{
  "city": "Detroit",
  "state": "MI",
  "slug": "detroit",
  "hardness_facts": [
    {
      "utility": "Detroit Water and Sewerage Department",
      "measure": "Total hardness",
      "value_as_published": "Average 107 ppm, range 96-142 ppm",
      "period": "Calendar year 2025",
      "source_title": "Detroit Water Quality Report, 2025 Results (DWSD - WQR - 2025 - Final)",
      "source_url": "https://detroitmi.gov/sites/detroitmi.localhost/files/2026-06/DWSD%20-%20WQR%20-%202025%20-%20Final%20-1.pdf"
    }
  ],
  "published_span_mg_per_l": [
    96,
    142
  ],
  "span_converted_from_grains": false,
  "usgs_class": "moderately hard to hard",
  "usgs_class_source": "https://www.usgs.gov/water-science-school/science/hardness-water",
  "notes": [],
  "local_details": {
    "disinfectant": {
      "text": "The Detroit report lists a chlorine residual added to control microbes, ranging 0.59 to 1.08 ppm in 2025. It does not mention chloramine.",
      "kind": "chlorine",
      "source_title": "DWSD 2025 Water Quality Report",
      "source_url": "https://detroitmi.gov/sites/detroitmi.localhost/files/2026-06/DWSD%20-%20WQR%20-%202025%20-%20Final%20-1.pdf",
      "evidence_ids": [
        "DETROI-L-01"
      ]
    },
    "source_water": {
      "text": "Detroit homes get Detroit River water treated at four Great Lakes Water Authority plants.",
      "source_title": "DWSD 2025 Water Quality Report",
      "source_url": "https://detroitmi.gov/sites/detroitmi.localhost/files/2026-06/DWSD%20-%20WQR%20-%202025%20-%20Final%20-1.pdf",
      "evidence_ids": [
        "DETROI-L-02"
      ]
    },
    "service": {
      "text": "The Great Lakes Water Authority treats the water and moves it to the city, and the Detroit Water and Sewerage Department delivers it to neighborhoods.",
      "source_title": "DWSD 2025 Water Quality Report",
      "source_url": "https://detroitmi.gov/sites/detroitmi.localhost/files/2026-06/DWSD%20-%20WQR%20-%202025%20-%20Final%20-1.pdf",
      "evidence_ids": [
        "DETROI-L-03"
      ]
    }
  },
  "sources_checked_on": "2026-10-27",
  "site": "https://detroitwatersystems.com/",
  "brand": "Detroit Water Systems by My Home Water System",
  "taking_requests": false
}