ARKANSAS RIVER BASIN

07097000 ARKANSAS RIVER AT PORTLAND, CO-Continued

WATER-QUALITY RECORDS

PERIOD OF RECORD.--September 1970 to September 1971, October 1975 to current year. For a complete listing of historical data available for this site, see http://waterdata.usgs.gov/co/nwis/inventory/?site_no=07097000

PERIOD OF DAILY RECORD.--

SPECIFIC CONDUCTANCE: October 1979 to September 1982, observer once-daily measurements; November 1982 to current year.

WATER TEMPERATURE: October 1979 to September 1982, observer once-daily measurements; November 1982 to current year.

INSTRUMENTATION.--Water-quality monitor since November 1982, with satellite telemetry.

REMARKS.--Daily specific-conductance records are good. Daily water-temperature records are good. Daily data that are not published are either missing or of unacceptable quality. Reported values for specific conductance may not be representative of the stream during flash floods. Periodic water-quality data available, Feb. 1977 to Sept. 1995, under National Stream-Quality Accounting Network (NASQAN) for this site.

EXTREMES FOR PERIOD OF DAILY RECORD.--

SPECIFIC CONDUCTANCE: Maximum, 1,650 microsiemens/cm, Aug. 9, 2003; minimum, 111 microsiemens/cm, June 22, 1984 (minimum daily mean).

WATER TEMPERATURE: Maximum, 29.5°C, July 15, 2002; minimum, 0.0°C, on many days.

EXTREMES FOR CURRENT YEAR.--

SPECIFIC CONDUCTANCE: Maximum, 1,650 microsiemens/cm, Aug. 9; minimum, 130 microsiemens/cm, June 1.

WATER TEMPERATURE: Maximum, 26.4°C, July 25, Aug. 4; minimum, 0.0°C, on many days.

Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius 

WATER YEAR OCTOBER 2002 TO SEPTEMBER 2003

DAY	MAX	MIN	MEAN	MAX	MIN	MEAN	MAX	MIN	MEAN	MAX	MIN	MEAN
	OCTOBER			NOVEMBER			DECEMBER			JANUARY
1	597	555	576	515	480	494	497	456	481	---	---	---
2	585	526	557	500	466	479	492	451	477	---	---	---
3	533	493	516	500	462	478	485	454	471	473	458	467
4	506	477	489	486	458	473	490	450	467	462	436	452
5	509	473	486	522	467	487	494	462	478	461	414	438
6	525	476	500	521	474	490	488	459	477	446	411	424
7	524	483	506	526	440	483	---	---	---	444	402	425
8	567	508	526	489	420	465	---	---	---	461	413	433
9	587	524	548	496	439	476	971	440	515	488	433	449
10	555	501	532	494	437	468	489	445	467	490	423	458
11	614	521	564	487	438	462	525	439	471	491	407	462
12	613	548	595	500	446	468	526	477	500	491	437	463
13	611	507	584	512	455	487	512	464	488	500	442	463
14	634	589	613	512	437	488	503	461	477	467	441	454
15	652	584	630	516	468	486	494	458	472	470	448	458
16	659	602	635	516	456	484	484	447	466	498	421	455
17	664	558	642	520	463	490	471	457	465	529	449	483
18	637	562	601	526	470	498	476	453	463	529	474	498
19	638	553	597	519	470	498	481	455	468	565	461	497
20	601	548	585	530	473	499	530	465	488	552	460	487
21	599	548	573	517	480	504	532	485	505	548	438	473
22	627	535	583	---	---	---	535	463	491	494	440	457
23	595	521	549	---	---	---	796	496	527	483	441	463
24	---	---	---	---	---	---	520	472	495	518	431	475
25	525	499	513	---	---	---	500	468	482	510	461	488
26	533	497	515	500	473	485	517	486	495	537	461	483
27	551	491	517	517	462	489	538	504	518	537	469	492
28	544	505	526	515	484	499	537	496	509	502	462	483
29	541	520	529	515	477	494	498	464	478	508	453	475
30	523	499	512	515	473	488	475	430	456	491	437	472
31	507	478	492	---	---	---	---	---	---	484	442	464
MONTH	---	---	---	---	---	---	---	---	---	---	---	---
	FEBRUARY			MARCH			APRIL			MAY
1	485	442	467	514	454	472	552	484	519	572	479	508
2	482	441	461	533	460	481	512	474	493	613	526	562
3	468	444	455	532	428	493	514	439	463	668	543	600
4	468	432	453	521	443	496	468	431	457	632	526	594
5	472	451	461	504	457	482	445	422	434	634	581	606
6	482	445	459	518	464	485	456	426	440	659	569	612
7	548	451	481	519	468	488	467	425	450	650	574	601
8	556	474	521	499	466	484	456	444	450	629	594	611
9	---	---	---	504	465	480	463	427	451	698	603	650
10	---	---	---	498	471	484	479	440	455	663	544	624
11	546	468	494	502	469	485	499	460	475	652	590	621
12	516	448	478	502	482	490	488	461	474	651	604	624
13	498	431	464	508	481	494	532	454	477	674	615	639
14	473	410	437	515	485	499	475	437	457	673	585	625
15	449	421	436	547	468	510	492	465	476	653	548	613
16	477	436	451	527	492	505	465	418	443	600	496	535
17	500	452	465	527	453	495	511	434	459	520	466	479
18	502	461	475	668	492	585	579	488	523	474	418	452
19	491	437	465	659	514	558	581	493	531	418	339	389
20	499	464	482	631	554	585	587	506	544	341	283	311
21	509	474	491	601	532	555	615	533	563	307	280	291
22	521	455	493	591	497	556	589	556	570	330	297	308
23	513	458	481	560	522	540	613	538	566	317	285	299
24	486	463	475	615	503	532	557	513	524	647	253	327
25	523	466	490	574	492	530	565	523	541	335	225	255
26	521	454	470	566	502	521	587	532	563	229	215	223
27	513	446	470	551	480	522	569	539	549	230	199	217
28	517	457	476	530	508	520	586	514	551	200	171	185
29	---	---	---	528	510	520	575	488	520	178	163	170
30	---	---	---	536	509	521	521	468	490	256	152	166
31	---	---	---	529	475	511	---	---	---	160	145	152
MONTH	---	---	---	668	428	512	615	418	497	698	145	447
	JUNE			JULY			AUGUST			SEPTEMBER
1	148	130	143	295	269	283	339	319	331	522	477	503
2	146	137	142	271	261	267	337	318	329	533	482	505
3	148	137	142	277	262	270	343	324	332	787	462	511
4	---	---	---	277	265	273	340	327	331	511	457	479
5	175	150	161	278	264	273	339	327	333	477	460	468
6	179	167	175	292	271	282	364	337	352	485	343	459
7	198	178	187	309	288	298	368	342	354	493	371	464
8	224	198	211	311	287	297	356	335	342	466	425	444
9	242	217	226	299	278	291	1,650	335	422	439	411	424
10	431	209	236	307	290	298	451	322	354	440	417	428
11	224	191	201	308	295	303	332	300	313	417	381	397
12	193	159	181	316	303	312	333	294	314	395	368	380
13	178	153	170	321	306	317	355	310	326	391	371	380
14	176	170	173	320	303	315	378	355	360	389	373	380
15	---	---	---	543	295	340	404	376	393	400	369	384
16	---	---	---	393	328	351	411	384	400	410	377	389
17	357	169	188	344	313	328	---	---	---	453	399	417
18	264	177	198	341	327	332	480	446	464	469	422	437
19	893	222	280	332	320	326	483	436	456	468	422	440
20	304	225	252	336	310	321	462	402	428	447	405	425
21	242	209	218	326	310	317	441	403	422	443	396	418
22	212	205	209	324	305	314	445	409	425	434	389	418
23	219	197	208	326	302	315	472	415	440	442	388	414
24	210	188	202	322	315	318	438	391	418	436	392	420
25	246	209	223	316	306	312	442	393	428	481	421	443
26	263	244	253	429	299	317	519	392	429	497	442	466
27	287	261	270	344	305	319	445	396	417	506	429	480
28	290	272	282	617	287	334	412	390	399	528	455	494
29	287	280	283	316	296	306	470	410	440	530	464	501
30	298	281	288	342	276	319	497	439	463	531	469	508
31	---	---	---	345	325	335	493	454	475	---	---	---
MONTH	---	---	---	617	261	309	---	---	---	787	343	443

