CITIES GLOBALLY UNITED
CITIES GLOBALLY UNITED

CITIES GLOBALLY UNITED / 18

Signal observatory

Small, dated observations that deserve a closer look. A signal is a question, not a conclusion.

What counts as a signal

An observation, a target year that has passed or is approaching, or a gap in the evidence. Each signal names its source and what would confirm or refute it. Signals are reviewed monthly; none is a forecast.

Mexico City · Ground and water

Parts of the metropolitan area sink by more than 2 cm a month

Observation

What was observed
NASA reports radar measurements from 25 October 2025 to 17 January 2026. It links the compaction of the old lakebed to long-running groundwater pumping and the weight of the city.
What would confirm or refute it
Repeated measurements, ground stations and groundwater-extraction records for the same districts would confirm or refute the pattern.
Source
NASA · U.S.-Indian space mission maps extreme subsidence in Mexico City (2026-04-29)
Next review
2026-11-06

Freetown · Green cover

Tree targets grew from one million to five million and 20 million

Watch

What was observed
IIED lists an initial goal of one million trees by 2022, then five million by 2030 and 20 million by 2050, and vegetation cover up 50% on 2018 by 2030.
What would confirm or refute it
Independent evidence on tree survival, location and who maintains the trees would show whether the larger targets are tracked.
Source
IIED · Building low-carbon resilience into Freetown’s future (2024-02-14)
Next review
2026-11-06

Christchurch · Planning and land use

Emergency planning powers ended between 2019 and 2021

Observation

What was observed
The Replacement District Plan became operative on 19 December 2017; the 2014 Order was revoked on 18 March 2019 and the Act expired on 30 June 2021.
What would confirm or refute it
Check which temporary permissions and decisions made under the emergency regime remain in force, and who can review them.
Source
Christchurch City Council · The process behind the plan (date not shown)
Next review
2026-11-06

Medellín · Mobility

A four-year development plan approaches its last year

Watch

What was observed
“Medellín Te Quiere” covers 2024–2027. The landing page does not list sector targets; they are in the full PDF.
What would confirm or refute it
Extract the mobility and housing targets from the PDF and compare them with reported delivery by neighbourhood.
Source
Alcaldía de Medellín · Plan de Desarrollo (date not shown)
Next review
2026-11-06

Kigali · Planning and land use

Fewer land-use zones: commercial 9 to 3, residential 7 to 5

Watch

What was observed
The City of Kigali reports a simpler zoning scheme in the Master Plan 2050, published on 4 September 2020.
What would confirm or refute it
Look for how residents can obtain advice and appeal under the simpler scheme, and for evidence on who is affected.
Source
City of Kigali · Master Plan 2050 launch (2020-09-04)
Next review
2026-11-06

Surabaya · Waste

City-level waste targets not located yet

Data gap

What was observed
The library links the city environment department. No quantified city target with a year has been confirmed yet.
What would confirm or refute it
Locate the city’s own waste strategy document and record its numbers, years and definitions.
Source
Surabaya · Dinas Lingkungan Hidup (date not shown)
Next review
2026-11-06

Dhaka · Water

Groundwater decline figures are not reconciled

Data gap

What was observed
A report of 6 April 2026 says about 70% of Dhaka’s water comes from deep tube wells and quotes a former utility chairman on a fall of about one metre a year; it puts the Gandharbpur plant at about 50% complete and Saidabad Phase 3 at about 20%.
What would confirm or refute it
A monitoring series from the utility or the water authority, with well locations and depths, would settle the rate of decline.
Source
The Daily Star · Dhaka Wasa turns to groundwater despite unfinished projects (2026-04-06)
Next review
2026-11-06

Almaty · Emissions

Expected air gains from a plant conversion await measurement

Watch

What was observed
The EBRD states that converting CHP-2 from coal to gas is expected to cut nitrogen-oxide emissions by more than 86% and annual CO2 by 55%, and to remove dust and sulphur oxides. These are expected effects, published in November 2022.
What would confirm or refute it
Station-level measurements of nitrogen dioxide and particulate matter before and after commissioning would confirm or refute the expected effect.
Source
EBRD · EBRD channels €260 million to modernise Almaty CHP 2 (2022-11-25)
Next review
2026-11-06

Nusantara · Planning and land use

A 2028 target meets the pace of relocation

Watch

What was observed
The head of the IKN Authority said in April 2026 that about 2,000 staff were working in Nusantara as of March 2026 and that about 4,000 are targeted by 2028, with legislative and judicial complexes planned for completion by 2027.
What would confirm or refute it
Published staff counts, completed housing and services, and land-cover change after 2024 would show whether the pace matches the target.
Source
ANTARA News · Indonesia pushes Nusantara legislative, judicial projects in 2026 (2026-04-02)
Next review
2026-11-06

