OHA Drinking Water Services
OR41
PWS ID: 00798 ---- SEAL ROCK WATER DISTRICT
LRAAs and OELs

LRAA = Locational running annual average; OEL = Operational evaluation level. Learn about OELs here.
Averages are subject to change as new data is taken into consideration.

TTHM MCL = 0.080 mg/L,  HAA5 MCL = 0.060 mg/L.  MCL exceedances are indicated with red text.

Monitoring
Period		 Last
Sample		 Sample
Point		 Location TTHM
LRAA		 TTHM
OEL		 HAA5
LRAA		 HAA5
OEL
4Q2025 Nov 12, 2025 2DBP-01 1801 NW CANAL ST 0.052 0.056 0.030 0.029
4Q2025 Nov 12, 2025 2DBP-02 540 SE 123RD ST 0.060 0.066 0.027 0.027
3Q2025 Sep 03, 2025 2DBP-01 1801 NW CANAL ST 0.049 0.049 0.033 0.029
3Q2025 Sep 03, 2025 2DBP-02 540 SE 123RD ST 0.057 0.067 0.030 0.028
2Q2025 Jun 18, 2025 2DBP-01 1801 NW CANAL ST 0.053 0.052 0.037 0.036
2Q2025 Jun 18, 2025 2DBP-02 540 SE 123RD ST 0.051 0.048 0.030 0.030
1Q2025 Mar 12, 2025 2DBP-01 1801 NW CANAL ST 0.049 0.049 0.036 0.037
1Q2025 Mar 12, 2025 2DBP-02 540 SE 123RD ST 0.048 0.047 0.031 0.030
4Q2024 Dec 04, 2024 2DBP-01 1801 NW CANAL ST 0.048 0.050 0.035 0.037
4Q2024 Dec 04, 2024 2DBP-02 540 SE 123RD ST 0.048 0.051 0.031 0.033
3Q2024 Aug 14, 2024 2DBP-01 1801 NW CANAL ST 0.057 0.052 0.040 0.035
3Q2024 Aug 14, 2024 2DBP-02 540 SE 123RD ST 0.049 0.051 0.028 0.030
2Q2024 Jun 12, 2024 2DBP-01 1801 NW CANAL ST 0.058 0.052 0.042 0.038
2Q2024 Jun 12, 2024 2DBP-02 540 SE 123RD ST 0.051 0.044 0.033 0.028
1Q2024 Mar 13, 2024 2DBP-01 1801 NW CANAL ST 0.058 0.057 0.041 0.043
1Q2024 Mar 13, 2024 2DBP-02 540 SE 123RD ST 0.049 0.050 0.031 0.032
4Q2023 Dec 21, 2023 2DBP-01 1801 NW CANAL ST 0.056 0.068 0.038 0.047
4Q2023 Dec 21, 2023 2DBP-02 540 SE 123RD ST 0.054 0.053 0.034 0.030
3Q2023 Sep 13, 2023 2DBP-01 1801 NW CANAL ST 0.041 0.052 0.025 0.034
3Q2023 Sep 13, 2023 2DBP-02 540 SE 123RD ST 0.047 0.059 0.030 0.040
2Q2023 Jun 07, 2023 2DBP-01 1801 NW CANAL ST 0.032 0.035 0.019 0.021
2Q2023 Jun 07, 2023 2DBP-02 540 SE 123RD ST 0.038 0.037 0.023 0.023
1Q2023 Mar 01, 2023 2DBP-01 1801 NW CANAL ST 0.028 0.030 0.015 0.018
1Q2023 Mar 01, 2023 2DBP-02 540 SE 123RD ST 0.039 0.044 0.023 0.028
4Q2022 Nov 30, 2022 2DBP-01 1801 NW CANAL ST 0.020 0.020 0.007 0.007
4Q2022 Nov 30, 2022 2DBP-02 540 SE 123RD ST 0.023 0.023 0.008 0.008
3Q2014 Sep 03, 2014 2DBP-01 1801 NW CANAL ST 0.019 0.023 0.005 0.008
3Q2014 Sep 03, 2014 2DBP-02 540 SE 123RD ST 0.017 0.021 0.005 0.008
2Q2014 Jun 04, 2014 2DBP-01 1801 NW CANAL ST 0.011 0.014 0.002 0.004
2Q2014 Jun 04, 2014 2DBP-02 540 SE 123RD ST 0.010 0.013 0.003 0.004
1Q2014 Mar 05, 2014 2DBP-01 1801 NW CANAL ST 0.007 0
1Q2014 Mar 05, 2014 2DBP-02 540 SE 123RD ST 0.007 0.001
4Q2013 Dec 04, 2013 2DBP-01 1801 NW CANAL ST 0.004 0
4Q2013 Dec 04, 2013 2DBP-02 540 SE 123RD ST 0.003 0