Ottawa's Dominion Observatory campus should be protected by the United Nations.

Canada is one of the founders of the United Nations Educational, Scientific and Cultural Organization. UNESCO was created to protect heritage buildings and landscapes that are threatened by acts of war, weather events, encroachment and modern construction.
The buildings in question:
1.)  Dominion Observatory
2.)  Observatory House
3.)  Geophysical Laboratory
4.)  Machine Room
5.)  Geophysical Data Room
6.)  Seismology Room
7.)  Azimuth Mark or South Azimuth
8.)  Photo equatorial building.

The threats 
1.)  The tallest buildings in Ottawa will be constructed in the Carling/Preston area according to a municipal document called "The Preston-Carling Area Secondary Plan". The Dow's Lake parking lot and 870 Carling Avenue are currently zoned to facilitate the construction of residential towers, and local politicians are encouraging intensification on land close to arterial streets (like Carling Avenue) and the O-Train.
2.)  Canada is the only country in the G8 that has no legislation to protect national historic sites. That includes the Kingston Penitentiary, Prison for Women and Toronto's Fort York.
3.)  During the 1980's the Government of Canada sold the Dominion Observatory in Victoria British Columbia to a provincial agency.
4..)  Roads within the campus including Maple Lane are being widened.
5.)  A massive health care facility is being constructed on the grounds of the nearby Sir John Carling site. Land is needed for:
--services for the care of dependents;
--dental, pharmacy and educational services;
--use as accommodation,clinics, food and services facilities and retail;
--uses practised in community health hubs as may be directed by the Minister from time to time including community centres, athletic facilities and other non-governmental organizations providing public services.
--diagnostic laboratories;
--educational and research institutions;
--parking (which includes, without limitation, the performance of the NCC sublease) and transit services;
--such other services or uses required by the Minister or Province for the treatment of patients to be provided by a Hospital;
--multi-use pathways connected to the community;
--the performance of the Permitted Title.
From: Ground lease agreement-Greenspace Alliance of Canada's Capital-Page 8/70.

"Surrounding Space" means the lands abutting or being or lying beside or around the Lands (which includes, without limitation, HMCS Carleton, Carling Avenue, Preston Street, Prince of Wales and the AAFC Lands.)
From: Ground lease agreement-Greenspace Alliance of Canada's Capital,2018, Page 10/70.

Why the Dominion Observatory Campus qualifies for designation as a UNESCO World Heritage Site:
1.)  The Dominion Observatory in Ottawa is modeled after the Royal Observatory in Greenwich, England which was designed by Sir Christopher Wren. The Royal Observatory is protected by UNESCO.
2.)  The campus is endangered by the encroachment of a health care facility, tall buildings and the loss of the South Azimuth due to the widening of Maple Lane (the North Azimuth was demolished when Carling Avenue was widened).
3.)  The Campus meets all the criteria for inclusion as a World Heritage Site:
World Heritage Criteria
To be included on the World Heritage List, sites must be of outstanding universal value and meet at least one of the ten selection criteria:
Definition of Cultural Heritage
For the purposes of the World Heritage Convention the following are considered Cultural Heritage:

• monuments: architectural works, works of monumental sculpture and painting, elements or structures of an archaeological nature, inscriptions and cave dwellings and combinations of features , which are of outstanding universal value from the point of view of history, art or science;
• groups of buildings: groups of separate or connected buildings which, because of their architecture, their homogeneity or their place in the landscape, are of outstanding universal value from the view of history, art or science;

A brief timeline of Canada's cooperation with UNESCO:

1945 - The Constitution of UNESCO is signed in London, England on November 16, 1945. Canada is one of the founding members. Vincent Massey, High Commissioner for Canada to the United Kingdom leads the Canadian Delegation at the founding conference in London. (I find it bitterly ironic that a relative of Vincent Massey designed the Sir John Carling Building, which was demolished to facilitate the relocation of the Civic Hospital. Hart Massey also designed the SJC cafeteria annex, which is also being demolished by the Civic.)

1959 - Prime Minister John Diefenbaker attended the Agency's Annual General Meeting in Ottawa.

1972 - The Convention Concerning the Protection of the World Cultural and Natural Heritage is adopted by UNESCO. Protected cities and landscapes include :
Lunenberg, Nova Scotia.
The Historic District of Old Quebec - Quebec City.
L'Anse aux Meadows National Historic Site.
(In my opinion the following landscapes and buildings should also be protected:
--The entire Central Experimental Farm.
---The entire Village of Portsmouth in Kingston, Ontario, including the Kingston Pen, Prison for Women, Church of the Good Thief, the Rockwood Asylum, Corrections Canada Museum, Isabel MacNeill Halfway House and Corrections Canada training centre on Union Street.
---The 1,000 lighthouses that were divested by Fisheries and Oceans Canada including Peggy's Cove.
---Royal Military College in Kingston, Ontario. The Royal Roads Military College in Victoria, British Columbia was sold by the Canadian government.

---The Napoleonic Martello Towers that are located throughout Canada and some are crumbling.)

The Victoria, British Columbia Dominion Observatory was sold to a provincial government agency during the mid-1980's.

A 2009 stamp from Canada Post featuring images of the Victoria Observatory and the Horsehead Nebula.

The Photo Equatorial Building may be removed according to a document called "NCC Federal Site Review for the New Civic Campus of the Ottawa Hospital" November 2016.