{
 "schemaVersion": "1.0.0",
 "constitutionVersion": "1.0.0",
 "createdAt": "2026-08-12T00:00:00Z",
 "description": "Append-only Evidence Passport records. Old revisions are immutable; corrections create a new revision and preserve the previous permalink.",
 "entity": {
  "type": "project",
  "id": "washington-dc-clean-rivers-tunnels",
  "title": "DC Water's Clean Rivers Tunnels & the Consent Decree Behind Them",
  "canonicalUrl": "https://1001smartcities.org/projects/washington-dc-clean-rivers-tunnels/"
 },
 "currentRevisionId": "2026-08-21-source-dates",
 "revisions": [
  {
   "id": "2026-08-20-claim-baseline",
   "createdAt": "2026-08-21T13:45:00Z",
   "effectiveAt": "2026-07-26",
   "changeType": "baseline",
   "summary": "Created the first structured Evidence Passport with 12 claims and 12 source dossiers.",
   "preparedBy": {
    "type": "automation",
    "label": "AI-assisted evidence preparation",
    "humanApproved": false
   },
   "review": {
    "status": "unreviewed",
    "by": null,
    "date": null,
    "note": "Awaiting operator and domain-expert review; publication of this revision implies neither."
   },
   "changes": [
    {
     "operation": "add",
     "path": "/evidencePassport",
     "summary": "Added claim-level evidence mapping and source dossiers."
    },
    {
     "operation": "add",
     "path": "/revisionHistory",
     "summary": "Established a permanent, hash-addressed baseline revision."
    }
   ],
   "snapshotHash": "sha256:c714871c7a1ad21ba4527283a128354da6a84455d165af760e19f815f8d9637b",
   "snapshot": {
    "asOf": "2026-07-26",
    "projectFingerprint": "sha256:5df5c05b88b60e1237bcd0c53ffb39e3c0c9a5342175e9af52f97c8d8187ef19",
    "assurance": {
     "status": "unreviewed",
     "scope": "evidence-passport-revision",
     "statement": "AI-assisted structural preparation. 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": "ongoing",
     "evidenceGrade": "official",
     "timeline": {
      "started": 2005,
      "ended": null
     }
    },
    "governance": {
     "operator": "DC Water (District of Columbia Water and Sewer Authority)",
     "actorTypes": [
      "utility"
     ],
     "fundingModel": "utility",
     "fundingDescription": "DC Water ratepayers through the Clean Rivers Impervious Area Charge — $24.23 per equivalent residential unit per month in FY2026, billed by measured impervious cover rather than water use",
     "cost": "≈$3.5bn, estimated at $2.6bn when the decree was signed in 2005",
     "ownership": null,
     "decisionRights": null,
     "exitConditions": null
    },
    "claims": [
     {
      "id": "clm-b23220304e86eb51",
      "field": "snippet",
      "text": "A 2005 federal consent decree with the EPA, the Justice Department and the District — not the utility's own choice — obliges DC Water to end combined sewer overflows",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-a2c555c8759fa950",
       "src-a5558be96eac7cd7"
      ],
      "supportNote": "The regulator's settlement page records a 2005 federal consent decree among EPA, the Department of Justice, the District of Columbia and DC Water, requiring storage tunnels in the Anacostia, Potomac and Rock Creek watersheds, with a $250,000 penalty plus $1.7m for rain gardens and low-impact development and $300,000 to the Chesapeake Bay Foundation. Independent press still describes the programme's 2030 completion date as 'the date set by a consent decree between the federal government, D.C. government and D.C. Water'.",
      "caveat": "The decree sets reduction targets rather than literal elimination: 98% of overflows eliminated in the Anacostia, 93% Potomac, 90% Rock Creek.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-baaab8a5b1098943",
      "field": "snippet",
      "text": "Three deep tunnels are in service",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-8d4c06a323f4cfab",
       "src-7da3e77dad5ac178",
       "src-8ca2e3ab4569ecee"
      ],
      "supportNote": "The programme page describes 'over 18 miles of tunnels' more than 100 feet below ground, draining to Blue Plains. The Anacostia River Tunnel entered service in March 2018; the Northeast Boundary Tunnel followed on 15 September 2023; the Piney Branch groundbreaking of 9 July 2026 is described as the programme's final major tunnel, with the Potomac Tunnel still being bored.",
      "caveat": "No single source states the count. Three is the entry's own tally of tunnels in service at the time of writing, from the individual project pages.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-22e9952a1237f49b",
      "field": "snippet",
      "text": "Twenty-two flow-metering stations and a calibrated sewer model produce the quarterly overflow accounting the decree demands",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-f89994afefe31af6",
       "src-124450ba0dbb1e87"
      ],
      "supportNote": "The collection-system page lists '22 flow-metering stations' across roughly 1,800 miles of sanitary and combined sewers. The combined-sewer page describes the accounting: 'DC Water uses a combination of flow meters and a computer model of the combined sewer system to measure and/or estimate the actual CSOs that have occurred on a quarterly basis', published as quarterly operation reports and consent-decree quarterly reports.",
      "caveat": "The operator says 'computer model'. That it is calibrated is the entry's characterisation, not the operator's word.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-a4ad12ae2461c056",
      "field": "snippet",
      "text": "while inflatable dams, dynamically controlled weirs and outfall gates steer the flow",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-f89994afefe31af6"
      ],
      "supportNote": "The operator states that the system is regulated by 'inflatable dams, dynamically controlled weirs, outfall gates and other flow regulating devices', alongside nine wastewater pumping stations and some 75,000 catch basins and manholes. This actuation layer is why the entry treats the tunnels as more than civil engineering.",
      "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-fc8bf4881ef9df05",
      "field": "snippet",
