Snowmelt and storm water
Reno-area homes with basements and crawlspaces see most water problems during snowmelt and heavy rain, when water collects against foundations faster than it can drain. Keep gutters clean, extend downspouts well away from the foundation, grade soil away from the house, and keep window wells clear and covered. Crawlspaces should have a vapor barrier over the soil and drainage if water collects.
The river and low ground
The Truckee River runs through Reno, and NOAA's California Nevada River Forecast Center tracks it at a gauge in the city. Homes on low ground near the river or creeks may have higher groundwater and more flood risk. Sump pumps with battery backup and high-water alarms are worth considering in those areas.
Freezing discharge lines
Washoe County's residential design criteria set a 24-inch frost line depth and a 17°F winter design temperature, and NOAA's engineering weather data for the Reno airport records about 123 freeze-thaw cycles a year. Sump pump discharge lines that run across the yard can freeze in winter, causing the pump to run against a blocked line or water to back up. Slope discharge lines so they drain completely, bury them below the frost or insulate them where possible, and install a freeze-resistant outlet near the house that lets water escape if the line freezes.
Frost and foundation walls
Water that saturates soil against basement walls and freezes adds pressure and can widen cracks. Good drainage reduces that risk. Leaking cracks can be sealed with injection; bowing walls need structural evaluation.
Radon
The EPA recommends testing all homes for radon, a naturally occurring radioactive gas that can enter through foundations. Testing is especially worthwhile before finishing a basement. Mitigation systems can reduce high levels.
Finishing a basement
Fix moisture first, test for radon, plan egress windows for bedrooms, and use rigid foam insulation against concrete walls.
Before you hire
Ask Reno contractors where the water is coming from, how they'll keep discharge lines from freezing, what backup they recommend, and whether permits are needed. Look up the contractor with the Nevada State Contractors Board.
Crawlspaces
Many Reno-area homes have crawlspaces. A heavy vapor barrier over the soil, sealed at seams and walls, good drainage, and the right venting or conditioning for the design keep them dry. Check after snowmelt for standing water and wet insulation.
Window wells
Window wells collect snow and water. Keep them clear, covered and drained so they don't fill during melt.
Dehumidifiers
Even in a dry climate, basements can be humid in summer when warm air meets cool walls. A dehumidifier with a drain line helps.
Outside first
Gutters, downspouts, grading and window well covers solve many Reno basement and crawlspace water problems before any waterproofing is needed.
Sealed pit lids
A sealed lid on the sump pit keeps humid air and soil gases out of the basement and keeps debris out of the pump.