legends · 4 min read ·
Water Quality Report
A water company's annual report is followed by a laboratory addendum: the water carries the DNA of the person who draws it.
**Brackwater Utilities — Annual Drinking Water Quality Report (Zone 4, Fenwick & Marlow)**
*Tests were carried out at 112 customer taps. Results are compared with the regulatory limits.*
- **Parameter · Limit · Result (mean) · Result (max)**
- Turbidity · 4 NTU · 0.3 · 0.9
- Chlorine (free) · 0.5 mg/l · 0.2 · 0.4
- Lead · 10 µg/l · 1.1 · 3.0
- Coliforms · 0 /100 ml · 0 · 0
- E. coli · 0 /100 ml · 0 · 0
- Conductivity · 2,500 µS/cm · 540 · 610
*Conclusion: water supplied to Zone 4 meets all regulatory standards.*
· · ·
**Laboratory addendum (Estuary Analytical, 3 October)**
Samples from Zone 4, collected 29 September. Standard parameters: compliant.
**Supplementary analysis (metagenomic screen, requested following customer reports of unusual taste).** DNA was extracted from 5 litres of water from each of 12 taps and sequenced. The majority of reads match common freshwater bacteria. A minority (0.4–2.1%) match *Homo sapiens*.
Human DNA in treated mains water is unusual but not unknown; it may originate from skin cells or the human operators. The proportion here is high.
More significantly, the human DNA is not diverse. Sequencing identifies not a mixture of individuals, as would be expected from the population of a zone, but a single individual in each sample. Twelve samples, twelve individuals. In every case, the donor is the customer who drew the sample from their own tap.
· · ·
**Customer report log (Brackwater Utilities, 4–12 October)**
*#118: "The water tastes like me. I don't know how else to say it. It tastes like my own mouth."*
*#124: "I filled a glass and let it settle and there was a hair floating in it, which I recognise, because it was grey and had a kink."*
*#131: "My husband says it tastes like his sweat after a long walk. He won't drink it. I do. It's rather nice."*
· · ·
**Technical memo (Brackwater Utilities, 14 October)**
To: Operations
Re: Zone 4 customer complaints
1. The supply is compliant. Regulatory sampling has found no failure.
2. The laboratory reports that tap water in Zone 4 contains human DNA matching the occupants of the properties tested.
3. This is not physically possible if the water has not been in contact with the occupants.
4. Water in the mains is replaced every 36 hours. No person's DNA can have entered the mains upstream of the customer's tap.
5. Therefore the DNA is entering at the tap.
We have asked for an independent audit.
· · ·
**Independent audit (Hartley Water Consultants, 20 October)**
We drew samples at the treatment works, at the service reservoir, at two hydrants, at the stop tap of an empty house, and at the taps of 30 occupied houses.
Samples from the treatment works, the reservoir and the hydrants: no human DNA. Sample from the empty house: none. Samples from the occupied houses: human DNA, in each case that of the household.
The water changes when it enters a house. Within a few seconds of the tap being opened, the water that flows is no longer the water that was in the pipe. At the point of the inside stop tap, the sample is clean. At the kitchen tap, 4 m further on, it contains the person's DNA.
· · ·
**Boil water notice (Brackwater Utilities, 24 October)**
*Residents of Zone 4 are advised to boil all water used for drinking and cooking. Bring to a rolling boil for at least one minute and allow to cool. This is a precautionary measure. The water is safe for washing and bathing.*
*Residents are asked not to run taps unnecessarily. Residents who feel uneasy after drinking are advised to rest.*
· · ·
**Boil water notice — follow-up (Brackwater Utilities, 31 October)**
*Boil notice for Zone 4 is extended until further notice.*
*We have received a number of reports that boiling the water produces a faint sound. We confirm that the water, when boiled, makes a sound. The sound is not harmful. It is the sound of the water coming to the boil. Some residents describe it as a murmur. Some describe it as a conversation. It is the same conversation in every kitchen in Zone 4. It sounds like the residents talking quietly to each other in the next room.*
*Residents are advised not to listen for the words.*