Temperature, water, degrees Celsius 

WATER YEAR OCTOBER 2002 TO SEPTEMBER 2003

DAY	MAX	MIN	MEAN	MAX	MIN	MEAN	MAX	MIN	MEAN	MAX	MIN	MEAN
	OCTOBER			NOVEMBER			DECEMBER			JANUARY
1	18.2	11.8	15.2	5.8	3.0	4.2	5.8	0.4	3.3	---	---	---
2	15.4	12.3	13.7	7.0	3.5	5.2	6.4	2.4	4.4	---	---	---
3	16.7	11.3	13.3	8.2	4.3	6.1	4.2	2.8	3.4	5.4	1.4	3.4
4	15.9	9.8	13.0	7.2	4.1	5.7	4.6	2.9	3.7	5.2	2.3	3.5
5	15.9	10.4	13.2	8.5	3.9	6.2	5.3	2.3	3.8	4.0	1.5	2.9
6	16.5	10.6	13.6	9.1	3.7	6.5	5.1	1.3	2.7	5.4	2.7	3.9
7	17.0	10.3	13.7	8.3	4.1	6.3	---	---	---	5.0	0.9	3.0
8	17.6	11.3	14.5	9.1	5.3	7.3	---	---	---	5.6	1.4	3.6
9	18.0	12.2	15.2	11.2	6.6	8.8	4.6	1.5	3.2	3.5	0.6	2.3
10	18.0	12.3	15.2	9.2	5.4	7.2	3.9	0.0	2.0	2.6	0.0	1.2
11	17.7	11.7	14.8	7.5	4.2	5.7	3.9	0.0	2.2	2.2	0.0	1.1
12	15.9	11.4	13.5	7.1	2.6	4.9	3.4	0.3	1.9	4.7	1.1	3.0
13	15.1	9.1	12.2	8.1	3.8	6.2	4.4	0.0	2.3	4.9	0.9	3.1
14	15.0	9.6	12.4	8.1	4.9	6.8	4.8	0.7	2.9	3.7	0.7	2.5
15	14.2	8.4	11.5	7.5	4.9	6.1	4.4	1.8	3.1	4.2	0.3	2.4
16	13.6	8.2	11.0	6.9	2.9	5.2	4.4	1.1	3.0	3.3	0.0	1.6
17	13.5	7.5	10.6	8.0	3.8	6.0	4.8	1.8	3.4	3.6	0.0	1.6
18	14.5	8.5	11.5	7.6	3.7	5.8	3.4	0.7	2.2	2.7	0.0	1.1
19	13.5	8.0	11.0	7.4	2.9	5.3	2.9	0.0	1.4	5.1	0.0	2.4
20	14.0	8.2	11.2	8.2	3.7	5.9	1.7	0.0	0.5	5.4	0.7	3.3
21	13.5	8.5	10.5	8.4	3.6	5.3	2.4	0.0	0.9	4.2	1.0	2.9
22	12.7	8.0	10.4	---	---	---	1.5	0.0	0.3	2.0	0.4	1.2
23	9.7	7.6	8.4	---	---	---	0.0	0.0	0.0	3.4	0.2	1.8
24	---	---	---	---	---	---	0.0	0.0	0.0	4.5	0.3	2.6
25	11.5	6.9	9.2	---	---	---	0.0	0.0	0.0	5.9	1.3	3.6
26	10.8	6.8	9.1	4.6	1.5	2.9	0.2	0.0	0.0	6.6	1.4	4.2
27	11.9	7.8	10.1	4.2	0.0	2.2	1.8	0.0	0.7	8.0	3.5	5.9
28	12.6	7.6	10.2	4.8	0.0	2.7	2.9	0.2	1.7	7.8	3.9	6.0
29	10.0	5.9	8.5	6.2	2.3	4.2	3.9	0.4	2.1	7.4	3.1	5.4
30	6.2	4.7	5.5	4.9	1.4	3.3	3.2	0.0	1.6	7.0	2.7	4.9
31	5.0	3.7	4.4	---	---	---	---	---	---	7.8	4.0	5.9
MONTH	---	---	---	---	---	---	---	---	---	---	---	---
	FEBRUARY			MARCH			APRIL			MAY
