Build rock check dams on an invited Nogales hillside to slow the monsoon

The bare, gullied hillsides above Nogales shed monsoon rain in minutes, feeding the flash floods below and losing their own soil with every storm. One-rock-high check dams — loose rock laid across small gullies on invited land — slow the water, catch sediment, and green the slope, a technique proven across the borderlands by decades of restoration work. Standard: Borderlands one-rock dam / erosion control practice (Zeedyk method); SDG 15 Life on Land. Proof: Photo per dam + sequence map with GPS Method (Borderlands one-rock dam / erosion control practice (Zeedyk method); SDG 15 Life on Land.): 1. Walk the invited slope with the host and mark small active gullies suitable for one-rock dams. 2. Gather loose local rock and lay each dam one rock high, keyed into the gully sides, spillway in the middle. 3. Build several dams in sequence down each gully. 4. Check each dam is stable underfoot pressure and no rock is higher than one course. 5. Photograph each dam and map the sequence with date and GPS. Done when: Photo per dam + sequence map with GPS

Where

Invited hillside parcels off N Royal Rd area, Nogales, AZ 85621

Pay

$95 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 per dam + sequence map with GPS

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

Level

intermediate

Open until

2026-09-01

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 dry-weather / AMD field screening

Bring

• GPS phone
• pH meter or strips
• conductivity meter
• ammonia + iron test kit as specified
• surfactant screen if specified
• gloves
• camera

Steps

1. 1. Navigate to the outfall/reach; record GPS; photograph it, capturing any visible flow or staining.
2. 2. Note whether flow is present in dry weather (yes/no).
3. 3. Measure and record pH, conductivity, and each specified analyte per kit instructions.
4. 4. Log any color, odor, floc, or aquatic-life observation.
5. 5. Enter all readings with units, GPS, time, and photos into the proof record; sign.

If it does not match the plan

• Dry-weather flow present with elevated conductivity/ammonia/surfactants -> flag suspected illicit discharge for the responsible agency.
• pH < 6 with visible iron floc -> tag suspected acid mine drainage; recommend metals lab panel.

What counts as done

• pH + conductivity recorded with units
• Each specified analyte recorded with a value
• Dry-weather flow present? recorded yes/no
• GPS waypoint + timestamped photo

Proof is measured against these, not judged by taste.