A Mater Dei Hospital water reservoir, situated in a nearby scheduled valley, was not built according to the permit stipulating it had to be underground, a planning authority case officer said yesterday.

The case officer said he had referred the matter to the Malta Environment and Planning Authority's enforcement section after noting that the reservoir did not respect the permit's outline and was larger than allowed.

The reservoir is situated in Wied Għollieqa, which Mepa considers to be an ecologically important valley.

The Health Ministry said the information about the reservoir was "rather surprising" as the Foundation for Medical Services had never received any form of Mepa notification on the matter during or after development. The foundation would contact Mepa to seek further clarification on the issue, a ministry spokesman said.

He pointed out that the reservoir was not for water containment but was a specialised basin that allowed water to filter away naturally and recharge the water table.

Mater Dei had an additional five underground water reservoirs. Four of these were used for potable water and the other fed the hospital's fire-fighting installations, he said.

The reservoir issue emerged during a Mepa board hearing that dealt with a landowner's application for the valley, in the limits of San Ġwann, to be re-scheduled.

The owner of a semi-detached villa explained that a section of his back garden had been scheduled as part of the valley. This was stopping him from building a pool that would enhance the value of his property. He asked Mepa to consider re-scheduling the area by removing his property from the scheduled part. He also argued that his villa was "sandwiched" between Mater Dei and the San Ġwann industrial estate.

During a previous sitting, held in May, the applicant's architect had pointed out that Mepa had allowed the construction of Mater Dei's reservoir and that his client's pool was just "a drop" compared to the reservoir.

The case officer yesterday pointed out that the reservoir had actually not been built according to permit. It was meant to be smaller and built underground. For this reason he had referred the issue for enforcement.

The case officer recommended that the villa owner's request for re-scheduling be turned down. "Building a pool is not a good enough reason for us not to schedule a part of this valley," he argued.

The villa owner's application for re-scheduling was turned down.

In a statement after the hearing, Mepa explained that Wied Għollieqa was "a spectacle of Mediterranean flora" that included various species of shrubs and bushes.

In 2005, it had allocated €35,000 of its Environment Initiative Partnership Programme funds towards the conservation of the valley. The project included the planting and maintenance of about 500 trees and the completion of the rubble walls and footpaths.