1	8.4	4.1	6.3	8.8	3.0	5.6	16.4	9.3	13.0	18.2	12.3	15.3
2	8.6	4.9	6.6	9.1	3.2	5.9	16.5	10.0	12.9	18.2	12.1	15.3
3	7.4	3.9	5.5	9.7	2.9	6.5	14.7	8.7	11.4	19.6	12.4	15.6
4	6.3	1.3	4.0	6.7	2.7	4.7	12.5	7.4	10.0	18.5	12.0	14.7
5	4.2	1.5	3.2	7.7	1.9	4.4	9.9	7.2	8.6	18.8	10.9	14.5
6	3.5	0.3	1.5	9.8	2.5	6.1	11.5	6.6	8.7	19.1	12.0	15.2
7	1.3	0.0	0.2	11.4	4.1	7.9	12.1	7.6	9.6	19.1	12.8	15.6
8	1.5	0.0	0.4	12.1	5.6	8.9	13.5	6.0	9.7	18.2	11.4	14.8
9	1.0	0.0	0.2	12.7	5.5	9.2	15.6	7.1	11.3	19.3	11.6	15.1
10	3.4	0.0	1.3	13.6	6.3	9.9	17.3	9.1	13.1	16.7	11.4	13.8
11	4.5	0.0	2.3	14.2	6.7	10.5	18.2	10.4	14.3	18.5	9.0	13.9
12	6.0	0.0	3.2	14.8	7.8	11.5	17.3	11.1	14.3	20.0	11.1	15.8
13	5.9	2.5	4.3	15.6	8.2	12.0	18.9	10.8	14.8	19.1	12.4	15.9
14	7.7	3.0	5.3	16.0	9.0	12.4	16.5	11.7	14.5	20.7	13.0	17.1
15	5.5	3.4	4.3	16.3	9.6	12.9	15.2	10.7	13.1	18.3	14.3	15.7
16	5.5	2.4	3.9	13.6	9.9	11.8	16.9	8.4	12.6	22.0	13.0	17.4
17	8.8	3.1	6.0	11.3	8.8	9.8	16.9	9.9	13.3	21.6	15.0	18.5
18	6.8	4.7	5.9	8.9	6.9	7.8	17.2	10.0	13.6	19.0	15.3	17.4
19	8.2	1.4	5.5	7.4	4.2	6.1	13.9	10.7	12.1	17.1	13.0	15.2
20	7.5	1.4	4.6	12.2	5.1	9.0	16.4	9.7	12.9	13.6	11.6	12.7
21	8.7	2.8	5.4	9.8	7.8	8.8	17.0	11.0	13.8	17.4	10.1	13.5
22	7.6	2.8	5.2	14.2	6.3	10.2	18.1	11.6	14.5	20.6	12.9	16.6
23	5.5	2.1	3.8	15.1	8.2	11.7	15.3	9.4	12.4	21.2	15.4	18.1
24	3.8	0.0	1.4	14.7	8.9	11.7	17.3	8.4	12.5	19.9	8.4	16.2
25	2.3	0.0	0.8	16.5	10.0	13.0	18.4	10.1	14.3	18.7	16.1	16.7
26	4.1	0.0	2.0	14.6	9.3	12.0	19.6	11.2	15.2	17.3	14.6	16.0
27	6.9	0.8	3.8	12.5	7.8	9.8	18.8	12.0	15.4	18.4	14.6	16.3
28	6.8	2.1	4.4	12.2	6.0	8.7	19.8	13.1	16.0	18.3	15.3	16.7
29	---	---	---	10.9	4.6	7.7	19.8	12.2	15.9	18.0	15.0	16.3
30	---	---	---	12.9	5.1	9.0	19.4	12.9	16.2	17.4	13.0	15.5
31	---	---	---	15.3	7.4	9.9	---	---	---	16.5	14.8	15.3
MONTH	8.8	0.0	3.6	16.5	1.9	9.2	19.8	6.0	13.0	22.0	8.4	15.7
	JUNE			JULY			AUGUST			SEPTEMBER
1	15.1	13.3	14.2	23.8	18.6	20.9	23.6	18.6	20.9	19.5	13.9	16.6
