Radon Mitigation in West Manheim Township, PA
Updated
PA DEP has 11,820 home radon tests on record from the ZIP code that cover West Manheim Township (17331). 47% came back at or above the EPA's 4.0 pCi/L action level, against 52.5% for York County as a whole. Lower than York County overall, yet still more than four tests in ten. A standard system here typically costs $800 to $1,500. The only way to know about one house is to test it.
West Manheim Township is a township in York County with about 9,839 residents and 4,003 homes, median year built 2002. It covers the area south of Hanover. The southwestern corner of Codorus State Park lies within the township. 47% of PA DEP radon tests in its ZIP codes came back at or above the action level, below the county's 52.5%.
What the PA DEP test records show for West Manheim Township
ZIP 17331 covers essentially all of West Manheim Township, so these numbers are about as local as public radon data gets.
| ZIP | Tests | Median pCi/L | 4+ pCi/L | 10+ | 20+ |
|---|---|---|---|---|---|
| 17331 | 11,820 | 3.6 | 47% | 22.9% | 12.4% |
| York County | 98,845 | 4.3 | 52.5% | 26.8% | 13.1% |
Look past the median to the high end. One test in 8 here came in at 20 pCi/L or more, five times the action level, and the highest reading on record is 1,260 pCi/L. Neighboring houses can differ by a factor of ten, so none of this tells you what your house is. It tells you the odds are high enough that a $15 to $30 test kit is worth buying.
Tests people chose to run, not a random survey. Details on the York County radon levels page.
Basement readings versus first-floor readings
In ZIP 17331, basement tests have a median of 4 pCi/L, while tests taken on the first floor have a median of 1.8 pCi/L (982 first-floor tests). The basement number runs 2.2 times the first-floor number, which is the usual pattern: radon comes up from the soil, so it is strongest at the lowest level and gets diluted as it moves up through the house.
Radon results by decade in ZIP 17331
| Decade tested | Tests | Median pCi/L | 4+ pCi/L |
|---|---|---|---|
| 1980s | 282 | 3.5 | 47.5% |
| 1990s | 1,600 | 4.3 | 52.3% |
| 2000s | 2,997 | 4.1 | 51.5% |
| 2010s | 4,430 | 3.6 | 47% |
| 2020s | 2,511 | 2.7 | 38.1% |
The share peaked in the 1990s at 52.3% and sits at 38.1% for tests since 2020. A drop that size is mostly about who is testing, not the ground. More recent tests come from home sales and from retests after a system went in, and both pull the share down. The rock under West Manheim Township has not changed. 2,511 tests have been logged in 17331 since 2020, so people here are still testing.
Housing in West Manheim Township and what it means for a system
Census Bureau, American Community Survey 2020 to 2024:
| West Manheim Township | York County | |
|---|---|---|
| Homes (housing units) | 4,003 | 189,857 |
| Median year built | 2002 | 1976 |
| Built before 1940 | 10.1% | 18.3% |
| Built before 1980 | 31.8% | 54.8% |
| Built 2000 or later | 56.4% | 20.6% |
| Single-family detached | 71.4% | 64.3% |
| Attached (rowhome, townhouse) | 21.1% | 17.1% |
| Mobile homes | 1.8% | 4.1% |
| Owner-occupied | 91.2% | 76.3% |
About 21.1% of homes here are attached: rowhomes, twins and townhouses. A shared wall does not stop radon, and neither does a neighbor's system, so each unit needs its own test. The tricky part is pipe routing, since there is often no side yard to run the vent up. Our rowhome radon guide covers how installers handle it.
56.4% of the homes here were built in 2000 or later, one of the higher shares in the county. New construction is not radon-proof. A tight modern house can hold radon in as well as it holds heat in. Some builders rough in a passive vent pipe during construction, which makes a later active system cheaper, so check for a capped pipe in the basement. More on that in radon in new construction.
Cost-wise, a newer house with a passive pipe already roughed in can come in under the usual $800 to $1,500, since the installer mostly adds a fan and a gauge. Full ranges on the cost page.
Where we work in West Manheim Township
Main roads include Route 94. Public schools here are part of South Western School District. The southwestern corner of Codorus State Park lies within the township.
Installers must hold a PA DEP radon mitigation certification (how to check), and permit questions go to the township office at www.westmanheimtwp.com.
Common questions
Is radon a problem in West Manheim Township?
Yes. PA DEP has 11,820 tests on record from the ZIP code covering West Manheim Township, and 47% of them came back at or above the EPA's 4.0 pCi/L action level. 12.4% were at 20 pCi/L or more. The county-wide rate is 52.5%.
What is the average radon level in ZIP 17331?
The median of 11,820 PA DEP tests in ZIP 17331 is 3.6 pCi/L and the mean is 10.1 pCi/L. A mean that far above the median means a long tail of very high readings, topping out at 1,260 pCi/L.
Nearby
Hanover 47%, Heidelberg Township 49.4%, Manheim Township 59.6%. Share of PA DEP tests at or above 4.0 pCi/L, against 47% here.
Have a test result from West Manheim Township?
Send us the number and the foundation type, or call and read it out.
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