Maven appears to be ignoring source and target in webapp

Maven appears to be ignoring source and target in webapp

I'm getting "Generated servlet error:|try-with-resources is not supported
in -source 1.5". 1.5 is maven's default according to another question on
the topic, but I thought I had fixed that in my pom.xml -
<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd"
xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>com.sspo</groupId>
<artifactId>sspo-parent</artifactId>
<version>1.0-SNAPSHOT</version>
</parent>
<artifactId>website</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>war</packaging>
<name>website</name>
<properties>
<jetty.version>9.0.5.v20130815</jetty.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
<plugin>
<groupId>org.eclipse.jetty</groupId>
<artifactId>jetty-maven-plugin</artifactId>
<version>${jetty.version}</version>
<dependencies>
<dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>20030825.184428</version>
</dependency>
<dependency>
<groupId>commons-pool</groupId>
<artifactId>commons-pool</artifactId>
<version>20030825.183949</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.26</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>com.sspso</groupId>
<artifactId>com.sspo.package1</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>com.sspo</groupId>
<artifactId>com.sspo.package2</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
<scope>provided</scope>
</dependency>
</dependencies>
</project>
Other packages in the project work fine with 1.7, as seen in the parent pom -
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.sspo</groupId>
<artifactId>sspo-parent</artifactId>
<packaging>pom</packaging>
<version>1.0-SNAPSHOT</version>
<name>sspo-parent</name>
<modules>
<module>try-with-resources-works-here</module>
<module>and-here</module>
<module>even-in-this-one</module>
<module>website</module>
</modules>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>14.0.1</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.2</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.14</version>
</dependency>
</dependencies>
</project>
Ultimately, I think the question is probably "what have I done wrong that
maven is ignoring the source and target specifications?" There are similar
questions out there, but the ones I've seen are either not solved or
suggest things that exist in my pom.
Any help would be appreciated.