Mission Hills contains some of the oldest residential plumbing in San Diego, and with it, some of the highest potential for pipe-contributed contamination. Homes from the 1910s may still have original lead service lines connecting to the city main — lead pipes that have been in continuous contact with drinking water for over a century. Galvanized steel supply pipes installed 80–100 years ago are severely corroded and shedding rust, iron, and sediment. Pre-1986 copper joints with lead-based solder continue to leach lead into standing water, particularly in first-draw samples.Homewerx performs comprehensive dual-point testing for Mission Hills homes with particular attention to lead and copper levels in first-draw samples — water that has sat in contact with pipe walls overnight, where metal leaching is highest. We compare tap results to main samples to quantify exactly what the home's plumbing is adding. For homes with confirmed lead service lines or elevated first-draw lead, we provide immediate guidance on protective measures while longer-term solutions (repiping, filtration) are planned.