Recent complaints by rural water customers about earthy, musty tasting water are being blamed on blue-green algae bloom at Lake Rathbun in Iowa.

Customers of the Consolidated Public Water Supply District #1 of Scotland County may recently have noticed a change in the taste of their water. Representatives of the rural water provider recently announced algae blooms at the water source, Lake Rathbun, are likely to blame for current earthy and musty tastes in the H2O being reported by consumers.

The Rathbun Regional Water Association (RRWA) which manages the water treatment process for raw water from the lake that is sold to regional customers like the CPWSD#1, insists the water is safe to drink, but does acknowledge the taste changes which are being blamed on blue-green algae.

“Earthy and musty tastes and odors in RRWA’s water are most likely caused by two naturally occurring chemical compounds that can be found in Rathbun Lake,” an alert on the company’s website is reporting. “These compounds are geosmin and 2-methylisoborneol.”

The company notes that cyanbactera, or the blue-green algae, are the most likely causes of the two byproducts having the adverse effect on the treated water.

“RRWA’s water treatment does remove some of the geosmin and 2-methylisoborneol in the water from Rathbun Lake,” the company said. “However, many individuals are very sensitive to the tastes and odors caused by extremely small concentrations of these compounds.”

The RRWA does take steps to help prevent these side effects of the summer and fall algae blooms, which are most frequently blamed on warm water conditions and an over abundance of nutrients such as nitrogen and phosphorus according to the Environmental Protection agency.

In addition to granular carbon filtering to remove taste and odor compounds, the RRWA uses sodium permanganate to break down substances in the water.

Another proactive step being taken to try to prevent algae is a growing partnership with landowners in the lake’s watershed working to limit nutrient runoff.

The RRWA caps off its regularly scheduled monitoring process for the treatment and distribution systems with its active water main flushing program to help further improve water quality in the system.

Josh McSparren of CPWSD#1 indicated local customers recently have been reporting the taste concerns to the Memphis office. He said the district experienced similar circumstances last year around this point on the calendar.

The RRWA said that conditions for algae blooms at the lake are at their worst in late summer and early fall.

“RRWA encourages our customers to contact us with any questions, concerns, and comments about their drinking water. For non-emergencies, RRWA customers can call 1-800-233-8849 between the hours of 8:00 am and 4:30 pm Monday to Friday. For emergencies, RRWA customers can call the same number, 1-800-233-8849, at any time. RRWA customers can also send emails to”