      "text": "Every District property pays by impervious area",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-218e78bd0aa21fa4",
       "src-7252e6f2161d35bd"
      ],
      "supportNote": "The charge is levied on impervious area rather than on water consumed, at $24.23 per equivalent residential unit per month from 1 October 2025, across six tiers from 0.6 ERU at $14.54 to 13.5 ERU at $327.11. An ERU is 'a statistical median of the amount of impervious surface area in a single-family residential property, measured in square feet'.",
      "caveat": "Measuring by satellite has a political cost the press records: a councilmember objected that 'a picture from a satellite doesn't capture that very well, which puts the onus back on the homeowner', and churches and nonprofits called the charge a heavy burden, prompting council relief programmes.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-a3b82e9cb3687273",
      "field": "impact",
      "text": "DC Water reports the Anacostia River Tunnel kept about 4.5 billion gallons of sewage out of the river in 2018 alone, its first year",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-18cc5d172d1d6dd1"
      ],
      "supportNote": "The figure is carried in the operator's release title and matched by independent WJLA coverage under the same number.",
      "caveat": "A finer figure — 4.57 billion gallons and nearly 900 tons of trash and solids for March to 31 December 2018 — appeared in search results but was not read on a rendered page, so the entry rounds rather than quoting it.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-9efab099491aa0fa",
      "field": "impact",
      "text": "that overflows to the Anacostia are down roughly 90% since it opened in March 2018",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-7da3e77dad5ac178"
      ],
      "supportNote": "The project page states that 'combined sewer overflows to the Anacostia River have been reduced by 90 percent' since completion in March 2018. The tunnel is about 12,500 feet long, 23 feet in diameter, 80 to 120 feet deep.",
      "caveat": "This is the utility's own reporting of its own reduction, computed from the quarterly meter-plus-model accounting rather than an independent measurement.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-df494bf167c99772",
      "field": "impact",
      "text": "DC Water expects 98% for the Anacostia and 96% system-wide, and puts the chance of flooding in Northeast in an average rainfall year at 7%, down from 50%",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-8d4c06a323f4cfab",
       "src-a2c555c8759fa950"
      ],
      "supportNote": "The programme page states targets of 96% system-wide overflow reduction, 98% Anacostia, 93% Potomac and 90% Rock Creek, and chronic flooding risk in Northeast cut 'from 50% to 7%'. The same reduction percentages appear as the decree's expected outcomes on the regulator's settlement page.",
      "caveat": "These are targets, not measurements, and the entry treats them as such.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-72340765c972c797",
      "field": "impact",
      "text": "All figures are the utility's own; the decree's compliance accounting is quarterly, from flow meters plus a model, not a live public measurement",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-124450ba0dbb1e87"
      ],
      "supportNote": "The only real-time public signal the operator describes is a warning light: 'DC Water has installed a series of CSO Event Indicator Lights to notify river users of CSO events' — red during an active overflow, yellow for 24 hours afterwards. Everything else is quarterly, from meters and a model.",
      "caveat": "No predictive or real-time control of the tunnel system is described anywhere on the operator's site, and the entry claims none.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-1b953d87e7837116",
      "field": "lesson",
      "text": "The 2015-16 modification let green infrastructure try to replace concrete in Rock Creek and shrink the Potomac tunnel",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-fa917666e2605d06"
      ],
      "supportNote": "The modification proposed 'Using green infrastructure to retain the first 1.2 inches of rainwater on 365 acres in the Rock Creek area and 133 acres in the Potomac watershed', potentially 'eliminating the Rock Creek storage tunnel and significantly decreasing the size of the Potomac tunnel', in exchange for five more years in those two watersheds. The Anacostia stayed on schedule.",
      "caveat": "The regulator announced the proposal in May 2015; the operator dates the signed modification to 14 January 2016, which is why the entry gives a span rather than a single year.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-21486f455bb5688b",
      "field": "lesson",
      "text": "DC Water assessed it, then broke ground on the Piney Branch Tunnel in July 2026 as the programme's final major tunnel",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-8ca2e3ab4569ecee"
      ],
      "supportNote": "Groundbreaking was on 9 July 2026 for 'about a half-mile, 22-foot wide tunnel deep underground' holding 'at least 4.2 million gallons', due 'by the end of 2029', cutting Piney Branch overflow volume by 96% and frequency from about 25 times a year to about once. The 2015-16 modification had contemplated green infrastructure replacing a 9.5-million-gallon Rock Creek storage facility; the tunnel is being built.",
      "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-c8b0ac763506ce39",
      "field": "lesson",
      "text": "the tunnels intercept combined sewage, not failing pipes or illicit connections",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-8c5df9904b922cd8"
      ],
      "supportNote": "A single outlet, reading the District's own water quality reports to the EPA, puts the upper Anacostia out of compliance for E. coli about 92% of the time against under 40% before the tunnel, and attributes the gap to failing sewer pipes and illicit discharges rather than to combined sewer overflows.",
