{
  "city": "Houston",
  "state": "TX",
  "slug": "houston",
  "hardness_facts": [
    {
      "utility": "Houston Public Works",
      "measure": "Total hardness, main system",
      "value_as_published": "Average 135.5 ppm, range 43.5-229 ppm",
      "period": "Calendar year 2025",
      "source_title": "Houston Water Quality Report | Jan - Dec 2025",
      "source_url": "https://www.houstonpublicworks.org/sites/g/files/nwywnm456/files/doc/003_2025_houston_water_quality_report.pdf"
    }
  ],
  "published_span_mg_per_l": [
    43.5,
    229
  ],
  "span_converted_from_grains": false,
  "usgs_class": "soft to very hard",
  "usgs_class_source": "https://www.usgs.gov/water-science-school/science/hardness-water",
  "notes": [
    "Houston reports both chlorine and chloramine as disinfectants, without saying which system uses which.",
    "Several smaller Houston systems, such as Kingwood, report their own hardness in the same 2025 report."
  ],
  "local_details": {
    "disinfectant": {
      "text": "The main Houston system uses chloramine. Some smaller city systems served only by wells, such as Kingwood, use chlorine.",
      "kind": "varies",
      "source_title": "Houston 2025 Water Quality Report",
      "source_url": "https://www.houstonpublicworks.org/sites/g/files/nwywnm456/files/doc/003_2025_houston_water_quality_report.pdf",
      "evidence_ids": [
        "HOUSTO-L-01"
      ]
    },
    "source_water": {
      "text": "The main system draws mostly surface water from the Trinity River (Lake Livingston) and San Jacinto River (Lake Conroe and Lake Houston), plus deep wells in the Evangeline and Chicot aquifers.",
      "source_title": "Houston 2025 Water Quality Report",
      "source_url": "https://www.houstonpublicworks.org/sites/g/files/nwywnm456/files/doc/003_2025_houston_water_quality_report.pdf",
      "evidence_ids": [
        "HOUSTO-L-02"
      ]
    },
    "service": {
      "text": "Houston Public Works runs six separate water systems: the main system, Kingwood, Willow Chase, District 73, District 82 and Belleau Woods, which buys water from Humble. Each has its own results in the report.",
      "source_title": "Houston 2025 Water Quality Report",
      "source_url": "https://www.houstonpublicworks.org/sites/g/files/nwywnm456/files/doc/003_2025_houston_water_quality_report.pdf",
      "evidence_ids": [
        "HOUSTO-L-03"
      ]
    }
  },
  "sources_checked_on": "2026-10-27",
  "site": "https://houstonhomewatersystems.com/",
  "brand": "Houston Home Water Systems by My Home Water System",
  "taking_requests": true
}