CGE: São Paulo's rain alerts and street-level flood-point map
São Paulo's city hall has run the CGE since November 1999, after a flood filled the Anhangabaú tunnel. It reads its own automatic weather stations and rain gauges in 32 subprefeituras alongside the state DAEE radar and Alto Tietê telemetry, then declares an estado de atenção or alerta zone by zone. The public flood-point map is not sensed — municipal traffic agents on the street report each alagamento and grade it transitável or intransitável. An alert pre-positions crews and warns drivers; it opens no gate and starts no pump.
A live flood map can look like sensing and not be. São Paulo's alagamento layer is human observation typed in by traffic agents, so its coverage follows the main roads they patrol — and it records water that has already arrived rather than predicting it.
Evidence• No measured figure
Scale🏙️ City-wide
Sources
↗ CGE — Quem somos (Prefeitura de São Paulo)Operator page, fetched 2026-07-26. Carries the founding sentence — "criado em novembro de 1999" — the link to the Secretaria Municipal de Infraestrutura Urbana e Obras (SIURB), the list of bodies it feeds (Defesa Civil, CET, Corpo de Bombeiros, subprefeituras) and the Plano Preventivo Chuvas de Verão.
↗ CGE — Classificação dos alagamentosThe load-bearing source for the entry's spine. States that flood information "são fornecidas pelos agentes de campo (trânsito) da Prefeitura de São Paulo", defines transitável and intransitável verbatim, and concedes that collection concentrates on major thoroughfares.
↗ CGE — Fontes de informaçãoThe city's own statement of what it owns versus consumes: the radar is "operado pela FCTH… de propriedade do DAEE" (state), the telemetric network covers "aproximadamente 300 pontos da bacia do Alto-Tietê" (state), while the automatic weather stations are the CGE's and the conventional rain gauges are the Prefeitura's, read four times a day by Defesa Civil agents.
↗ CGE — MonitoramentoNames the rain gauges in 32 subprefeituras, the SAISP radar at Salesópolis as the primary radar, and auxiliary radars from the Air Force, Unesp, CPTEC/INPE and Simepar.
↗ SAISP — Rede Telemétrica do Alto Tietê (DAEE/FCTH)State system, included only to mark the boundary: SAISP's radar and ~300 telemetry points are what the municipal CGE consumes. Content confirmed via search results and via the CGE's own fontes page rather than a direct fetch.
↗ Agência SP — "De onde vêm os alertas da Defesa Civil? Conheça o CGE" (Feb 2025)Disambiguation source. The STATE Defesa Civil opened its own Centro de Gerenciamento de Emergências at the Palácio dos Bandeirantes on 13 Feb 2025 (R$47.1M with the Cepram radar centre); the cellphone alerts come from there, not from the municipal CGE. Two different bodies sharing an acronym — deliberately not merged into this entry.
↗ CartaCapital — driver killed in a São Paulo flood, 2 Feb 2025Counterweight. On 1 Feb 2025 an app driver died on Rua Prece, Vila Prudente, after his car stalled crossing standing water. Verified at search-snippet level across four outlets (CartaCapital, Jovem Pan, Terra, Diário do Grande ABC); direct fetch not attempted. The accompanying "18th victim" figure is a STATE Defesa Civil count for the whole state since December, not a city figure, and is therefore not used in the entry.
↗ Agência Brasil — storms put the city of São Paulo on alert (Jan 2026)Currency check: CGE-declared alert states and named flood points reported in January 2026, with further CGE attention states in June 2026. Agência Brasil served automated fetches an electoral-legislation placeholder page, so this is verified at search-result level.
1001 Smart Cities (2026). “CGE: São Paulo's rain alerts and street-level flood-point map” — São Paulo, Brazil. The Smart City Atlas. https://1001smartcities.org/projects/sao-paulo-cge-flood-alert/ (last verified 2026-07-26). Data: CC BY 4.0.
The underlying data is free to reuse with attribution — see the open data page.