      "caveat": "Deliberately kept out of the snippet and impact. The underlying environment-department reports were not reached, no operator response is included, and the Anacostia Watershed Society's 2025 report card gave sample year 2024 a passing grade, its second highest since 2014. The claim carried here is the structural one — what the tunnels are built to catch — not the outlet's compliance figure.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     }
    ],
    "sources": [
     {
      "id": "src-a2c555c8759fa950",
      "title": "US EPA — District of Columbia Water and Sewer Authority Clean Water settlement (regulator)",
      "url": "https://www.epa.gov/enforcement/district-columbia-water-and-sewer-authority-district-columbia-clean-water-settlement",
      "publisher": {
       "name": null,
       "domain": "epa.gov",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-b23220304e86eb51",
       "clm-df494bf167c99772"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The decree itself, sentence-level: a 2005 federal consent decree among EPA, the Department of Justice, the District of Columbia and DC Water, requiring storage tunnels in the Anacostia, Potomac and Rock Creek watersheds. Penalty $250,000, plus $1.7m for rain gardens and low-impact development and $300,000 to the Chesapeake Bay Foundation for green roofs. Anacostia work due 2025, Potomac and Rock Creek extended to 2030. Expected outcomes stated as 98% of CSOs eliminated in the Anacostia, 93% Potomac, 90% Rock Creek.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-fa917666e2605d06",
      "title": "US Department of Justice — strategy to reduce the District's sewer overflows will include green infrastructure, 20 May 2015 (regulator)",
      "url": "https://www.justice.gov/archives/opa/pr/strategy-reduce-district-columbia-s-sewer-overflows-will-include-green-infrastructure",
      "publisher": {
       "name": null,
       "domain": "justice.gov",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-1b953d87e7837116"
      ],
      "temporal": {
       "publishedAt": "2015-05-20",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The modification, sentence-level: 'Using green infrastructure to retain the first 1.2 inches of rainwater on 365 acres in the Rock Creek area and 133 acres in the Potomac watershed', potentially 'eliminating the Rock Creek storage tunnel and significantly decreasing the size of the Potomac tunnel', in exchange for 'an additional five years to complete implementation in the Potomac and Rock Creek watersheds'. The Anacostia system stayed on schedule: 'Major portions of this tunnel system are scheduled for completed and in operation in 2018.' DOJ announced the proposal in May 2015; DC Water dates the signed modification to 14 January 2016.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-f89994afefe31af6",
      "title": "DC Water — Wastewater Collection (operator; the actuation and metering layer)",
      "url": "https://www.dcwater.com/about-dc-water/what-we-do/wastewater-collection",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-22e9952a1237f49b",
       "clm-a4ad12ae2461c056"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The reason this is an atlas entry and not only civil engineering, sentence-level: the system includes '22 flow-metering stations' and is regulated by 'inflatable dams, dynamically controlled weirs, outfall gates and other flow regulating devices', alongside '9 wastewater pumping stations', 'approximately 1,800 miles of sanitary and combined sewers' and '75,000 catch basins and manholes'.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-124450ba0dbb1e87",
      "title": "DC Water — Combined Sewer System (operator; the measurement and notification layer)",
      "url": "https://www.dcwater.com/about-dc-water/what-we-do/wastewater-collection/css",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-22e9952a1237f49b",
       "clm-72340765c972c797"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "How overflows are counted, sentence-level: 'DC Water uses a combination of flow meters and a computer model of the combined sewer system to measure and/or estimate the actual CSOs that have occurred on a quarterly basis', published as CSO Division Quarterly Operation Reports and Long Term Control Plan Consent Decree Quarterly Reports. The only real-time public signal: 'DC Water has installed a series of CSO Event Indicator Lights to notify river users of CSO events' — red for an active overflow, yellow for 24 hours afterwards. No predictive or real-time control of the tunnel system is described anywhere on DC Water's site, and the entry claims none.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-8d4c06a323f4cfab",
      "title": "DC Water — Clean Rivers Project (operator)",
      "url": "https://www.dcwater.com/cleanrivers",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-baaab8a5b1098943",
       "clm-df494bf167c99772"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Programme scope and targets, sentence-level: 'over 18 miles of tunnels' more than 100 feet below ground, fed by diversion chambers, approach channels, roughly 100-foot drop shafts and adits, all draining to Blue Plains. Targets stated as 96% system-wide CSO reduction, 98% Anacostia, 93% Potomac, 90% Rock Creek, and chronic flooding risk in Northeast cut 'from 50% to 7%'. The page lists a 2016 amended consent decree and a 2020 joint stipulation of non-material modification. These are targets, not measurements — the entry treats them as such.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-7da3e77dad5ac178",
      "title": "DC Water — Anacostia River Tunnel Project (operator)",
      "url": "https://www.dcwater.com/projects/anacostia-river-tunnel-project",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-baaab8a5b1098943",
       "clm-9efab099491aa0fa"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The 90% figure and its owner, sentence-level: 'combined sewer overflows to the Anacostia River have been reduced by 90 percent' since completion in March 2018. Tunnel is 'approximately 12,500 feet', '23-foot diameter', 'approximately 80 to 120 feet deep'. The page mentions diversion facilities and 'ventilation control facilities to regulate air flow' but no gates, pumping or monitoring detail — so the control layer is sourced from the collection-system pages instead.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-18cc5d172d1d6dd1",
