Skip to main content
Back To Top Top Back To Top
This website publishes administrative rules on their effective dates, as designated by the adopting state agencies, colleges, and universities.

Rule 3745-90-03 | Harmful algal blooms - monitoring.

 

This rule applies to all surface water systems and consecutive water systems receiving water from a surface water source. Seasonal systems shall monitor in accordance with this rule during the system's operating season.

(A) Surface water systems.

(1) Cyanobacteria screening.

Surface water systems shall monitor with a minimum of one sample at least once every two weeks for cyanobacteria screening during harmful algal bloom season.

(2) Routine microcystins monitoring.

(a) Requirements during harmful algal bloom season (June through November).

(i) Surface water systems shall monitor for microcystins analysis with a minimum of one sample from each raw water sampling point once every two weeks and on the alternate week of cyanobacteria screening sample.

(ii) If microcystins are detected at a raw water sampling point, weekly monitoring at that raw water sampling point and the finished water sampling point shall be conducted beginning no later than twenty-four hours following the detection. When microcystins are not detected in at least two consecutive weekly samples from both the raw water sampling point and the finished water sampling point, then monitoring once every two weeks may resume in accordance with paragraph (A)(2)(a)(i) of this rule.

(iii) If cyanobacteria screening results indicate microcystin production genes greater than five gene copies per microliter and concurrent weekly data for microcystins are not available for raw or finished water samples, the water system must collect a sample at the finished water sampling point within twenty-four hours of notification of the detection for microcystins analysis. If microcystins are not detected in raw and/or finished water samples, then monitoring once every two weeks may resume in accordance with paragraph (A)(2)(a)(i) of this rule.

(b) Requirements during off-season (December through May).

Surface water systems shall monitor with a minimum of one sample from each finished water sampling point at least once every two weeks for microcystins analysis.

(3) Revised cyanobacteria screening or routine microcystins monitoring.

The required cyanobacteria screening or routine microcystins monitoring may be revised (decreased, increased or discontinued) at the discretion of the director. When establishing the revised schedule, the director may consider cyanobacteria screening data collected in accordance with this rule, microcystins data, and other information provided by the public water system including data from other screening tools (such as phycocyanin sensors or phytoplankton enumeration) and treatment information. Surface water systems shall monitor in accordance with the revised cyanobacteria screening or microcystins monitoring schedule established by the director.

(4) Response to microcystins action level exceedance.

If microcystins exceed an action level established in paragraph (A)(1) or (A)(2) of rule 3745-90-02 of the Administrative Code in routine samples collected at the finished water sampling point, the public water system shall do the following:

(a) As soon as possible, but no later than twenty-four hours after receiving the results of the initial action level exceedance, collect one resample from each raw water sampling point and one resample from each finished water sampling point. Analysis of resamples must be completed within twenty-four hours of collection. These resamples satisfy the requirement for increased microcystins monitoring samples as set forth in paragraph (A)(4)(d) of this rule.

(b) Within twenty-four hours of collecting the resamples, collect one repeat sample from each raw water sampling point and one repeat sample from each finished water sampling point. Analysis of repeat samples must be completed within twenty-four hours of collection. These repeat samples satisfy the requirement for increased monitoring samples as set forth in paragraph (A)(4)(d) of this rule.

(c) If the microcystins concentration exceeds the action level in the resample or repeat sample collected at any finished water sampling point in accordance with paragraph (A)(4)(a) or (A)(4)(b) of this rule, as soon as practical but no later than three hours after receiving the resample or repeat sample results, the surface water system shall notify all consecutive systems served by the water system. If a water system collects samples at representative distribution sampling points in accordance with procedures developed as part of the contingency plan required by rule 3745-85-01 of the Administrative Code, the director may allow the system to limit distribution of the public notice in accordance with rule 3745-85-01 of the Administrative Code. Distribution system monitoring may be required by the director based on sampling results and other relevant circumstances.

(d) Conduct increased mycrocystins monitoring of three times per week.

The frequency of microcystins monitoring shall be one day per week at raw water sampling points and increased to three days per week at finished water sampling points. Increased monitoring (three days per week) shall include analysis within twenty-four hours of sample collection. The resample and repeat samples collected in accordance with paragraphs (A)(4)(a) and (A)(4)(b) of this rule satisfy the requirement for increased monitoring.

Routine microcystins monitoring may resume in accordance with paragraphs (A)(2)(a) and (A)(2)(b) of this rule, once microcystins are not detected in finished water in two consecutive samples collected on separate calendar days.

(e) Conduct public notification in accordance with rule 3745-90-06 of the Administrative Code.

(B) Consecutive water systems receiving water from an in-state surface water system.

