Swap the filter cartridge on a household water system every month (2026-07-19)

Households in Iztapalapa that already run a basic water filter often keep using it long after the cartridge is spent, because a clogged filter still looks fine from the outside. A missed swap quietly lets sediment and microbes from trucked or tank-stored water back into drinking water. A simple monthly cartridge check and swap keeps the filter actually doing its job. Standard: WHO household water treatment guidance; SDG 6 (Clean Water and Sanitation) Proof: Photo of the new cartridge installed plus swap date Method (WHO household water treatment guidance; SDG 6 (Clean Water and Sanitation)): 1. Confirm the host invites the visit and locate the household filter unit. 2. Check the cartridge age or condition against the manufacturer's replacement window. 3. Remove the spent cartridge and install a new one, following the unit's seal instructions. 4. Run water through the new cartridge for the recommended flush time before use. 5. Photograph the new cartridge in place and record the swap date for the next visit. Done when: Photo of the new cartridge installed plus swap date

Where

Invited home kitchen, Barrio San Lucas, Iztapalapa, CDMX 09090

Pay

$140 proposed

This packet is not funded yet, so this figure is a proposed price and not money waiting in escrow. If a buyer funds it, approved proof settles that price onchain. If nobody funds it, approved proof earns provable credit toward the work instead of cash. You see which before you claim, never after.

Proof

Photo of the new cartridge installed plus swap date

This is exactly what gets it approved. Nothing settles without it.

Level

entry

Open until

2026-08-19

How this work is done

A documented method, so this packet comes out the same whoever does it. Typically 30–60 minutes. Method of record: EPA drinking-water sampling (3Ts / LCR first-draw where lead is in scope)

Bring

• GPS-capable phone
• test kit for each named analyte (nitrate/coliform/arsenic/lead as specified)
• clean sample bottle + label
• nitrile gloves
• camera

Steps

1. 1. Navigate to the sampling point; confirm GPS is inside the posting radius; record the waypoint.
2. 2. Photograph the tap or wellhead with a legible timestamp.
3. 3. If first-draw is required, sample after >=6h stagnation; if flushed, run the tap 2-3 minutes first, then sample.
4. 4. Fill the bottle without touching the inside; cap immediately.
5. 5. Run each test per kit instructions; wait the exact develop/incubation time; read and record every value with units.
6. 6. Record coliform as present/absent after the stated incubation window.
7. 7. Enter all readings, units, GPS, time, and photos into the proof record; sign it.

If it does not match the plan

• Nitrate > 10 mg/L -> tag 'exceeds EPA MCL'; advise no infant consumption pending certified-lab confirmation.
• Total coliform present -> advise disinfection + retest; recommend lab confirmation.
• Arsenic > 10 ppb or Lead > 15 ppb -> tag exceedance; recommend certified-lab confirmation before any consumption guidance.

What counts as done

• GPS waypoint recorded inside the posting radius
• Timestamped photo of the exact sampling point
• Each required analyte recorded with a numeric value + units (or present/absent)
• Sampling type (first-draw vs flushed) explicitly noted

Proof is measured against these, not judged by taste.