      "title": "DC Water — Anacostia River Tunnel saves river from 4.5 billion gallons of sewage overflow in 2018 (operator)",
      "url": "https://www.dcwater.com/about-dc-water/media/news/dc-waters-anacostia-river-tunnel-saves-river-45-billion-gallons-sewage",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-a3b82e9cb3687273"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "First-year volume, carried in the release title and matched by independent WJLA coverage under the same figure. Search results also gave 4.57 billion gallons and nearly 900 tons of trash and solids for March to 31 December 2018, but that sentence was not read on a rendered page, so the entry rounds to 'about 4.5 billion gallons' rather than quoting the finer number.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-8ca2e3ab4569ecee",
      "title": "DC Water — breaks ground on Piney Branch Tunnel, final phase of the Clean Rivers Project (operator)",
      "url": "https://www.dcwater.com/about-dc-water/media/news/dc-water-breaks-ground-piney-branch-tunnel-final-phase-dc-clean-rivers",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-baaab8a5b1098943",
       "clm-21486f455bb5688b"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The lesson's evidence, sentence-level: groundbreaking 9 July 2026 on 'about a half-mile, 22-foot wide tunnel deep underground' holding 'at least 4.2 million gallons', finished 'by the end of 2029', cutting Piney Branch overflow volume by 96% and frequency from about 25 times a year to about once. The 2015-16 modification had contemplated green infrastructure replacing a 9.5-million-gallon Rock Creek storage facility; the tunnel is being built.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-218e78bd0aa21fa4",
      "title": "DC Water — Clean Rivers Impervious Area Charge rates (operator)",
      "url": "https://www.dcwater.com/customer-center/rates-and-fees/impervious-area-charge",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-fc8bf4881ef9df05"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The financing mechanism, exactly: $24.23 per equivalent residential unit per month effective 1 October 2025 (FY2026). An ERU is 'a statistical median of the amount of impervious surface area in a single-family residential property, measured in square feet'. Six tiers, from 0.6 ERU at $14.54 a month for 100-699 sq ft of impervious cover to 13.5 ERU at $327.11 for 11,100 sq ft and above. The charge is levied on impervious area, not on water consumed.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-7252e6f2161d35bd",
      "title": "51st News — your DC Water bill could get more expensive, January 2026 (press)",
      "url": "https://51st.news/your-dc-water-bill-could-get-more-expensive/",
      "publisher": {
       "name": null,
       "domain": "51st.news",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-fc8bf4881ef9df05"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Cost and the political counterweight: 'a multi-year $3.5 billion infrastructure project kicked off in 2009', construction wrapping up in 2030, 'each ERU now costs homeowners around $24 a month', projected to 'top out at more than $32 per ERU per month' by 2030. Ward 6 Councilmember Charles Allen on the satellite-measured billing: 'a picture from a satellite doesn't capture that very well, which puts the onus back on the homeowner.' Churches and nonprofits called the charge 'a heavy burden', prompting council relief programmes.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-a5558be96eac7cd7",
      "title": "WTOP — DC Water takes big step forward in Potomac River Tunnel project, January 2026 (press)",
      "url": "https://wtop.com/dc/2026/01/dc-water-takes-big-step-forward-in-potomac-river-tunnel-project/",
      "publisher": {
       "name": null,
       "domain": "wtop.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-b23220304e86eb51"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Current construction status: the cutterhead for TBM Mary lowered down a 100-foot shaft at West Potomac Park, tunnelling to start spring 2026 on the 5.5-mile run from the Georgetown waterfront to Blue Plains, with a second machine, Emily, for the 3.1-mile southern segment. Substantial completion expected 2028, full completion February 2030, 'the date set by a consent decree between the federal government, D.C. government and D.C. Water'. Read via search summary rather than a rendered page; the 2030 decree deadline is independently confirmed by the EPA settlement page.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-8c5df9904b922cd8",
      "title": "Investigative Economics — despite massive tunnel project, Anacostia still filled with fecal matter, 11 March 2026 (press, contested counterweight)",
      "url": "https://www.investigativeeconomics.org/p/despite-massive-tunnel-project-anacostia",
      "publisher": {
       "name": null,
       "domain": "investigativeeconomics.org",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-c8b0ac763506ce39"
      ],
      "temporal": {
       "publishedAt": "2026-03-11",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-21",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Deliberately kept out of the snippet and impact, like the Comparitech and IQAir precedents, because it is a single outlet's reading of someone else's data. Llewellyn Jones, 'based on data from D.C.'s Department of Energy and Environment (DOEE)'s water quality reports to the EPA', reports the upper Anacostia out of compliance for E. coli about 92% of the time against under 40% before the tunnel, and attributes the gap to 'failing sewer pipes and illicit discharges' rather than CSOs. The underlying DOEE reports were not reached, and no DC Water response is included. The Anacostia Watershed Society's 2025 report card, by contrast, gave sample year 2024 a passing grade, its second highest since 2014.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     }
    ],
    "coverage": {
     "claimsTotal": 12,
     "claimsMapped": 12,
     "sourcesTotal": 12,
     "sourcesUsedByClaims": 12,
     "sourcesWithPublicationDate": 2,
     "sourcesWithArchive": 0,
     "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."
