Council bosses have threatened to pull the plug on Scotland's biggest music festival if organisers do not drastically improve management of the event.

The stinging rebuke from Perth and Kinross Council comes after the 2015 festival, staged in the new location of Strathallan Estate for the first time, was plagued with transport problems, crowd safety issues and planning breaches.

The council has published a review which says the festival drew the largest number of post-event complaints in its 18-year history.

The report makes 36 recommendations but does note that several elements of the management plan did work effectively, including the company's controversial handling of a pair of nesting ospreys.

DF Concerts, which organises T in the Park, says it is "incredibly disappointed" not to meet the high standards that the council and festival-goers have, "quite rightly", come to expect, and has committed to making key changes to improve the event for 2016.

The company has already secured planning permission for three years, however, it has not secured a Public Entertainment Licence for 2016 yet.

Tickets are already on sale for the 2016 festival but if the council does not grant it a licence for 2016, the event cannot go ahead at Strathallan.

Campaign group Strathallan T Action group (Stag) is now calling for the planning permission to be reconsidered, saying: "This report throws into question whether the three-year planning permission should stand."

The report, by the council's director of environment services, Barbara Renton, states that the council will need "substantial" reassurance and evidence from DF Concerts that improvements have been made before officers can recommend that the festival gets the green light again.

The report states: "The 2015 T in the Park drew the largest number of post-event complaints and negative comments that Perth and Kinross Council had received about the event, during its 18-year history in the area.

"These comments were expressed by a range of sources, festival attendees, local residents, elected members, council staff and other public bodies involved in the event.

"The principal issues were: Significant traffic congestion at event egress (ticket holders departing at the end of the evening, once the arena entertainment stopped)...with patrons taking several hours to exit from the site and local road network.

"There was also significant traffic congestion for several hours during the day on Monday, July 11, both around the site and towards the Muthill area.

"Related to the above, safety concerns were expressed over large numbers of pedestrians on unlit minor roads at night, in heavy vehicular traffic. Perceptions of a general lack of crowd safety and security on site at the event.

"Disruption to the local community, particularly in relation to the traffic issues, antisocial behaviour and littering.

"In addition, planning officers reported repeated breaches of planning permission conditions, which were, in officers views, not addressed with sufficient rigour by the applicant, or their agent."

Liz Smith, MSP for Mid Scotland and Fife, said the public will now demand answers.

She said: "I welcome the publication of the long-awaited review into T in the Park. The 2015 event presented some very serious issues in terms of both security and access and it was clear that these caused considerable concern to many of those who attended the event and to many in the local community.

“The report describes these concerns. However, what I think most people want to know is what caused them to happen and how they will be addressed."

The report highlights "teething problems" at the new site and further states that: "These failings in event delivery were not typical of council officers’ experience of DF Concerts based on previous years` events at Balado.

"As a result, council staff will need substantial reassurances and evidence from DF Concerts that detailed plans will be prepared on time, and the event will be delivered more effectively, before officers could have confidence in recommending that the event takes place at Strathallan again."

A spokesman for Stag said: "It is depressing to read about the many breaches of conditions, particularly those which have had a negative impact on the environment and biodiversity at Strathallan.

"Six months on, there are still tents on the estate. The netting used to prevent kingfishers from nesting has been swept into the Machany in the floods.

"The evidence suggests that the site is not suitable for an event of this type and scale, and we are surprised that anyone at DF Converts continues to believe otherwise."

The elements which the council noted did work effectively include osprey management, as it claims no harm was reported to the birds during and after the festival.

It added that there were very few noise complaints, "far fewer than were normally received when the event was at Balado", and that aside from the traffic congestion at the site, "the overall local and national roads network was not negatively affected by TITP traffic."

T in the Park was previously held at Balado, which also falls under Perth and Kinross Council's remit.

Last week DF Concerts announced it had replaced the management team responsible for last year's festival including its head of security and head of traffic management.

It has brought in the firm which manages operations for the Glastonbury festival, APL Events, as well as two former senior police officers to look after security and traffic.

A spokeswoman for DF Concerts said: "We have worked with Perth and Kinross Council for the last 20 years to deliver T in the Park.

"We’re incredibly disappointed that, for the first time, we did not achieve the high standards of event management and customer service that we have set for ourselves which the Council and our customers have, quite rightly, come to expect.

"We note all points of Perth and Kinross Council’s report as published and remain focused on implementing key changes for 2016. We will not be disappointing ourselves, Perth and Kinross Council, the local community and especially our fans in 2016 and in truth, we look forward to being able to demonstrate that.

"Just last week we confirmed some new appointments to our management team. APL Events will now oversee the festival site management overseeing the necessary alterations to improve the onsite experience.

"These are just the first examples of the important changes that both Perth and Kinross council and our valued audience can expect for 2016. We’re entirely focused on delivering a fun, safe and successful festival that reminds everyone why T in the Park became Scotland’s favourite music festival in the first place."

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