Rotterdam · Water

A celebrated water square is described as a mixed success

Observation

What was observed
A 2021 IDOS discussion paper says the Benthemplein water square “has seen mixed success” and sees room for better management and accessibility, alongside its role in community engagement.
What would confirm or refute it
Use counts, maintenance records, flood events and residents’ views over several years would show how the square performs in wet and dry weather.
Source
IDOS (formerly DIE) · Resilience through placemaking: public spaces in Rotterdam’s climate adaptation approach (2021)
Next review
2026-11-06

Lagos · Planning and land use

A 2025 vision year has passed

Watch

What was observed
The 2020 strategy cites a vision that by 2025 Lagos will be Africa’s Model Megacity, and sets out 31 initiatives and sub-actions for resilience. Reports on delivery have not been located yet.
What would confirm or refute it
Progress reports for the initiatives, flood data by neighbourhood and independent accounts from waterfront communities would show what was delivered.
Source
Lagos State Government · Lagos Resilience Strategy (2020)
Next review
2026-11-06

Cape Town · Water

Target year for 300 million litres per day of new water: 2030 in 2022 report, mid-2030s in 2026

Data gap

What was observed
SAnews (4 August 2022) reports that the programme aims to produce approximately 300 million litres per day by 2030. The City's release of 25 September 2026 refers to a target of 300 million litres per day from new sources by the mid-2030s.
What would confirm or refute it
The City's New Water Programme documents or council reports stating the target year and the list of projects counted towards it, with their capacities and dates.
Source
City of Cape Town · City begins procurement for Faure New Water Scheme (news and notices) (2026-09-25)
Next review
2026-11-06

Cape Town · Water

Reported use of 1 025 MLD against a summer target of less than 975 MLD

Observation

What was observed
The City reported that average water usage on 31 December 2025 was 1 025 MLD with dams at 70.5%, against a summer target of less than 975 MLD, and that the main supply dams were 19.2% lower than a year earlier.
What would confirm or refute it
The City's weekly water dashboard or dam-level and consumption reports for the 2025/26 summer, compared week by week with the 975 MLD target.
Source
SAnews (South African Government News Agency) · City of Cape Town urges public to save water (2026-01-02)
Next review
2026-11-06

Singapore · Green cover

Tree target year: 2030 in the Green Plan, end 2027 expected by NParks

Data gap

What was observed
The Green Plan targets page gives 1 million more trees by 2030. NParks stated on 15 April 2023 that it expects to reach the target of one million trees by end 2027, with over 500,000 planted since March 2020. The two documents state different years and the NParks figure is from 2023.
What would confirm or refute it
A current official NParks or Green Plan progress count of trees planted since 2020, with its date and counting method.
Source
NParks · More than half a million trees planted with the community (OneMillionTrees) (2023-04-15)
Next review
2026-11-06

Singapore · Waste

Interim 2026 waste-to-landfill target listed before the 2030 target

Watch

What was observed
The targets page lists an interim aim for 2026 to reduce the amount of waste to landfill per capita per day by 20%, alongside the 30% aim for 2030. The page read for this entry gives no measured value.
What would confirm or refute it
A published national waste statistics report or Green Plan progress report giving landfilled waste per capita per day for 2026 against the stated baseline.
Source
Singapore Green Plan 2030 · Our Targets (2026-03-31)
Next review
2026-11-06

Seoul · Water

Deep rainwater tunnel completion given as 2027 and as 2030 in two sources

Data gap

What was observed
An SMG page dated 2023-05-11 says the three deep rainwater tunnels (Gangnam Station, Dorimcheon, Gwanghwamun) are to be built by 2027. A news report dated 2026-05-11 describes the same three tunnels as scheduled for completion by 2030.
What would confirm or refute it
SMG's current official project schedule or budget documents for the deep underground rainwater drainage tunnels, with dated revisions.
Source
The Asia Business Daily · Expanding "Rainwater Bowls" and Using AI for Prevention... Seoul Steps Up Storm and Flood Preparedness (2026-05-11)
Next review
2026-11-06

Seoul · Mobility

Climate Card usage reported; emissions or modal-shift effects not in the page

Data gap

What was observed
SMG's 2026-01-02 release reports about 720,000 average daily users as of November 2025 and more than 17 million recharge transactions. The page read gives no figures on emissions reduced or on changes in public transport share.
What would confirm or refute it
SMG or Seoul Institute evaluation reports on the Climate Card with before-and-after modal share or emissions estimates.
Source
Seoul Metropolitan Government · Climate Card Marks Two Years, Expands Seoul's Transport Welfare to Model Nationwide (2026-01-02)
Next review
2026-11-06