    ]
   }
  },
  {
   "id": "2026-08-21-source-dates",
   "createdAt": "2026-08-22T02:43:00Z",
   "effectiveAt": "2026-07-26",
   "changeType": "update",
   "summary": "Record the publication date of each source that states one; a source that publishes no date is marked null, and one that shows only a revision carries `updated` instead.",
   "preparedBy": {
    "type": "automation",
    "label": "AI-assisted evidence preparation",
    "humanApproved": false
   },
   "review": {
    "status": "unreviewed",
    "by": null,
    "date": null,
    "note": "Awaiting operator and domain-expert review; publication of this revision implies neither."
   },
   "changes": [
    {
     "operation": "replace",
     "path": "/snapshot/projectFingerprint",
     "summary": "Updated projectFingerprint to the current sourced project record."
    },
    {
     "operation": "replace",
     "path": "/snapshot/sources",
     "summary": "Updated sources to the current sourced project record."
    }
   ],
   "snapshotHash": "sha256:b5d1183023e90c042019c18cc80cae1a72670ea22a19879bb4a9a41bb1874d2a",
   "snapshot": {
    "asOf": "2026-07-26",
    "projectFingerprint": "sha256:ecc6a6f5462be385c77d571bee287333e31260828cc539dd8dc160dd776482a0",
    "assurance": {
     "status": "unreviewed",
     "scope": "evidence-passport-revision",
     "statement": "AI-assisted structural preparation. 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": "ongoing",
     "evidenceGrade": "official",
     "timeline": {
      "started": 2005,
      "ended": null
     }
    },
    "governance": {
     "operator": "DC Water (District of Columbia Water and Sewer Authority)",
     "actorTypes": [
      "utility"
     ],
     "fundingModel": "utility",
     "fundingDescription": "DC Water ratepayers through the Clean Rivers Impervious Area Charge — $24.23 per equivalent residential unit per month in FY2026, billed by measured impervious cover rather than water use",
     "cost": "≈$3.5bn, estimated at $2.6bn when the decree was signed in 2005",
     "ownership": null,
     "decisionRights": null,
     "exitConditions": null
    },
    "claims": [
     {
      "id": "clm-b23220304e86eb51",
      "field": "snippet",
      "text": "A 2005 federal consent decree with the EPA, the Justice Department and the District — not the utility's own choice — obliges DC Water to end combined sewer overflows",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-a2c555c8759fa950",
       "src-a5558be96eac7cd7"
      ],
      "supportNote": "The regulator's settlement page records a 2005 federal consent decree among EPA, the Department of Justice, the District of Columbia and DC Water, requiring storage tunnels in the Anacostia, Potomac and Rock Creek watersheds, with a $250,000 penalty plus $1.7m for rain gardens and low-impact development and $300,000 to the Chesapeake Bay Foundation. Independent press still describes the programme's 2030 completion date as 'the date set by a consent decree between the federal government, D.C. government and D.C. Water'.",
      "caveat": "The decree sets reduction targets rather than literal elimination: 98% of overflows eliminated in the Anacostia, 93% Potomac, 90% Rock Creek.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-baaab8a5b1098943",
      "field": "snippet",
      "text": "Three deep tunnels are in service",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-8d4c06a323f4cfab",
       "src-7da3e77dad5ac178",
       "src-8ca2e3ab4569ecee"
      ],
      "supportNote": "The programme page describes 'over 18 miles of tunnels' more than 100 feet below ground, draining to Blue Plains. The Anacostia River Tunnel entered service in March 2018; the Northeast Boundary Tunnel followed on 15 September 2023; the Piney Branch groundbreaking of 9 July 2026 is described as the programme's final major tunnel, with the Potomac Tunnel still being bored.",
      "caveat": "No single source states the count. Three is the entry's own tally of tunnels in service at the time of writing, from the individual project pages.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-22e9952a1237f49b",
      "field": "snippet",
      "text": "Twenty-two flow-metering stations and a calibrated sewer model produce the quarterly overflow accounting the decree demands",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-f89994afefe31af6",
       "src-124450ba0dbb1e87"
      ],
      "supportNote": "The collection-system page lists '22 flow-metering stations' across roughly 1,800 miles of sanitary and combined sewers. The combined-sewer page describes the accounting: 'DC Water uses a combination of flow meters and a computer model of the combined sewer system to measure and/or estimate the actual CSOs that have occurred on a quarterly basis', published as quarterly operation reports and consent-decree quarterly reports.",
      "caveat": "The operator says 'computer model'. That it is calibrated is the entry's characterisation, not the operator's word.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-a4ad12ae2461c056",
      "field": "snippet",
      "text": "while inflatable dams, dynamically controlled weirs and outfall gates steer the flow",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-f89994afefe31af6"
      ],
      "supportNote": "The operator states that the system is regulated by 'inflatable dams, dynamically controlled weirs, outfall gates and other flow regulating devices', alongside nine wastewater pumping stations and some 75,000 catch basins and manholes. This actuation layer is why the entry treats the tunnels as more than civil engineering.",
      "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-fc8bf4881ef9df05",
      "field": "snippet",
      "text": "Every District property pays by impervious area",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-218e78bd0aa21fa4",
       "src-7252e6f2161d35bd"
      ],
      "supportNote": "The charge is levied on impervious area rather than on water consumed, at $24.23 per equivalent residential unit per month from 1 October 2025, across six tiers from 0.6 ERU at $14.54 to 13.5 ERU at $327.11. An ERU is 'a statistical median of the amount of impervious surface area in a single-family residential property, measured in square feet'.",
