Downing Street said the prime minister was being kept updated about events at Chevening, the retreat usually used by the foreign secretary.
The Chevening estate covers 3,000 acres stretching between Sevenoaks and Biggin Hill in Kent.
Its gardens include a lake, a maze and a double hexagonal walled kitchen garden.
Asked why Johnson was not personally visiting areas hit by the storm, a No.10 spokesperson said: “The prime minister will receive regular updates on this.
“It’s right that Defra and the secretary of state for the environment are leading on this.”
Johnson was heckled by locals when he visited flood-hit areas of Yorkshire in November.
Storm Dennis has lashed the country with 90mph winds and drenched some places with more than a month’s worth of rain in 48 hours.
Over the weekend major incidents due to flooding were declared in South Wales, Worcestershire, Herefordshire and Shropshire.
Labour leadership contender Keir Starmer said today it was “an appalling decision” not to hold an emergency Cobra meeting on the flooding.
“The recent flooding is a stark reminder that the government is not doing enough to get to grips with the climate crisis,” he said.
Ministers should be taking a lead on this situation, not ducking their responsibilities.
“I would urge the prime minister to reconsider this decision and give communities the support they need to deal with the horrendous flooding.”
The government said it had activated the Bellwin scheme to provide emergency financial assistance to storm-hit areas.
Under the scheme, local authorities dealing with the storm’s impact can apply to have 100% of eligible costs above a threshold reimbursed by the government.