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pricing works, plus rates and operating hours.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-48f6af84a5cf3c53", "title": "Ministry of Transport (authority)", "url": "https://www.mot.gov.sg/what-we-do/motoring-road-network-and-infrastructure/Electronic-Road-Pricing/Details/how-erp-works-as-a-speed-booster", "publisher": { "name": null, "domain": "mot.gov.sg", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "background", "claimRefs": [], "temporal": { "publishedAt": "2022-03-21", "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-20", "retrievedAt": null, "status": "publication-and-record-dates-recorded" }, "locator": { "type": "descriptive-source-note", "value": "Explains the 45-65 km/h expressway (and 20-30 km/h arterial) optimal-speed bands ERP targets.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-feba385911a727f1", "title": "Wikipedia — Electronic Road Pricing", "url": "https://en.wikipedia.org/wiki/Electronic_Road_Pricing", "publisher": { "name": null, "domain": "en.wikipedia.org", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "background", "claimRefs": [], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-20", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "Encyclopedia article with the full timeline of ERP and ALS.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-10df15aa074fd521", "title": "MAJU (research)", "url": 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"ink.library.smu.edu.sg", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-0d32f1c608d40829" ], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-20", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "Independent academic evaluation: the 1998 ERP cut charging-zone traffic ~10–15% and raised speeds ~30%.", "exact": false }, "preservation": { "archiveUrl": "https://web.archive.org/web/20260518070922/https://ink.library.smu.edu.sg/soe_research/117", "archivedAt": "2026-05-18", "contentHash": null, "status": "archive-linked" } } ], "coverage": { "claimsTotal": 1, "claimsMapped": 1, "sourcesTotal": 5, "sourcesUsedByClaims": 1, "sourcesWithPublicationDate": 3, "sourcesWithArchive": 1, "sourcesWithExactLocator": 0, "sourcesWithContentHash": 0 }, "limits": [ 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This revision has not been reviewed by a human or subject-matter expert.", "machineChecks": [ "schema", "publication-diff-contract", "material-project-fingerprint", "claim-text-drift", "source-reference-resolution", "complete-source-dossier", "snapshot-hash" ] }, "projectState": { "status": "live", "outcome": "succeeded", "evidenceGrade": "peer-reviewed", "timeline": { "started": 1998, "ended": null } }, "governance": { "operator": "Land Transport Authority (LTA)", "actorTypes": [ "utility" ], "fundingModel": "public", "fundingDescription": null, "cost": null, "ownership": null, "decisionRights": null, "exitConditions": null }, "claims": [ { "id": "clm-6d9a727bafb096e5", "field": "snippet", "text": "Since replacing the Area Licensing Scheme in 1998", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-48f6af84a5cf3c53", "src-feba385911a727f1" ], "supportNote": "The Ministry of Transport dates the handover directly: \"In 1998, this was replaced by the ERP system, which leverages on technology to allow for a more effective and flexible method of congestion charging.\" Wikipedia gives the operator and the exact day for the first stage: \"The ERP was implemented by the Land Transport Authority (LTA) on 1 April 1998 to replace the preceding Singapore Area Licensing Scheme (ALS).\"", "caveat": "The changeover ran in stages during 1998 rather than on a single day: the expressway charging came first in April, and the central Restricted Zone cordon followed in September.", "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-27b01870ca60d6fc", "field": "snippet", "text": "Singapore's ERP has used gantry tolling", "statementKind": "descriptive", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-2cc265e96c0289f1" ], "supportNote": "The operator's own ERP page describes exactly this mechanism: \"You pay a fee when driving through an ERP gantry during operational hours\", and \"The In-vehicle Unit (IU) in your vehicle deducts the ERP charges based on your chosen mode of payment.\"", "caveat": null, "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-d73db5c5865986e0", "field": "snippet", "text": "to keep expressway speeds in a 45-65 km/h target band", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-48f6af84a5cf3c53" ], "supportNote": "The Ministry of Transport names the band and the rule attached to it: \"The optimal traffic speed range is 45 - 65 km/h on expressways and 20 - 30 km/h on arterial roads\", and \"ERP rates will be increased if traffic moves slower than 45 km/h on expressways and 20 km/h on roads.\"", "caveat": "The Ministry describes the band as it stands today and does not say it has governed rate-setting continuously since 1998.", "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-75d77fbbba5528e1", "field": "snippet", "text": "A satellite-based ERP 2.0", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-10df15aa074fd521", "src-feba385911a727f1" ], "supportNote": "MAJU: \"From 1 January 2027, Singapore will fully implement its new satellite-based ERP 2.0 system.\" Wikipedia names the technology: \"The ERP 2.0 system is a Global Navigation Satellite System (GNSS) based system, as opposed to the current system with physical gantries.\"", "caveat": null, "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-6621040cf82da6f6", "field": "snippet", "text": "with on-board units fitted since November 2023", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-feba385911a727f1", "src-10df15aa074fd521" ], "supportNote": "Wikipedia: \"Installation of the OBU started in November 2023.