      "caveat": "Measuring by satellite has a political cost the press records: a councilmember objected that 'a picture from a satellite doesn't capture that very well, which puts the onus back on the homeowner', and churches and nonprofits called the charge a heavy burden, prompting council relief programmes.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-a3b82e9cb3687273",
      "field": "impact",
      "text": "DC Water reports the Anacostia River Tunnel kept about 4.5 billion gallons of sewage out of the river in 2018 alone, its first year",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-18cc5d172d1d6dd1"
      ],
      "supportNote": "The figure is carried in the operator's release title and matched by independent WJLA coverage under the same number.",
      "caveat": "A finer figure — 4.57 billion gallons and nearly 900 tons of trash and solids for March to 31 December 2018 — appeared in search results but was not read on a rendered page, so the entry rounds rather than quoting it.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-9efab099491aa0fa",
      "field": "impact",
      "text": "that overflows to the Anacostia are down roughly 90% since it opened in March 2018",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-7da3e77dad5ac178"
      ],
      "supportNote": "The project page states that 'combined sewer overflows to the Anacostia River have been reduced by 90 percent' since completion in March 2018. The tunnel is about 12,500 feet long, 23 feet in diameter, 80 to 120 feet deep.",
      "caveat": "This is the utility's own reporting of its own reduction, computed from the quarterly meter-plus-model accounting rather than an independent measurement.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-df494bf167c99772",
      "field": "impact",
      "text": "DC Water expects 98% for the Anacostia and 96% system-wide, and puts the chance of flooding in Northeast in an average rainfall year at 7%, down from 50%",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-8d4c06a323f4cfab",
       "src-a2c555c8759fa950"
      ],
      "supportNote": "The programme page states targets of 96% system-wide overflow reduction, 98% Anacostia, 93% Potomac and 90% Rock Creek, and chronic flooding risk in Northeast cut 'from 50% to 7%'. The same reduction percentages appear as the decree's expected outcomes on the regulator's settlement page.",
      "caveat": "These are targets, not measurements, and the entry treats them as such.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-72340765c972c797",
      "field": "impact",
      "text": "All figures are the utility's own; the decree's compliance accounting is quarterly, from flow meters plus a model, not a live public measurement",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-124450ba0dbb1e87"
      ],
      "supportNote": "The only real-time public signal the operator describes is a warning light: 'DC Water has installed a series of CSO Event Indicator Lights to notify river users of CSO events' — red during an active overflow, yellow for 24 hours afterwards. Everything else is quarterly, from meters and a model.",
      "caveat": "No predictive or real-time control of the tunnel system is described anywhere on the operator's site, and the entry claims none.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-1b953d87e7837116",
      "field": "lesson",
      "text": "The 2015-16 modification let green infrastructure try to replace concrete in Rock Creek and shrink the Potomac tunnel",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-fa917666e2605d06"
      ],
      "supportNote": "The modification proposed 'Using green infrastructure to retain the first 1.2 inches of rainwater on 365 acres in the Rock Creek area and 133 acres in the Potomac watershed', potentially 'eliminating the Rock Creek storage tunnel and significantly decreasing the size of the Potomac tunnel', in exchange for five more years in those two watersheds. The Anacostia stayed on schedule.",
      "caveat": "The regulator announced the proposal in May 2015; the operator dates the signed modification to 14 January 2016, which is why the entry gives a span rather than a single year.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-21486f455bb5688b",
      "field": "lesson",
      "text": "DC Water assessed it, then broke ground on the Piney Branch Tunnel in July 2026 as the programme's final major tunnel",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-8ca2e3ab4569ecee"
      ],
      "supportNote": "Groundbreaking was on 9 July 2026 for 'about a half-mile, 22-foot wide tunnel deep underground' holding 'at least 4.2 million gallons', due 'by the end of 2029', cutting Piney Branch overflow volume by 96% and frequency from about 25 times a year to about once. The 2015-16 modification had contemplated green infrastructure replacing a 9.5-million-gallon Rock Creek storage facility; the tunnel is being built.",
      "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-c8b0ac763506ce39",
      "field": "lesson",
      "text": "the tunnels intercept combined sewage, not failing pipes or illicit connections",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-8c5df9904b922cd8"
      ],
      "supportNote": "A single outlet, reading the District's own water quality reports to the EPA, puts the upper Anacostia out of compliance for E. coli about 92% of the time against under 40% before the tunnel, and attributes the gap to failing sewer pipes and illicit discharges rather than to combined sewer overflows.",
      "caveat": "Deliberately kept out of the snippet and impact. The underlying environment-department reports were not reached, no operator response is included, and the Anacostia Watershed Society's 2025 report card gave sample year 2024 a passing grade, its second highest since 2014. The claim carried here is the structural one — what the tunnels are built to catch — not the outlet's compliance figure.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     }
    ],
    "sources": [
     {
