The North Central District Health Department and Middle Niobrara Natural Resources District encourage area residents to have their water tested for nitrate levels.  Representatives on the KVSH Comment program stated that about 10 to 15 percent of the wells they test do have high nitrates. High level of nitrates in drinking water can affect all ages.  Pregnant woman are especially susceptible.  Exposure can also lead to thyroid disease, birth defects and increase risk of certain cancers. Nitrates are tasteless, colorless and odorless so the only way to detect them is by testing. The NRD office in Valentine offers free nitrate testing at their location on Highway 20 in Valentine. You can also send information to the State of Nebraska and ask for a free testing kit.  For more information call 402 376 3241.