diff --git a/mmv1/third_party/terraform/.teamcity/components/projects/reused/nightly_tests.kt b/mmv1/third_party/terraform/.teamcity/components/projects/reused/nightly_tests.kt
index cb6455e5f752..75fd33a9d529 100644
--- a/mmv1/third_party/terraform/.teamcity/components/projects/reused/nightly_tests.kt
+++ b/mmv1/third_party/terraform/.teamcity/components/projects/reused/nightly_tests.kt
@@ -51,7 +51,7 @@ fun nightlyTests(parentProject:String, providerName: String, vcsRoot: GitVcsRoot
         else -> throw Exception("Provider name not supplied when generating a nightly test subproject")
     }
     val serviceSweeperConfig = BuildConfigurationForServiceSweeper(providerName, ServiceSweeperName, sweepersList, projectId, vcsRoot, sharedResources, config)
-    val sweeperTrigger  = NightlyTriggerConfiguration(startHour=12)  // Override hour
+    val sweeperTrigger  = NightlyTriggerConfiguration(startHour=11)  // Override hour
     serviceSweeperConfig.addTrigger(sweeperTrigger)
 
     return Project {
diff --git a/mmv1/third_party/terraform/.teamcity/tests/sweepers.kt b/mmv1/third_party/terraform/.teamcity/tests/sweepers.kt
index 67940004bc68..d6805843a39c 100644
--- a/mmv1/third_party/terraform/.teamcity/tests/sweepers.kt
+++ b/mmv1/third_party/terraform/.teamcity/tests/sweepers.kt
@@ -7,12 +7,14 @@
 
 package tests
 
+import ProjectSweeperName
 import ServiceSweeperName
 import jetbrains.buildServer.configs.kotlin.BuildType
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertTrue
 import org.junit.Test
 import jetbrains.buildServer.configs.kotlin.Project
+import jetbrains.buildServer.configs.kotlin.triggers.ScheduleTrigger
 import org.junit.Assert
 import projects.googleCloudRootProject
 
@@ -102,4 +104,50 @@ class SweeperTests {
         val value = sweeper!!.params.findRawParam("PACKAGE_PATH")!!.value
         assertEquals("./google-beta/sweeper", value)
     }
+
+    @Test
+    fun projectSweepersRunAfterServiceSweepers() {
+        val project = googleCloudRootProject(testContextParameters())
+
+        // Find GA nightly test project's service sweeper
+        val gaNightlyTestProject = getSubProject(project, gaProjectName, nightlyTestsProjectName)
+        val sweeperGa: BuildType? = gaNightlyTestProject!!.buildTypes.find { p-> p.name == ServiceSweeperName}
+        if (sweeperGa == null) {
+            Assert.fail("Could not find the sweeper build in the Google (GA) Nightly Test project")
+        }
+
+        // Find Beta nightly test project's service sweeper
+        val betaNightlyTestProject = getSubProject(project, betaProjectName, nightlyTestsProjectName)
+        val sweeperBeta: BuildType? = betaNightlyTestProject!!.buildTypes.find { p-> p.name == ServiceSweeperName}
+        if (sweeperBeta == null) {
+            Assert.fail("Could not find the sweeper build in the Google (Beta) Nightly Test project")
+        }
+
+        // Find Project sweeper project's build
+        val projectSweeperProject: Project? =  project.subProjects.find { p->  p.name == projectSweeperProjectName}
+        if (projectSweeperProject == null) {
+            Assert.fail("Could not find the Project Sweeper project")
+        }
+        val projectSweeper: BuildType? = projectSweeperProject!!.buildTypes.find { p-> p.name == ProjectSweeperName}
+        if (projectSweeper == null) {
+            Assert.fail("Could not find the sweeper build in the Google (Beta) Nightly Test project")
+        }
+
+
+        // Check only one schedule trigger is on the builds in question
+        assertTrue(sweeperGa!!.triggers.items.size == 1)
+        assertTrue(sweeperBeta!!.triggers.items.size == 1)
+        assertTrue(projectSweeper!!.triggers.items.size == 1)
+
+        // Assert that the hour value that sweeper builds are triggered at is less than the hour value that project sweeper builds are triggered at
+        // i.e. sweeper builds are triggered first
+        val stGa = sweeperGa!!.triggers.items[0] as ScheduleTrigger
+        val cronGa = stGa.schedulingPolicy as ScheduleTrigger.SchedulingPolicy.Cron
+        val stBeta = sweeperBeta!!.triggers.items[0] as ScheduleTrigger
+        val cronBeta = stBeta.schedulingPolicy as ScheduleTrigger.SchedulingPolicy.Cron
+        val stProject = projectSweeper!!.triggers.items[0] as ScheduleTrigger
+        val cronProject = stProject.schedulingPolicy as ScheduleTrigger.SchedulingPolicy.Cron
+        assertTrue("Service sweeper for the GA Nightly Test project is triggered at an earlier hour than the project sweeper", cronGa.hours.toString() < cronProject.hours.toString()) // Values are strings like "11", "12"
+        assertTrue("Service sweeper for the Beta Nightly Test project is triggered at an earlier hour than the project sweeper", cronBeta.hours.toString() < cronProject.hours.toString() )
+    }
 }