Listed below are the currently available Drainage Basin Codes in GWIC.

Basin HUC Description
AA 10020001 RED ROCK RIVER
AB 10020002 BEAVERHEAD RIVER
AC 10020003 RUBY RIVER
AD 10020004 BIG HOLE RIVER
AE 10020005 JEFFERSON RIVER
AF 10020006 BOULDER RIVER
AG 10020007 MADISON RIVER
AH 10020008 GALLATIN RIVER
BA 10030101 MISSOURI RIVER BETWEEN LITTLE PRICKLY PEAR CREEK AND THREE FORKS
BB 10030102 MISSOURI RIVER BETWEEN MARIAS RIVER AND LITTLE PRICKLY PEAR CREEK
BC 10030103 SMITH RIVER
BD 10030104 SUN RIVER
BE 10030105 BELT CREEK
CA 10030201 TWO MEDICINE RIVER
CB 10030202 CUTBANK CREEK
CC 10030203 MARIAS RIVER
CD 10030204 WILLOW CREEK OF THE MARIAS RIVER
CE 10030205 TETON RIVER
DA 10040101 MISSOURI RIVER BETWEEN BULLWHACKER CREEK AND MARIAS RIVER
DB 10040102 ARROW CREEK
DC 10040103 JUDITH RIVER
DD 10040104 MISSOURI RIVER BTWN FT PECK DAM AND BULLWHACKER CK
DE 10040105 BIG DRY CREEK
DF 10040106 LITTLE DRY CREEK
EA 10040201 MUSSELSHELL RIVER ABOVE HALFBREED CREEK
EB 10040202 MUSSELSHELL RIVER BTWN FLATWILLOW CK AND HALFBREED CK
EC 10040203 FLATWILLOW CREEK
ED 10040204 BOX ELDER CREEK
EE 10040205 MUSSELSHELL RIVER BELOW FLATWILLOW CREEK
FA 10050001 MILK RIVER ABOVE RED RIVER OF THE MILK RIVER
FB 10050002 MILK RIVER BTWN FRESNO DAM AND RED RIVER OF THE MILK RIVER
FC 10050003 WILDHORSE LAKE INTERNAL DRAINAGE
FD 10050004 MILK RIVER BETWEEN WHITEWATER CREEK AND FRESNO DAM
FE 10050005 BIG SANDY CREEK
FF 10050006 SAGE CREEK OF THE MILK RIVER
FG 10050007 LODGE CREEK
FH 10050008 BATTLE CREEK
FI 10050009 PEOPLES CREEK
FJ 10050010 COTTONWOOD CREEK OF THE MILK RIVER
FK 10050011 WHITEWATER CREEK
FL 10050012 MILK RIVER BELOW WHITEWATER CREEK
FM 10050013 FRENCHMAN CREEK
FN 10050014 BEAVER CREEK OF THE MILK RIVER
FO 10050015 ROCK CREEK OF THE MILK RIVER
FP 10050016 PORCUPINE CREEK OF THE MILK RIVER
GA 10060001 MISSOURI RIVER BETWEEN POPLAR RIVER AND FT PECK DAM
GB 10060002 REDWATER RIVER
GC 10060003 POPLAR RIVER
GD 10060004 WEST FORK POPLAR RIVER
GE 10060005 MISSOURI RIVER BTWN YELLOWSTONE RIVER AND POPLAR RIVER
GF 10060006 BIG MUDDY CREEK
GG 10060007 GOOSE LAKE INTERNAL DRAINAGE
HA 10070001 YELLOWSTONE RIVER ABOVE REESE CREEK
HB 10070002 YELLOWSTONE RIVER BTWN BRIDGER CK AND REESE CK
HC 10070003 SHIELDS RIVER
HD 10070004 YELLOWSTONE RIVER BTWN ALKALI CK AND BRIDGER CK
HE 10070005 STILLWATER RIVER OF THE YELLOWSTONE RIVER
HF 10070006 CLARK FORK OF THE YELLOWSTONE RIVER
HG 10070007 YELLOWSTONE RIVER BTWN BIGHORN RIVER AND ALKALI CK
HH 10070008 PRYOR CREEK
IJ 10080010 BIGHORN RIVER BTWN YELLOWTAIL DAM AND SAGE CK
IN 10080014 SAGE CREEK OF THE BIGHORN RIVER
IO 10080015 BIGHORN RIVER BELOW YELLOWTAIL DAM
IP 10080016 LITTLE BIGHORN RIVER
JA 10090101 TONGUE RIVER ABOVE AND INCLUDING HANGING WOMAN CK
JB 10090102 TONGUE RIVER BELOW HANGING WOMAN CREEK
KG 10090207 POWDER RIVER ABOVE LITTLE POWDER RIVER
KH 10090208 LITTLE POWDER RIVER
KI 10090209 POWDER RIVER BELOW LITTLE POWDER RIVER
KJ 10090210 MIZPAH CREEK
LA 10100001 YELLOWSTONE RIVER BTWN POWDER RIVER AND BIGHORN RIVER
LB 10100002 BIG PORCUPINE CREEK OF THE YELLOWSTONE RIVER
LC 10100003 ROSEBUD CREEK OF THE YELLOWSTONE RIVER
LD 10100004 YELLOWSTONE RIVER BELOW POWDER RIVER
LE 10100005 O'FALLON CREEK
MA 10110201 LITTLE BEAVER CREEK OF THE LITTLE MISSOURI RIVER
MB 10110202 BOX ELDER CREEK OF THE LITTLE MISSOURI RIVER
MC 10110203 CANNONBALL CREEK
MD 10110204 BEAVER CREEK OF THE LITTLE MISSOURI RIVER
NB 10120202 BELLE FOURCHE RIVER
OA 17010101 KOOTENAI RIVER
OB 17010102 FISHER CREEK
OC 17010103 YAAK RIVER
OD 17010104 KOOTENAI RIVER BELOW YAAK RIVER
OE 17010105 MOYIE RIVER OF THE KOOTENAI RIVER
PA 17010201 CLARK FORK RIVER ABOVE BLACKFOOT RIVER
PB 17010202 ROCK CREEK AND FLINT CREEK DRAINAGES
PC 17010203 BLACKFOOT RIVER
PD 17010204 CLARK FORK RIVER BTWN FLATHEAD RIVER AND BLACKFOOT RIVER
PE 17010205 BITTERROOT RIVER
PF 17010206 NORTH FORK FLATHEAD RIVER
PG 17010207 MIDDLE FORK FLATHEAD RIVER
PH 17010208 FLATHEAD RIVER BTWN KERR DAM AND N FORK FLATHEAD RIVER
PI 17010209 SOUTH FORK FLATHEAD RIVER
PJ 17010210 STILLWATER RIVER OF THE FLATHEAD RIVER
PK 17010211 SWAN RIVER
PL 17010212 FLATHEAD RIVER BELOW FLATHEAD LAKE
PM 17010213 CLARK FORK RIVER BELOW FLATHEAD RIVER
QA 09040002 BELLY RIVER
QB 09040001 ST MARYS RIVER
UNABLE UNABLE TO DETERMINE