Copenhagen · Emissions

City reports KBH2025 plan reached about 80 % of the way to climate neutrality

Observation

What was observed
In its press release of 2025-09-18 announcing Climate Strategy 2035, the City of Copenhagen states that the KBH2025 climate plan brought the municipality about 80 % of the way to climate neutrality. The release does not give the underlying emission figures.
What would confirm or refute it
The City's published annual CO2 accounts (Klimaregnskab) for the municipality, compared with the 2025 baseline and boundary defined in the KBH2025 plan.
Source
Københavns Kommune (Klima-, Miljø- og Teknikforvaltningen) · København har vedtaget en ny klimastrategi for de næste 10 år (2025-09-18)
Next review
2026-11-06

Copenhagen · Water

Cloudburst plan: 300 projects planned, 11 % of earmarked funds disbursed by 2022

Data gap

What was observed
Climate-ADAPT (2016) reports 300 planned projects, around 15 a year over the next 20-30 years, at DKK 11 bn at 2015 prices. A 2022 peer-reviewed article reports that only 11% (EUR 0.2 bn) of the EUR 1.8 bn earmarked had been disbursed at the time of writing in 2022. The sources use different price years and do not state a common completion count.
What would confirm or refute it
The city and water utility's published project lists or annual accounts for the Cloudburst Management Plan, showing completed projects and spending per year against the earmarked amount.
Source
Buildings & Cities (Whittaker and Jespersen) · Stretching or conforming? Financing urban climate change adaptation in Copenhagen (2022-11-23)
Next review
2026-11-06

Barcelona · Mobility

Measured NO2 and PM10 change in the Sant Antoni superblock

Observation

What was observed
A BMC Public Health study reported by IDIAP Jordi Gol (February 2025) covers three Barcelona superblocks over 2019-2021 and reports a 25% fall in NO2 and a 17% fall in PM10 in the Sant Antoni superblock.
What would confirm or refute it
Air-quality monitoring series before and after works in the Eixample green axes, using the same stations and method as the 2025 study.
Source
IDIAP Jordi Gol · Barcelona's superblocks improve quality of life and environmental health (BMC Public Health 2025) (2025-02)
Next review
2026-11-06

Vancouver · Mobility

Commuter transit share is published; the plan's trip-based target has no matching figure here

Data gap

What was observed
Statistics Canada (3 February 2025) reports that Vancouver's public transit commuter share was similar to its pre-pandemic level, with 20.5 percent in both May 2016 and May 2024, for commuters aged 15 to 69. The city target concerns all trips by active transportation and transit, a different measure, and no like-for-like trip figure was available in the sources read.
What would confirm or refute it
The city's own trip-based mode share reported for 2023 or later (e.g. its Climate Emergency Action Plan annual report) compared with the 2030 target.
Source
Statistics Canada · From home to work: Commuting in Canada's cities, May 2024 (2025-02-03)
Next review
2026-11-06

Vancouver · Green cover

University study reports barriers to green infrastructure implementation

Observation

What was observed
A Simon Fraser University study (17 July 2024) reports that the city struggles to adopt green infrastructure due to political, organizational, educational, funding, ownership and engagement barriers, and that the city's green infrastructure branch was established in 2016.
What would confirm or refute it
The city's Rain City Strategy implementation reports and green rainwater infrastructure capital budgets for 2024 and later.
Source
Simon Fraser University · Vancouver faces barriers to green infrastructure implementation (2024-07-17)
Next review
2026-11-06

New York City · Emissions

LL97: filing rates reported, compliance with limits not stated in the same release

Data gap

What was observed
The city release dated 22 April 2026 reports that approximately 93% of covered privately owned properties, representing 91% of covered buildings, filed Local Law 97 reports, and that approximately 1,400 properties required to report have not done so. It does not state how many buildings are within their emission limits.
What would confirm or refute it
DOB Local Law 97 compliance report data (filed emissions against limits per building) compared with the filing counts in the release.
Source
NYC Housing Preservation and Development · New Compliance Data Shows Impact of Local Law 97 to Improve Sustainability in New York City (2026-04-22)
Next review
2026-11-06

