Police say they will have a large presence around a Carmarthenshire country park as thousands of students start arriving for a four-day festival.
Up to 20,000 people will attend Beach Break Live at Pembrey Country Park.
The event, headlined by Vampire Weekend and Calvin Harris, sparked opposition in nearby Burry Port and Pembrey.
Festival director Ian Forshew said it was sold out with taxi firms, hotels and B&Bs already buzzing, and contracts worth £750,000 allocated locally.
The festival, which runs until Friday and is aimed exclusively at the student market, was granted a licence by Carmarthenshire council in April following a four-day hearing which was attended by objectors.
Supt Alun Harries of Dyfed-Powys Police said: "We are more than ready - we have gone through an intense period of planning since November when this event first came to our notice."
He said there would be a "much greater police presence" in the area including the country park.
"We will be holding meetings every evening in Burry Port Community Police Station at 6pm and I would urge people to come forward to tell us about any concerns they have so we can address them as soon as possible," he added.
He said all students entering the park, which is closed to the public throughout the week, would be subject to a search.
"We are going through a process of searching the area before and during the event to identify any issues in relation to drug criminality."
The RNLI said it was putting on extra lifeguards at Cefn Sidan beach throughout the week.
Deputy divisional manager Phil Davies said: "With up to 20,000 people attending, particularly if there is good weather, there will inevitably be a lot more people than usual going in the water and using the beach for this time of year.
"We are sure that if people get to know the RNLI's beach safety advice, which is being extensively promoted on site by our events team, then the chances of a serious incident on the beach will be greatly reduced."
Community councillor Joanna Davies said she and many others felt "really let down" that it was taking place.
"To also close the park completely for a week to local tax payers is galling and we fear for the wildlife and fauna down there and are desperately worried about the state the park will be left in afterwards," she added.
Festival organisers Student Seed Ltd hope Pembrey will become a permanent home to the event.
They say this year alone would be worth about £1m to local businesses and over the next five years the event would bring 100,000 university students to Carmarthenshire.
Around 1,000 will be employed running the festival with 15.5 miles (25km) of security fencing erected around the stages, activities and campsites.
Mr Forshew added: "Preparations have gone very well with no major hiccups.
"It's understandable for people to have concerns, particularly when something like this has not happened in the area before.
"But it's very much a self-contained and well managed event."