In accordance with paragraph (A)(4)(c) of this rule, consecutive water systems served by in-state surface water systems shall be notified by the parent system if microcystins concentration exceeds the action level in resample or repeat samples collected at any finished water sampling point. If a water system collects samples at representative distribution sampling points in accordance with procedures developed as part of the contingency plan required by rule 3745-85-01 of the Administrative Code, the director may allow the system to limit distribution of the public notice in accordance with rule 3745-81-32 of the Administrative Code. Distribution system monitoring may be required by the director based on sampling results and other relevant circumstances. Water systems shall conduct public notification in accordance with rule 3745-90-06 of the Administrative Code.

(C) Consecutive water systems receiving water from an out-of-state surface water source.

(1) Routine microcystins monitoring.

(a) Requirements during harmful algal bloom season (June through November).

Consecutive water systems receiving water from an out-of-state surface water source shall monitor with a minimum of one sample from each finished water sampling point at least weekly for microcystins analysis.

(b) Requirements during off-season (December through May).

Consecutive water systems receiving water from an out-of-state surface water source shall monitor with a minimum of one sample from each finished water sampling point at least once every two weeks for microcystins analysis.

(c) Revised routine microcystins monitoring.

The required microcystins monitoring may be revised (decreased, increased or discontinued) at the discretion of the director. When establishing the revised schedule, the director may consider microcystins data, and other information provided by the public water system including data from screening tools (such as phycocyanin sensors or phytoplankton enumeration) and treatment information. Consecutive water systems shall monitor in accordance with the revised routine microcystins monitoring schedule established by the director.

(2) Response to microcystins action level exceedance.

If microcystins exceed an action level established in paragraph (A)(1) or (A)(2) of rule 3745-90-02 of the Administrative Code in routine samples collected at the finished water sampling point, the public water system shall do the following:

(a) As soon as possible, but no later than twenty-four hours after receiving the results of the initial action level exceedance, collect one resample from each finished water sampling point. Analysis of resamples must be completed within twenty-four hours of collection. This resample satisfies the requirement for increased microcystins monitoring samples as set forth in paragraph (C)(2)(d) of this rule.

(b) Within twenty-four hours of collecting the resamples, collect one repeat sample from each finished water sampling point. Analysis of repeat samples must be completed within twenty-four hours of collection. This repeat sample satisfies the requirement for increased microcystins samples as set forth in paragraph (C)(2)(d) of this rule.

(c) If the microcystins concentration exceeds the action level in the resample or repeat sample collected at any finished water sampling point in accordance with paragraph (C)(2)(a) or (C)(2)(b) of this rule, as soon as practical but no later than three hours after receiving the resample or repeat sample results, the public water system shall notify all consecutive systems served by the water system. If a water system collects samples at representative distribution sampling points in accordance with procedures developed as part of the contingency plan required by rule 3745-85-01 of the Administrative Code, the director may allow the system to limit distribution of the public notice in accordance with rule 3745-81-32 of the Administrative Code. Distribution system monitoring may be required by the director based on sampling results and other relevant circumstances.

(d) Conduct increased microcystins monitoring of three days per week.

The frequency of microcystins monitoring at finished water sampling points shall be increased to three times per week. Increased monitoring shall include analysis within twenty-four hours of sample collection. The resample and repeat samples collected in accordance with paragraphs (C)(2)(a) and (C)(2)(b) of this rule satisfy the requirement for increased monitoring.

Routine microcystins monitoring may resume in accordance with paragraph (C)(1)(a) or (C)(1)(b) of this rule once microcystins are not detected in two consecutive samples collected on separate calendar days at the finished water sampling point.

(e) Conduct public notification in accordance with rule 3745-90-06 of the Administrative Code.

(D) Monitoring extension.

Upon a request from a public water system, the director may agree to extend the twenty-four hour monitoring requirement for increased, resample, repeat or distribution samples required pursuant to this rule on a case-by-case basis when the public water system has a logistical problem collecting samples within twenty-four hours or analyzing samples in accordance with the requirements of this chapter. When an extension is agreed to by the director, the director shall specify in writing how much time the public water system has to monitor. Examples of potential logistical problems include, but are not limited to:

(1) Extreme weather conditions create unsafe travel or on-site conditions for the person collecting the sample.

(2) Limited certified laboratory capacity on weekends and holidays.

(E) Violations.

Failure to comply with monitoring requirements in paragraph (A)(1), (A)(2), (A)(3), or (A)(4)(d) (C)(1), or (C)(2)(d) of this rule is a monitoring violation and requires the public water system to provide tier 3 public notification in accordance with rule 3745-81-32 of the Administrative Code. Failure to comply with resample and repeat sample requirements in paragraph (A)(4)(a), (A)(4)(b), (C)(2)(a) or (C)(2)(b) of this rule is a monitoring violation and requires the public water system to provide a tier 1 public notification accordance with rule 3745-81-32 of the Administrative Code.

Last updated November 1, 2022 at 9:07 AM

Supplemental Information

Authorized By: 3745.50, 6109.04
Amplifies: 3745.50, 6109.04
Five Year Review Date: 11/1/2027
Prior Effective Dates: 6/1/2016