A spokeswoman for Scottish Water said the company couldn't discuss matters of national security. A report in The Herald newspaper said that security service MI5 had advised the Home Office to instruct Scottish Water to take the precautions.
The paper said that MI5 had called for fencing around the reservoir to be at least three meters high. It also reportedly called for a central walkway and filtration plant that divides the reservoir to be sealed off to the public.
A spokesman for Scottish Water said: "It's a matter of national security and we can't discuss that. That's for the Home Office to decide. If the Home Office expresses to us that things have to be implemented we will have to comply with that, but we can't comment on the report."
A Scottish Executive spokesman added: "As the sponsoring body of Scottish Water, we would give our support to them on any such instruction from the UK Government involving national security."
The Home Office described the report as "speculation" and said it would not discuss security matters. Security concerns have soared in the wake of 11 September and in the build-up to a possible war against Iraq.
The reservoir lies within Mugdock Country Park, near Milngavie and paths around it are popular with walkers. Last year, an outbreak of the cryptosporidium bacteria at the reservoir led to 150,000 households in Glasgow and Clydebank having to boil tap water for days.
Source: Daily Observer