\" MAJU repeats the start date and adds the count reached: \"Since installation began in November 2023\", and \"As of 31 January 2026, approximately 930,000 vehicles (representing more than 93 per cent of all vehicles in Singapore) have been fitted with an OBU.\"", "caveat": null, "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-b803923f131cf74f", "field": "snippet", "text": "takes over charging in full from 1 January 2027", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-10df15aa074fd521", "src-59c9011cf515565c" ], "supportNote": "MAJU dates the full switch to the satellite system to 1 January 2027, and the operator's own ERP 2.0 page describes the replacement as \"Global Navigation Satellite System (GNSS) based\" and working \"without bulky gantries\". Neither source says the gantries are physically gone on that date — their removal is described as a separate exercise that follows.", "caveat": "The date is the switch-over of charging, not the removal of the roadside gantries.", "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-ebfb808655a26f4b", "field": "snippet", "text": "initially keeping the same location-based charges", "statementKind": "descriptive", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-feba385911a727f1" ], "supportNote": "Wikipedia: \"The current ERP charges will remain the same, with the OBUs able to work the same as the IUs when passing through a physical ERP gantry.\"", "caveat": "MAJU describes the new unit measuring a vehicle against virtual charging zones rather than fixed gantry points, so charges stay tied to places but the places need no longer be a gantry.", "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-f4ceab6f40d5809f", "field": "snippet", "text": "distance-based pricing remains a future option", "statementKind": "descriptive", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-feba385911a727f1", "src-10df15aa074fd521" ], "supportNote": "Wikipedia: \"LTA announced that the distance-based charging policy will not be implemented in the near future, with no concrete date on when the new policy will take place.\" MAJU says the same from the government side: \"the Government has clarified that it has no immediate plans to implement distance-based charging\".", "caveat": null, "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-83faa973730a7c47", "field": "impact", "text": "After Singapore's 1998 ERP launch", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-48f6af84a5cf3c53", "src-feba385911a727f1" ], "supportNote": "The Ministry of Transport dates the launch to 1998: \"In 1998, this was replaced by the ERP system.\" Wikipedia gives the first operating day: \"The ERP was implemented by the Land Transport Authority (LTA) on 1 April 1998.\"", "caveat": null, "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-0d32f1c608d40829", "field": "impact", "text": "traffic volume in the charging zone fell roughly 10–15% against the Area Licensing Scheme baseline", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-82e136f3f6d6249a", "src-b217df300ec7d344" ], "supportNote": "The International Transport Forum paper carries the figure and names where it comes from: \"Traffic entering the RZ fell by 10-15% relative to the ALS\", attributed to Chin (2002) and Phang and Toh (2004). The Phang and Toh article itself could not be read — the repository page answers automated requests with a bot-protection wall — so the figure rests here on the ITF review's account of it.", "caveat": "The published abstract of the paper describes a review of 28 years of congestion pricing and does not itself carry this percentage, so the attribution rests on later work citing it. The reduction is also read as an effect of switching from a multiple-entry day licence to a per-passage charge, not of a higher price: charges were lowered at the changeover.", "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-73a0dc1bbc8202ef", "field": "impact", "text": "expressway speeds during charging hours rose from 35 to 55 km/h", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-1ec0494003c889b1" ], "supportNote": "The measured figure the entry lacked: \"The initial traffic monitoring showed that traffic volumes on the expressways reduced by 15% and speeds increased from 35 to 55 kph during the ERP hours.\"", "caveat": "The lead author was previously the Land Transport Authority's chief transportation engineer, so this is an insider's academic account of the scheme's early monitoring rather than an outside evaluation of it.", "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-be7dba6a403e846c", "field": "impact", "text": "rates are adjusted to hold expressway speeds in a 45–65 km/h target band", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-48f6af84a5cf3c53", "src-2cc265e96c0289f1" ], "supportNote": "The Ministry of Transport states both the band and the adjustment rule: \"If traffic speeds rise above 65 km/h on expressways and 30 km/h on roads, ERP charges at that gantry will be reduced. Conversely, ERP rates will be increased if traffic moves slower than 45 km/h on expressways and 20 km/h on roads.\" The operator gives the cadence: \"ERP rates are reviewed every quarter and adjusted during the June and December school holidays, based on the traffic conditions at the time.\"", "caveat": null, "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } } ], "sources": [ { "id": "src-2cc265e96c0289f1", "title": "Land Transport Authority (authority)", "url": "https://onemotoring.lta.gov.sg/content/onemotoring/home/driving/ERP/ERP.html", "publisher": { "name": null, "domain": "onemotoring.lta.gov.sg", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-27b01870ca60d6fc", "clm-be7dba6a403e846c" ], "temporal": { "publishedAt": null, "updatedAt": "2026-06-24", "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-23", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "Official ERP page: how gantry-based RFID road pricing works, plus rates and operating hours.