{
  "city": "Oklahoma City",
  "state": "OK",
  "slug": "oklahoma-city",
  "hardness_facts": [],
  "published_span_mg_per_l": null,
  "span_converted_from_grains": false,
  "usgs_class": null,
  "usgs_class_source": "https://www.usgs.gov/water-science-school/science/hardness-water",
  "notes": [
    "OKC's water quality reports for 2016, 2017 and 2019 through 2025 list no hardness figure.",
    "A 2017 city plan describes Hefner water as generally hard and Draper water as much softer, and a 2024 city project document describes raw Lake Hefner water as high in hardness. Neither gives a number."
  ],
  "local_details": {
    "disinfectant": {
      "text": "OKC disinfects with a small amount of chlorine and ammonia, which forms chloramine, measured at 3.57 ppm at Hefner and 3.25 ppm at Draper in 2025.",
      "kind": "chloramine",
      "source_title": "OKC Utilities Consumer Confidence Report for 2025",
      "source_url": "https://www.okc.gov/files/assets/city/v/1/utilities/documents/water-quality-reports/ccr-june-2026-for-2025-reporting_063026cb-publishedv2071426.pdf",
      "evidence_ids": [
        "OKLAHO-L-01"
      ]
    },
    "source_water": {
      "text": "OKC draws on five reservoirs. Canton water flows down the North Canadian River to Lake Hefner, and Atoka and McGee Creek water travels by pipeline to Lake Stanley Draper, for treatment at the Hefner and Draper plants.",
      "source_title": "OKC Utilities Consumer Confidence Report for 2025",
      "source_url": "https://www.okc.gov/files/assets/city/v/1/utilities/documents/water-quality-reports/ccr-june-2026-for-2025-reporting_063026cb-publishedv2071426.pdf",
      "evidence_ids": [
        "OKLAHO-L-02"
      ]
    },
    "softening": {
      "text": "Partly. A 2024 city project document describes the Hefner plant as a lime softening plant. It does not describe the Draper plant.",
      "source_title": "OKC Hefner Water Treatment Plant Clarifier Rehabilitation (2024)",
      "source_url": "https://okc.gov/home/showpublisheddocument/42328/638525013580870000",
      "evidence_ids": [
        "OKLAHO-L-03"
      ]
    },
    "service": {
      "text": "OKC Utilities serves the city from its Hefner and Draper plants, except The Falls neighborhood, which gets City of Edmond water under an agreement.",
      "source_title": "OKC Utilities Consumer Confidence Report for 2025",
      "source_url": "https://www.okc.gov/files/assets/city/v/1/utilities/documents/water-quality-reports/ccr-june-2026-for-2025-reporting_063026cb-publishedv2071426.pdf",
      "evidence_ids": [
        "OKLAHO-L-04"
      ]
    }
  },
  "sources_checked_on": "2026-10-27",
  "site": "https://okcwatersystems.com/",
  "brand": "OKC Water Systems by My Home Water System",
  "taking_requests": false
}