OHA Drinking Water Services
OR41
PWS ID: 00304 ---- ALDERWOOD WATER DEV CO
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
1Q2026 2DBP-01 5600 ALDER CT 0.073 0.032
4Q2025 Oct 21, 2025 2DBP-01 5600 ALDER CT 0.062 0.067 0.029 0.031
3Q2025 Aug 12, 2025 2DBP-01 5600 ALDER CT 0.051 0.079 0.022 0.032
2Q2025 May 27, 2025 2DBP-01 5600 ALDER CT 0.030 0.037 0.016 0.019
1Q2025 Feb 11, 2025 2DBP-01 5600 ALDER CT 0.017 0.022 0.010 0.013
4Q2024 Nov 12, 2024 2DBP-01 5600 ALDER CT 0.003 0.003 0 0
4Q2021 Nov 02, 2021 2DBP-01 5600 ALDER CT 0.032 0.035 0.017 0.014
3Q2021 Aug 03, 2021 2DBP-01 5600 ALDER CT 0.028 0.028 0.022 0.017
2Q2021 May 04, 2021 2DBP-01 5600 ALDER CT 0.031 0.030 0.023 0.024
1Q2021 Feb 02, 2021 2DBP-01 5600 ALDER CT 0.032 0.029 0.024 0.023
4Q2020 Nov 17, 2020 2DBP-01 5600 ALDER CT 0.033 0.033 0.024 0.026
3Q2020 Aug 04, 2020 2DBP-01 5600 ALDER CT 0.032 0.035 0.020 0.021
2Q2020 May 12, 2020 2DBP-01 5600 ALDER CT 0.035 0.032 0.021 0.021
1Q2020 Feb 04, 2020 2DBP-01 5600 ALDER CT 0.040 0.033 0.021 0.020
4Q2019 Nov 05, 2019 2DBP-01 5600 ALDER CT 0.033 0.039 0.016 0.019
3Q2019 Aug 22, 2019 2DBP-01 5600 ALDER CT 0.032 0.038 0.016 0.019
2Q2019 May 02, 2019 2DBP-01 5600 ALDER CT 0.029 0.034 0.016 0.016
1Q2019 Feb 05, 2019 2DBP-01 5600 ALDER CT 0.026 0.020 0.016 0.013
4Q2018 Nov 13, 2018 2DBP-01 5600 ALDER CT 0.035 0.032 0.024 0.019
3Q2018 Aug 07, 2018 2DBP-01 5600 ALDER CT 0.030 0.039 0.021 0.028
2Q2018 May 09, 2018 2DBP-01 5600 ALDER CT 0.024 0.031 0.018 0.022
1Q2018 Feb 06, 2018 2DBP-01 5600 ALDER CT 0.024 0.023 0.020 0.019
4Q2017 Nov 07, 2017 2DBP-01 5600 ALDER CT 0.027 0.016 0.025 0.017
3Q2017 Aug 10, 2017 2DBP-01 5600 ALDER CT 0.035 0.030 0.031 0.028
2Q2017 May 02, 2017 2DBP-01 5600 ALDER CT 0.044 0.044 0.034 0.037
1Q2017 Feb 07, 2017 2DBP-01 5600 ALDER CT 0.048 0.046 0.036 0.037
4Q2016 Nov 08, 2016 2DBP-01 5600 ALDER CT 0.045 0.032 0.031
3Q2016 Sep 20, 2016 2DBP-01 5600 ALDER CT 0.041 0.044 0.032 0.032
2Q2016 May 27, 2016 2DBP-01 5600 ALDER CT 0.040 0.044 0.030 0.037
1Q2016 Feb 02, 2016 2DBP-01 5600 ALDER CT 0.035 0.036 0.026 0.028
4Q2015 Nov 20, 2015 2DBP-01 5600 ALDER CT 0.033 0.031 0.022 0.024
3Q2015 Aug 25, 2015 2DBP-01 5600 ALDER CT 0.038 0.038 0.018 0.018
2Q2015 2DBP-01 5600 ALDER CT
1Q2015 2DBP-01 5600 ALDER CT