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-48f6af84a5cf3c53", "title": "Ministry of Transport (authority)", "url": "https://www.mot.gov.sg/what-we-do/motoring-road-network-and-infrastructure/Electronic-Road-Pricing/Details/how-erp-works-as-a-speed-booster", "publisher": { "name": null, "domain": "mot.gov.sg", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-6d9a727bafb096e5", "clm-d73db5c5865986e0", "clm-83faa973730a7c47", "clm-be7dba6a403e846c" ], "temporal": { "publishedAt": "2022-03-21", "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-23", "retrievedAt": null, "status": "publication-and-record-dates-recorded" }, "locator": { "type": "descriptive-source-note", "value": "Explains the 45-65 km/h expressway (and 20-30 km/h arterial) optimal-speed bands ERP targets.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-feba385911a727f1", "title": "Wikipedia — Electronic Road Pricing", "url": "https://en.wikipedia.org/wiki/Electronic_Road_Pricing", "publisher": { "name": null, "domain": "en.wikipedia.org", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-6d9a727bafb096e5", "clm-75d77fbbba5528e1", "clm-6621040cf82da6f6", "clm-ebfb808655a26f4b", "clm-f4ceab6f40d5809f", "clm-83faa973730a7c47" ], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-23", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "Encyclopedia article with the full timeline of ERP and ALS.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-10df15aa074fd521", "title": "MAJU (research)", "url": "https://www.maju.sg/post/from-gantries-to-satellites-the-erp-2-0-system", "publisher": { "name": null, "domain": "maju.sg", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-75d77fbbba5528e1", "clm-6621040cf82da6f6", "clm-b803923f131cf74f", "clm-f4ceab6f40d5809f" ], "temporal": { "publishedAt": "2026-06-03", "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-23", "retrievedAt": null, "status": 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evaluation of Singapore's road pricing from 1975 to 2003, and the origin of the 10–15% traffic figure. The repository page refuses automated requests, so the article text could not be read here; the indexed abstract carries no percentages, and the \"~30%\" speed figure this note used to claim appears in no published account of the scheme.", "exact": false }, "preservation": { "archiveUrl": "https://web.archive.org/web/20260518070922/https://ink.library.smu.edu.sg/soe_research/117", "archivedAt": "2026-05-18", "contentHash": null, "status": "archive-linked" } }, { "id": "src-b217df300ec7d344", "title": "Theseira, ITF/OECD Discussion Paper 2020/10 (independent)", "url": "https://www.oecd.org/content/dam/oecd/en/publications/reports/2020/10/congestion-control-in-singapore_c3005a82/7d266609-en.pdf", "publisher": { "name": null, "domain": "oecd.org", "classification": "not-classified" }, "sourceType": "pdf", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-0d32f1c608d40829" ], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-23", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "International Transport Forum roundtable paper by Walter Theseira. Attributes the 10–15% reduction in the Restricted Zone to Chin 2002 and Phang and Toh 2004, and explains it as an effect of switching from a multiple-entry licence to a per-passage charge — achieved even though the tolls themselves were lowered. It carries no speed-increase percentage.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-59c9011cf515565c", "title": "Land Transport Authority — ERP 2.0 (authority)", "url": "https://onemotoring.lta.gov.sg/content/onemotoring/home/driving/ERP/erp-2-0.html", "publisher": { "name": null, "domain": "onemotoring.lta.gov.sg", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-b803923f131cf74f" ], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-23", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "The operator's own page for the transition: the replacement is \"Global Navigation Satellite System (GNSS) based\" and works \"without bulky gantries\", on-board unit installation \"has started since November 2023\", \"The current form of congestion pricing will continue for now\", and \"There are no immediate plans to impose distance-based road pricing.\"", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-1ec0494003c889b1", "title": "Menon & Guttikunda, SIM-air Working Paper 33-2010 (independent)", "url": "https://urbanemissions.info/wp-content/uploads/docs/SIM-33-2010.pdf", "publisher": { "name": null, "domain": "urbanemissions.info", "classification": "not-classified" }, "sourceType": "pdf", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-73a0dc1bbc8202ef" ], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-17", "dossierCreatedAt": "2026-08-23", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "Academic account of ERP with the first-year measurements: \"The initial traffic monitoring showed that traffic volumes on the expressways reduced by 15% and speeds increased from 35 to 55 kph during the ERP hours\", and the speed targets as standing policy. Read with the authorship in mind — the lead author is a former chief transportation engineer at the LTA, so this is an insider's academic account rather than an outside audit.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } } ], "coverage": { "claimsTotal": 12, "claimsMapped": 12, "sourcesTotal": 8, "sourcesUsedByClaims": 8, "sourcesWithPublicationDate": 2, "sourcesWithArchive": 1, "sourcesWithExactLocator": 0, "sourcesWithContentHash": 0 }, "limits": [ "Publisher names and source languages have not yet been classified; domains are recorded without guessing.", "Existing source notes are descriptive locators, not page- or paragraph-exact citations.", "A missing archive, publication date or content hash is shown as null rather than inferred.", "The project-level evidence grade ranks the strongest source in the entry; it is not a truth score for every claim." ] } } ] }