n X67 r-+ '''
7.. -.::: „t,, 4 .0 z0 .0 0
- c' >> - u, u
-.4 a; -,-
,W, H
- E = cu 0 0 0 -, z x
. 0 ci.) a) ;_0 --, $-■ - 0 0 a) ca
0
,..
4 0
,f, .0
:
.0 0 cz 0, *0 "0 - ,...
s.., co ”01 ›) •••• ri on M
1:;$ ..... 0 '0 -."'
4-4 64 0 °I.. .,., 0 0 .,..■ •,.. ..-
0 "C1 CD ,-. ,. cts ° t 00 0 =,naLS, 10 CCS .-.c.,,c.) .0 0 +,0 'u Cl.) +-. .45, cip
›,. 00 "Cj 17-1 Lriz) ,,,;..,› 0 z0.100.) ° 17; 3 Z s,=,, • " e>
7; iza ° ma .! !,.E5.6. ,, , ,c 9 , ,,.3 - , , ,1 .; ,, , , ,,.,,Y> ;8- -
„0 ,.. , -,7,; 0 ,.= F., .b, = „ ..., , - -, CD Ca
-4--■ ct a,) 0) E ,,, '-- -S.
° .17 -,--,
S-■ CU 0
Od CI) 0)
C / 3 , 8. al r . 0 c zu 0 ,, ; 3 ,.; - - I.: 0 g) c uS -, , z0 ' . . 1 a ' ' -'› , g w at. -E 8 o cuc" 4- -c=, etz • z to a) ci) .crsa> .$4 ,,,...) 5 : . C .7 : 4 - J : C . 3 .:4" " . . :MC " ) pin . ! =74 7.: 1 c wECt , . . ., _ _ ,. ;5) =c2 i, ,ici, t-„. -6 c..) 6-. ,,,...- .,,,, _c,„ g.,., „,,... g-1-... .,,,,--, 7.---. I c:,ci) ,c=s- ›.,>- ,L- 7t --; .,.. = „, c„.,,,.,,,, .= ,„,, C.)
0 ,_,
C.) -- OD +, "0 " cu cuc) ai 0 t) M 0 .. _ c1') 7'1 .. '-= c...,.. 7 a> s, --,ozs ...-e, u= .5 c/) 1::) zs c., •••• = as a> ,t -)-.) crs 2 a) ›, cz s. 0 = •
CU Z
>
•
fa4 =a) Ma . 2cn tCU IV; .C2Z .T.-4° G.L1 ra al t ."'EW 75 ..., 7.5-4C) = * C1.7 > Ea' .5$1 CUMIci5 GC1- CIA ",-,W •.-'(2) •:Z 7)a) 1 . ) 0 . )' - ' in F''. - t : $. Lt! c. „). st 9 .e? ' - - -= r. .,$ -9- I.t , ncc
';!) .4. -67 j:) +,: • , -7; . :. 1-2 , - -. E ia> -9, -LI ° F C Z -a c) = 3 2 '-'cl) . .5 5, . . .. - ' C / D. - " . 5 49 "C.-. 2 c9 '-'cn cC$' ...-q 2 48 " FL ) - r-O 4 trtt '-' - 5 QJ 4 --' . 1.) 7:5 -.- ---t cz - "° 6T-4 -
0 a)
b-
a)(s)R 0asa3
0
1 I 1 I 1111 75s 0 ,a1.),. _
I4CI) -4.,
.73
11111rA9
rirTH OREGONIAN, SATURDAY, FEBRUARY 24, 1996
Logging: Environmentalists seek federal study of harvests■Continued from Page Oneeral Accounting Office investigationof the role that timber harvestsmight have played in flood damage.
A review of forestry studies -and interviews with forest hydrolo-gists, geologists, road builders andother experts - confirms that evenwithout any logging the Februarystorm still would have created wide-spread damage. Indeed, some forest-ed areas, such as the Salmonberrydrainage of the Tillamook State For-est, appeared in a recent helicopterfly-over to suffer more slides thannearby areas logged by StimsonLumber Co.
But the studies and experts alsoindicate it's too simplistic to put allthe blame on the storm. In someareas, acts of people - particularlyroad building - helped along thisact of nature.
The biggest risks involve building
roads on land that, due to its geolo-gy, is inherently unstable.
"That's the lesson we've learnedfrom the '96 flood, and we havethose unstable areas mapped andthere's no reason to make the samemistake a second time," said JackGerstkemper, a Mount Hood roadengineer.
The aerial survey counted 91slides in clear-cut areas, 93 in road-ed areas and only 59 in forestedareas. The origins of another 11slides could not be determined.
The survey findings reflectearlier, and more thorough, studies.
A 1975 study by Fred Swanson, aForest Service resource geologist,looked at timber harvests in a feder-al forest watershed east of Eugene.Swanson found that the combinedeffects of logging and road-building"appear to have increased slide ac-tivity on road and clear-cut sites by
about five times relative to forestedareas over a period of about 20years."
A 1984 study by G.W. Brown, nowthe forestry dean at Oregon StateUniversity, found that logging androading of steep Coast Range land"increase the frequency and de-structiveness of landsliding. Slidesin clear-cuts move further and causemore damage than those in uncuttimber."
Studies document sedimentationSeveral studies also have docu-
mented increased sedimentationrates from heavily logged areas.That possibility troubles SalemMayor Roger Gertenrich who is try-ing to restore the city's drinkingwater system.
The water flows from Detroit Res-ervoir, which received a huge slugof sediments following the Februarystorm. He fears that the sediment
problem might have been intensifi-ed by logging in some of the water-shed drainages.
"Fundamentally, the people of Or-egon know, and you'd have to bevery dense not to see the relation-ship between logging, roads and tur-bidity," Gertenrich said.
In an effort to reduce the risks oflogging, the past quarter-centuryhas seen a kind of forest revolutionwith a variety of new techniquesused by federal, state, and private-land loggers. Roads are better sur-faced and often routed along ridge-tops rather than winding their wayup erosion-prone mountain faces.Excavated earth is hauled awayrather than dumped off the sides offresh-cut roads.
For the new roads, the stormswere an acid test. And many appearto be doing pretty well.
"What we found in our aerial re-connaissance is that our newer con-
struction is what stayed on themountain," said Gerstkemper, theMount Hood road engineer.
On public lands, the intensity oflogging alst is on decline. Currentannual harvest levels have droppedby 80 percent compared with the'80s, according to Swanson, the For-est Service geologist. Where loggingdoes occur, new techniques avoidthe gouges that used to come fromdragging cut timber uphill to stag-ing areas.
Old roads troublesomeBut the Forest Service, as well as
state and private land managers, isstill stuck with the legacy of pastdecades of logging. The biggest trou-ble spots are the miles of old roads,many of which don't meet currentstandards. These roads still need tobe maintained because plugged cul-verts and eroding roads can actuallytrigger slides and washouts in bigstorms.
Most of those roads are the re-sponsibility of the Forest Service.The agency is trying to shut downsome roads and keep up the rest.But that all costs money, and that'sharder and harder to come by.
The Forest Service road mainte-nance budget for Washington andOregon has declined from $71.2 mil-lion in fiscal year 1985 to only $22million in fiscal year 1995. "That'sjust about half of what we need toadequately maintain our currentroad system," said Gail Aschenbren-ner, a Forest Service spokeswoman.
Poor maintenace might even haveintensified some of the damagewrought by the storm.
"We just can't get to every singleculvert. No way," said Deigh Bates,a Willamette National Forest hy-drologist.
Peter D. Sleeth of The Oregonianstaff contributed to this report.