2	15.7	13.4	14.6	24.2	18.5	21.2	24.7	18.6	21.3	23.6	14.7	18.5
3	16.7	14.0	15.3	24.9	19.1	21.8	25.7	19.4	22.1	21.4	18.5	19.9
4	---	---	---	24.7	19.4	21.5	26.4	20.7	23.2	23.3	16.4	19.8
5	15.5	13.4	14.3	24.5	18.8	21.1	25.7	20.2	22.8	24.1	17.5	20.6
6	16.2	12.7	14.3	22.9	18.3	20.5	25.8	20.0	22.5	23.0	15.9	19.7
7	14.7	12.7	13.4	22.7	17.9	20.1	25.3	19.5	22.2	21.4	16.5	19.3
8	18.1	12.7	15.2	24.1	17.9	20.9	24.8	20.1	22.3	22.5	16.8	19.6
9	19.0	15.1	16.7	24.3	18.7	21.3	24.6	20.2	22.3	19.7	16.9	18.3
10	19.2	15.4	16.6	25.1	18.4	21.6	25.3	19.9	22.3	19.9	15.5	17.4
11	19.1	14.4	16.8	24.2	19.1	21.7	25.3	20.0	22.3	19.2	13.6	16.1
12	18.2	15.9	17.2	24.0	19.4	21.6	25.2	19.5	22.0	19.8	13.0	16.2
13	17.7	15.0	16.3	24.6	19.3	21.8	25.4	19.8	22.3	16.6	12.5	14.2
14	17.5	14.2	15.8	24.3	19.2	21.7	25.2	18.7	21.9	17.0	10.9	13.7
15	---	---	---	24.7	19.1	21.3	25.7	18.7	22.1	18.8	12.2	15.4
16	---	---	---	25.4	19.5	21.9	25.8	18.9	21.0	20.0	13.4	16.5
17	18.4	9.6	15.3	25.3	19.5	22.1	---	---	---	20.1	14.4	16.9
18	17.5	10.7	16.2	26.0	19.9	22.8	24.1	17.9	20.6	17.9	13.1	15.4
19	18.7	15.4	16.6	26.2	20.8	23.0	24.8	17.7	21.2	18.1	11.5	14.8
20	17.7	14.5	16.5	24.7	20.3	22.2	25.8	18.9	22.2	18.3	12.5	15.4
21	18.8	14.8	16.7	25.2	19.4	22.1	25.0	19.2	22.2	19.4	13.3	16.4
22	19.7	15.7	17.5	25.1	19.8	22.1	26.0	19.3	22.4	19.2	13.2	16.2
23	19.7	16.6	18.1	23.1	19.6	21.2	26.1	18.9	22.0	19.9	13.5	16.7
24	20.3	16.5	18.2	25.7	18.8	22.0	25.5	18.5	21.8	19.1	13.8	16.4
25	20.6	16.4	18.2	26.4	20.4	22.9	23.6	19.4	21.4	19.8	13.2	16.4
26	21.4	16.8	18.8	26.3	20.4	22.9	23.2	18.7	20.7	19.8	13.6	16.8
27	22.8	17.0	19.6	23.6	20.5	21.8	24.5	18.1	21.1	19.1	13.7	16.4
28	23.6	17.4	20.1	21.6	19.3	20.4	21.7	19.4	20.5	18.3	12.6	15.5
29	21.9	17.8	19.7	23.8	18.7	20.9	19.8	13.4	17.9	18.3	12.2	15.3
30	23.7	18.0	20.7	24.1	17.3	21.0	17.1	14.9	15.8	17.6	12.7	15.0
31	---	---	---	22.7	19.1	20.8	17.1	14.4	15.4	---	---	---
MONTH	---	---	---	26.4	17.3	21.6	---	---	---	24.1	10.9	16.8