The DA in Capricorn district municipality in Limpopo has accused the municipal manager of "lacking integrity and ethical conduct".
Some officials, who would not be named, claimed Merriam Molala was "in the habit of not consulting other relevant organs" before arriving at crucial decisions.
They claimed Molala's leadership style was a "setback to the municipality".
Frans Letwaba, of the Democratic Alliance, accused Molala of l acking integrity and ethical conduct.
Mayor Motalane Monakedi, however, described the allegations as baseless.
He said he was happy with Molala's performance, but noted that she needed to improve some aspects of her work.
Meanwhile, the officials said the municipality's performance had retrogressed for the first time since its inception.
Before Molala joined the municipality in November last year, the municipality had been among the best-performing in the country.
The municipality even won a Vuna award in 2005 for its performance.
Molala was also accused of breaching standing orders by failing to provide councillors with agendas prior to a council meeting recently.
"Today the executive mayor has to step in and assist with drawing up the budget and 'the new structure'.
"He also sits with managers to do crisis management," claimed a source.
However, Monakedi has denied these allegations as well.
The source alleged that staff morale was at its "lowest ebb" with a majority of employees saying they "were only sticking around because of the better salaries the municipality was offering," said the source.
Molala could not be contacted for comment yesterday.