New York City · Emissions

LL97: stricter emission limits stated to begin in 2030

Watch

What was observed
The Department of Buildings page states that most buildings over 25,000 square feet are required to meet new GHG emissions limits beginning in 2024, with stricter limits coming into effect in 2030.
What would confirm or refute it
DOB-published 2030 limit tables and the first 2030-period compliance reports, compared with 2024-period reported emissions.
Source
NYC Department of Buildings · LL97 Greenhouse Gas Emissions Reductions (2026-03)
Next review
2026-11-06

Bogotá · Mobility

Metro Line 1 works reported at 83.73% overall progress in September 2026

Observation

What was observed
The District Government reports that the Line 1 works completed 83.73% overall progress during September 2026, on 23.9 km of route with 16 stations, and that 20 of the 30 trains are already in Colombia. Commercial operation is planned for March 2028.
What would confirm or refute it
The monthly progress reports of the metro project company for October 2026 onward, and the delivery date of the remaining 10 trains.
Source
Alcaldía de Bogotá · Línea 1 del Metro de Bogotá llegó al 83,73 % de avance en septiembre de 2026 (2026-10-06)
Next review
2026-11-06

Bogotá · Mobility

Different electric-bus renewal figures in sources of different dates

Data gap

What was observed
A District page of June 2025 speaks of renewing 364 buses; a District page of April 2025 speaks of 101 new electric buses arriving; a news report of April 2026 states a renewal totalling 711 vehicles between 2026 and 2027, with a first batch of 68 buses already in circulation.
What would confirm or refute it
The concession contracts and fleet-delivery schedule published by TransMilenio, showing which vehicles belong to each figure and the delivery dates.
Source
Infobae · Nuevos buses eléctricos del SITP que ya operan en Bogotá (2026-04-01)
Next review
2026-11-06

Melbourne · Green cover

Canopy figures reported on different bases (22% in 2019; about 30% per precinct in 2024)

Data gap

What was observed
A 2019 university article says tree canopy covers about 22 per cent of the city's public streets and parks and 3 per cent of the private realm. A 2024 local news article, citing the strategy, says canopy cover for each precinct has not progressed far beyond 30 per cent against the 40 per cent by 2040 aim. The two statements differ in unit (public realm or precinct) and year and are not reconciled in the sources read.
What would confirm or refute it
The city's own canopy statistics for the public realm by year (for example from its aerial-imagery canopy datasets, 2021 and later) and the Urban Forest Strategy progress reporting.
Source
The Melburnian · City of Melbourne unveils next urban forest plan for inner city (2024-07-31)
Next review
2026-11-06

Melbourne · Green cover

City tree register: 82,064 trees; 3,129 with planting year 2024

Observation

What was observed
The open dataset, described as listing the location, species and lifespan of the urban forest by precinct and processed on 2025-09-22, returned a total_count of 82,064 records when queried on 2026-10-07. Filtering the same dataset on year_planted 2024 returned a total_count of 3,129. The city states a planting rate of 3000 trees a year; the register does not by itself show removals or survival.
What would confirm or refute it
Yearly counts of year_planted and of removed or dead trees from the register's later versions, compared with the stated 3000 a year and with the measured canopy cover.
Source
City of Melbourne Open Data Portal · Trees, with species and dimensions (Urban Forest) (2025-09-22)
Next review
2026-11-06

Paris · Planning and land use

Oasis schoolyard counts differ between two city pages

Data gap

What was observed
The oasis page (updated 15 January 2025) reports that since 2017, 203 oasis yards and 5 oasis nurseries have been built. The climate-adaptation page (updated 18 June 2025) gives a figure of 165 oasis yards accessible in schools, colleges and nurseries for summer 2025. The pages do not explain whether the counts use the same definition.
What would confirm or refute it
A dated city list of oasis sites by school (completed, accessible, under construction) from the Ville de Paris open data or a Council deliberation report.
Source
Ville de Paris · Comment Paris s'adapte au changement climatique (2025-06-18)
Next review
2026-11-06

Paris · Water

Seine bathing 2025: Paris sites open about two-thirds of days

Observation

What was observed
The city press release of 5 June 2026 reports that in 2025 the three Paris bathing sites were open on average two-thirds of days in July and August and received close to 100,000 swimmers. The city's water page (updated 19 August 2026) says the Seine is analysed daily for Escherichia coli and enterococci, with ARS monitoring posted at each site.
What would confirm or refute it
The monthly city water-quality bulletins for July-August 2025 and 2026 and the ARS bathing-water results, compared with daily closure notices.
Source
Ville de Paris (presse) · Réouverture des sites de baignade en Île-de-France : 8 sites ouverts pour la saison 2026 (2026-06-05)
Next review
2026-11-06

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City observer protocol

Updated: 2026-10-07. Next review: 2026-11-06. Sources retain their original publication dates.