The National Capital Commission has the power to veto the Chateau Laurier addition.

House of Commons Ottawa. July 6, 1908. The Hon. William Pugsley (Minister of Public Works) regarding the design of the Grand Trunk Railway hotel. "The hotel shall be constructed within two years from the date of the said grant, (with) construction to be in accordance with plans approved by the government of Canada."  (The National Capital Commission cannot approve or reject the design of the Chateau Laurier addition because "The hotel is privately owned." But the Grand Trunk was a private company until 1918; and the federal Department of Public Works had control over the architectural plans of the Grand Trunk/Chateau Laurier hotel in 1908.)

"The NCC's mission statement reflects it's mandate---to use the Capital to communicate Canada to Canadians; to make the Capital a meeting place for Canadians; and to safeguard and preserve national treasures in the Capital." (1993-94 NCC Annual Report-Executive Summary-Page 9/36.)

"Too many modern cities have paid the price of uncontrolled and disharmonious development. That is why Canada's Parliament appointed the NCC to guard against inappropriate design use and land use in the Canadian Capital. The Commission has been authorized to examine all applications for design approval, land use changes, realty transactions and demolitions affecting federal property in the region, rejecting those that are inappropriate or suggesting changes to make others appropriate." (1994-1995 Annual Report of the National Capital Commission, page 19/50.)

Letter of concern from UNESCO to the Government of Canada. 4 November, 2019. The Chateau Laurier proposed expansion. (Ottawa.) Background:

"In May 2019 the World Heritage Centre, in accordance with paragraph 174 of Operational Guidelines for the implementation of the World Heritage Convention, contacted the State Party regarding information received on a proposed addition to the Chateau Laurier Hotel, a building which, together with the Canadian Parliament Buildings, frames the Ottawa Locks where the Rideau Canal meets the Ottawa River. Of concern was that the proposal included elements that could negatively impact on the Outstanding Universal Value (OUV) of the property. In June of 2019 the State Party provided comment."

"The Chateau Laurier hotel is a privately-owned building. The proposal is for the construction of a seven-storey, 147 room addition to the rear of the building, overlooking Major's Hill Park. The proposal partially overlooks the Rideau Canal at Ottawa Locks, and is planned in a contemporary style, connecting to limited areas on the Chateau Laurier's east and west wings. The development retains the Chateau Laurier in its entirety and will be built on the site of the former parking garage. The Chateau Laurier and the parking garage building existed at the time of the Rideau Canal's inscription on the World Heritage List on 2007. The proposed seven-storey addition is located in an area immediately adjacent to the Ottawa Locks, a highly significant and iconic component of the property. The Ottawa Parliament Buildings and Chateau Laurier contribute significantly to the setting for the Ottawa Locks and one of the most significant landscape views of the World Heritage property."

"Parks Canada has, in the role of adjacent landowner, provided comments and input since 2015 on the proposal and application. As the Chateau Laurier hotel is within the viewshed of the Ottawa Locks, feedback has been focused on compatibility of the proposed hotel addition with the historic setting of, and the visual impact to, the Ottawa Locks."

"Evolutions to the proposed design reduced the height and increased the setback of the addition from the historic Chateau Laurier to support the prominance of the heritage building in the landscape; to minimise the visual impact of the approach up the locks from the Ottawa River; and to open up the view into the hotel's original rear courtyard and out to the Ottawa Locks and Parliament Hill."

"On 27 June 2018, on recommendation from the City's Planning Committee, the City Council conditionally approved the application to alter the Chateau Laurier building, advising that more work was required to make the addition more visually compatible with the existing hotel. On 13 June 2019, the City's Planning Committee approved the Site Plan control application. On 10 and 11 July 2019, the City Council upheld the heritage permit approval." Discussion: "The construction of a proposed addition to the north side of the Chateau Laurier building adjacent to the Rideau Canal World Heritage property holds the potential to negatively affect the OUV (Outstanding Universal Value) of the property. It is therefore essential that utmost care be taken in assessing potential impacts before any irrevocable decisions are made."

"The viewscape framed by the Canadian Parliament Buildings and the Chateau Laurier hotel overlooks the Ottawa Locks, which is the largest set of locks within the entire Rideau Canal World Heritage property. This viewscape has been recognized for its importance by the Canadian government in its "Landscape Character Assessment and Planning and Management Recommendations (2013)." The recommendation list the Ottawa Locks and associated heritage buildings, and views to the Parliament Buildings and Chateau Laurier, as quintissential to the Rideau Canal experience."

"At the time of nomination, the City of Ottawa 20/20 official plan called for Cultural Heritage Impact Studies to ensure that the "visual quality of the waterway as well as natural and cultural features are evaluated."

The Patterson's Creek Pavilion, Ottawa. An appropriate design and size for a building beside the Rideau Canal UNESCO World Heritage Site.