Tender irregularities, disciplinary action against senior staff members and the shutdown of a forensic investigation are expected to be discussed at a special council meeting of the City of Cape Town on Tuesday morning.

In what is being described as an unprecedented move, the city's Democratic Alliance (DA) caucus is believed to have requested the meeting to force the city to reopen investigations into wide-ranging corruption allegations against urban development commissioner Melissa Whitehead.

Whitehead has recently been at the forefront of a series of allegations, including that she employed close friends in senior positions, irregularly benefited from a Chinese electrical bus tender and favoured a particular bid in the city's delayed Foreshore project.

Senior sources within the DA caucus told News24 that City of Cape Town manager Achmat Ebrahim and Mayor Patricia de Lille had shut down a forensic investigation into Whitehead.

The sources alleged that Ebrahim threatened a forensic official under instruction from De Lille to discontinue the investigation.

The official is said to have been removed from the city's administration.

Mayoral committee member for transport and urban development Brett Herron is also accused of overlooking Whitehead's activities despite being her direct superior.

City of Cape Town speaker Dirk Smit was asked about the allegations. He however merely confirmed to News24 that the "confidential" council meeting would take place to discuss the "disciplinary regulations related to senior managers".

Smit said the meeting was requested by De Lille, but said he could not reveal further details.

The meeting was set to start at 10:00.

DA metro leader Grant Twigg did not deny that the council meeting would discuss the allegations surrounding Whitehead, but said the council meeting was "confidential".

De Lille's spokesperson Zara Nicholson failed to respond to detailed questions by the time of publication.

Tuesday's council meeting marks the latest in a series of controversies surrounding the City of Cape Town and De Lille's administration.

Council members have accused De Lille of pushing through a centralised decision-making structure with the introduction of the city's Organisational Development and Transformation Plan.

In September, News24 reported that De Lille ordered that the city's special investigations unit (SIU) be shut down after it unearthed shocking claims that some city councillors may have been allegedly involved in a murder. There were also allegations that upgrades to De Lille's Pinelands home were paid for illegally by the city.

In October, De Lille and mayoral committee member for safety, security and social services JP Smith were placed on special leave from the DA's metropole activities following a public spat.

De Lille accused Smith of dragging her name through the mud with claims he had made against her about the closure of the SIU.

In the same month, the City of Cape Town angered Clifton and Camps Bay residents after it emerged that a controversial R1-billion tender was awarded to sell and transform stretches of land in the highly-desired suburbs.

De Lille and the city are also accused of not having responded in time to the ongoing drought crisis.

The City has adjusted several of its water augmentation targets, including decreasing its original goal of 500-million litres per day total water consumption to roughly 200-million litres.

Despite De Lille's promise that a "well-run city will not run out of water", she announced last week that the city's water is set to run out by May 2018.