      "id": "src-a2c555c8759fa950",
      "title": "US EPA — District of Columbia Water and Sewer Authority Clean Water settlement (regulator)",
      "url": "https://www.epa.gov/enforcement/district-columbia-water-and-sewer-authority-district-columbia-clean-water-settlement",
      "publisher": {
       "name": null,
       "domain": "epa.gov",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-b23220304e86eb51",
       "clm-df494bf167c99772"
      ],
      "temporal": {
       "publishedAt": "2015-05-18",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The decree itself, sentence-level: a 2005 federal consent decree among EPA, the Department of Justice, the District of Columbia and DC Water, requiring storage tunnels in the Anacostia, Potomac and Rock Creek watersheds. Penalty $250,000, plus $1.7m for rain gardens and low-impact development and $300,000 to the Chesapeake Bay Foundation for green roofs. Anacostia work due 2025, Potomac and Rock Creek extended to 2030. Expected outcomes stated as 98% of CSOs eliminated in the Anacostia, 93% Potomac, 90% Rock Creek.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-fa917666e2605d06",
      "title": "US Department of Justice — strategy to reduce the District's sewer overflows will include green infrastructure, 20 May 2015 (regulator)",
      "url": "https://www.justice.gov/archives/opa/pr/strategy-reduce-district-columbia-s-sewer-overflows-will-include-green-infrastructure",
      "publisher": {
       "name": null,
       "domain": "justice.gov",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-1b953d87e7837116"
      ],
      "temporal": {
       "publishedAt": "2015-05-20",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The modification, sentence-level: 'Using green infrastructure to retain the first 1.2 inches of rainwater on 365 acres in the Rock Creek area and 133 acres in the Potomac watershed', potentially 'eliminating the Rock Creek storage tunnel and significantly decreasing the size of the Potomac tunnel', in exchange for 'an additional five years to complete implementation in the Potomac and Rock Creek watersheds'. The Anacostia system stayed on schedule: 'Major portions of this tunnel system are scheduled for completed and in operation in 2018.' DOJ announced the proposal in May 2015; DC Water dates the signed modification to 14 January 2016.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-f89994afefe31af6",
      "title": "DC Water — Wastewater Collection (operator; the actuation and metering layer)",
      "url": "https://www.dcwater.com/about-dc-water/what-we-do/wastewater-collection",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-22e9952a1237f49b",
       "clm-a4ad12ae2461c056"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The reason this is an atlas entry and not only civil engineering, sentence-level: the system includes '22 flow-metering stations' and is regulated by 'inflatable dams, dynamically controlled weirs, outfall gates and other flow regulating devices', alongside '9 wastewater pumping stations', 'approximately 1,800 miles of sanitary and combined sewers' and '75,000 catch basins and manholes'.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-124450ba0dbb1e87",
      "title": "DC Water — Combined Sewer System (operator; the measurement and notification layer)",
      "url": "https://www.dcwater.com/about-dc-water/what-we-do/wastewater-collection/css",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-22e9952a1237f49b",
       "clm-72340765c972c797"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "How overflows are counted, sentence-level: 'DC Water uses a combination of flow meters and a computer model of the combined sewer system to measure and/or estimate the actual CSOs that have occurred on a quarterly basis', published as CSO Division Quarterly Operation Reports and Long Term Control Plan Consent Decree Quarterly Reports. The only real-time public signal: 'DC Water has installed a series of CSO Event Indicator Lights to notify river users of CSO events' — red for an active overflow, yellow for 24 hours afterwards. No predictive or real-time control of the tunnel system is described anywhere on DC Water's site, and the entry claims none.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-8d4c06a323f4cfab",
      "title": "DC Water — Clean Rivers Project (operator)",
      "url": "https://www.dcwater.com/cleanrivers",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-baaab8a5b1098943",
       "clm-df494bf167c99772"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Programme scope and targets, sentence-level: 'over 18 miles of tunnels' more than 100 feet below ground, fed by diversion chambers, approach channels, roughly 100-foot drop shafts and adits, all draining to Blue Plains. Targets stated as 96% system-wide CSO reduction, 98% Anacostia, 93% Potomac, 90% Rock Creek, and chronic flooding risk in Northeast cut 'from 50% to 7%'. The page lists a 2016 amended consent decree and a 2020 joint stipulation of non-material modification. These are targets, not measurements — the entry treats them as such.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-7da3e77dad5ac178",
      "title": "DC Water — Anacostia River Tunnel Project (operator)",
      "url": "https://www.dcwater.com/projects/anacostia-river-tunnel-project",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-baaab8a5b1098943",
       "clm-9efab099491aa0fa"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The 90% figure and its owner, sentence-level: 'combined sewer overflows to the Anacostia River have been reduced by 90 percent' since completion in March 2018. Tunnel is 'approximately 12,500 feet', '23-foot diameter', 'approximately 80 to 120 feet deep'. The page mentions diversion facilities and 'ventilation control facilities to regulate air flow' but no gates, pumping or monitoring detail — so the control layer is sourced from the collection-system pages instead.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-18cc5d172d1d6dd1",
      "title": "DC Water — Anacostia River Tunnel saves river from 4.5 billion gallons of sewage overflow in 2018 (operator)",
