Based on current monitoring, Timber Lake holds an above-average drinking water safety record for SD — violations are infrequent and typically minor when they do appear.

Data: EPA SDWIS Last verified: 2026-06-03

Overview

We track water quality and home safety data for 1 ZIP code in Timber Lake, South Dakota (population ~911), covering 2 community water systems serving approximately 2,689 people region-wide.

No EPA violations recorded across any ZIP codes in Timber Lake — an excellent indicator of water quality.

Home Safety Score

Average Home Safety Score for Timber Lake: B (83/100)

The score combines three factors:

Factor	What It Measures
Water Quality	EPA violations and compliance history
Lead Levels	90th percentile lead concentration vs EPA action level
Radon Risk	EPA radon zone classification

Water Sources

Timber Lake water systems draw from: Groundwater.

Lead & Copper

• Average lead level (90th percentile): 0.0050 mg/L (EPA action level: 0.015 mg/L)
• 0 ZIP codes exceed the EPA lead action level

Radon Risk

Dominant radon zone: Zone 2 (Moderate Risk)

The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.

Areas with No Violations

All ZIP Codes in Timber Lake

• 57656 [B]

Data Sources

• Water quality: EPA Safe Drinking Water Information System (SDWIS)
• Lead/copper: EPA Lead and Copper Rule sampling data
• Radon: EPA Map of Radon Zones

Updated daily.

Housing Age Profile

The character of Timber Lake's housing stock is one of deep historical layering — a median build year of 1979 signals a city built largely before the plumbing era changes of 1986 and 1970. Lead-soldered copper joints and, in the oldest properties, lead service lines are commonly present in this inventory. That context shapes what individual water testing may reveal, particularly in neighborhoods where the oldest housing is concentrated.

1979

Median Year Built

77%

Pre-1986 (Lead Paint Risk)

39%

Pre-1970 (Lead Pipes Risk)

Pre-1970 (39%) 1970–1986 (38%) Post-1986 (23%)

Over half of homes in Timber Lake were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.

Source: U.S. Census Bureau ACS B25034.

Cost Context: What Remediation Means for Timber Lake Homeowners

Across Timber Lake, the equity share taken up by estimated remediation is small — a favorable ratio for most property owners.

Median Home Value

$86,800

Est. Remediation

$400

Remediation as % of home value 0.5%

Remediation costs in Timber Lake are relatively low compared to home values. The $0–$800 estimated range is a small fraction of median property value. Home values are 50% below the South Dakota average.

Lead Exposure Risk for Children in Timber Lake

77%

Homes Built Before 1986

0.005

mg/L Avg Lead (Limit: 0.015)

Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.

Despite citywide averages serving as the standard public reference point, those aggregates cannot resolve what is happening at one specific faucet — and where 77% of Timber Lake homes come from before the solder rule or where utility samples sit at or above the action mark, the gap between system data and faucet reality matters more than it does in lower-exposure communities. An in-home draw closes that gap, with certified filtration through retailer networks available where confirmed faucet results warrant additional measures.

Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.