On-site sewage disposal systems are used in rural areas where houses are spaced so far apart that a sewer system would be too expensive to install, or in areas around cities where the city government has not yet provided sewers to which the homes can connect.
AFFECT is a verb, and means to influence or change.. EFFECT is a noun, and means the result, consequence, or change that is made. The two words are often confused, even moreso because effect can be a verb, rarely but noticeably used, specifically with the word change. If the word is used as an action, you will almost always use affect.
In simple terms, affect means 'make a difference to', whereas effect means 'a result' or 'bring about a result' here are some excerpts from a dictionary. AFFECT. To have an influence on or effect a change in: Inflation affects the buying power of the dollar. To act on the emotions of; touch or move.