      "url": "https://www.dcwater.com/about-dc-water/media/news/dc-waters-anacostia-river-tunnel-saves-river-45-billion-gallons-sewage",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-a3b82e9cb3687273"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "First-year volume, carried in the release title and matched by independent WJLA coverage under the same figure. Search results also gave 4.57 billion gallons and nearly 900 tons of trash and solids for March to 31 December 2018, but that sentence was not read on a rendered page, so the entry rounds to 'about 4.5 billion gallons' rather than quoting the finer number.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-8ca2e3ab4569ecee",
      "title": "DC Water — breaks ground on Piney Branch Tunnel, final phase of the Clean Rivers Project (operator)",
      "url": "https://www.dcwater.com/about-dc-water/media/news/dc-water-breaks-ground-piney-branch-tunnel-final-phase-dc-clean-rivers",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-baaab8a5b1098943",
       "clm-21486f455bb5688b"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The lesson's evidence, sentence-level: groundbreaking 9 July 2026 on 'about a half-mile, 22-foot wide tunnel deep underground' holding 'at least 4.2 million gallons', finished 'by the end of 2029', cutting Piney Branch overflow volume by 96% and frequency from about 25 times a year to about once. The 2015-16 modification had contemplated green infrastructure replacing a 9.5-million-gallon Rock Creek storage facility; the tunnel is being built.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-218e78bd0aa21fa4",
      "title": "DC Water — Clean Rivers Impervious Area Charge rates (operator)",
      "url": "https://www.dcwater.com/customer-center/rates-and-fees/impervious-area-charge",
      "publisher": {
       "name": null,
       "domain": "dcwater.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-fc8bf4881ef9df05"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The financing mechanism, exactly: $24.23 per equivalent residential unit per month effective 1 October 2025 (FY2026). An ERU is 'a statistical median of the amount of impervious surface area in a single-family residential property, measured in square feet'. Six tiers, from 0.6 ERU at $14.54 a month for 100-699 sq ft of impervious cover to 13.5 ERU at $327.11 for 11,100 sq ft and above. The charge is levied on impervious area, not on water consumed.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-7252e6f2161d35bd",
      "title": "51st News — your DC Water bill could get more expensive, January 2026 (press)",
      "url": "https://51st.news/your-dc-water-bill-could-get-more-expensive/",
      "publisher": {
       "name": null,
       "domain": "51st.news",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-fc8bf4881ef9df05"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Cost and the political counterweight: 'a multi-year $3.5 billion infrastructure project kicked off in 2009', construction wrapping up in 2030, 'each ERU now costs homeowners around $24 a month', projected to 'top out at more than $32 per ERU per month' by 2030. Ward 6 Councilmember Charles Allen on the satellite-measured billing: 'a picture from a satellite doesn't capture that very well, which puts the onus back on the homeowner.' Churches and nonprofits called the charge 'a heavy burden', prompting council relief programmes.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-a5558be96eac7cd7",
      "title": "WTOP — DC Water takes big step forward in Potomac River Tunnel project, January 2026 (press)",
      "url": "https://wtop.com/dc/2026/01/dc-water-takes-big-step-forward-in-potomac-river-tunnel-project/",
      "publisher": {
       "name": null,
       "domain": "wtop.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-b23220304e86eb51"
      ],
      "temporal": {
       "publishedAt": "2026-01-13",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Current construction status: the cutterhead for TBM Mary lowered down a 100-foot shaft at West Potomac Park, tunnelling to start spring 2026 on the 5.5-mile run from the Georgetown waterfront to Blue Plains, with a second machine, Emily, for the 3.1-mile southern segment. Substantial completion expected 2028, full completion February 2030, 'the date set by a consent decree between the federal government, D.C. government and D.C. Water'. Read via search summary rather than a rendered page; the 2030 decree deadline is independently confirmed by the EPA settlement page.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-8c5df9904b922cd8",
      "title": "Investigative Economics — despite massive tunnel project, Anacostia still filled with fecal matter, 11 March 2026 (press, contested counterweight)",
      "url": "https://www.investigativeeconomics.org/p/despite-massive-tunnel-project-anacostia",
      "publisher": {
       "name": null,
       "domain": "investigativeeconomics.org",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-c8b0ac763506ce39"
      ],
      "temporal": {
       "publishedAt": "2026-03-11",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Deliberately kept out of the snippet and impact, like the Comparitech and IQAir precedents, because it is a single outlet's reading of someone else's data. Llewellyn Jones, 'based on data from D.C.'s Department of Energy and Environment (DOEE)'s water quality reports to the EPA', reports the upper Anacostia out of compliance for E. coli about 92% of the time against under 40% before the tunnel, and attributes the gap to 'failing sewer pipes and illicit discharges' rather than CSOs. The underlying DOEE reports were not reached, and no DC Water response is included. The Anacostia Watershed Society's 2025 report card, by contrast, gave sample year 2024 a passing grade, its second highest since 2014.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     }
    ],
    "coverage": {
     "claimsTotal": 12,
     "claimsMapped": 12,
     "sourcesTotal": 12,
     "sourcesUsedByClaims": 12,
     "sourcesWithPublicationDate": 4,
     "sourcesWithArchive": 0,
     "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."
    ]
   }
  }
 ]
}