diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index b2f90721e627dff8c318bde6007f9bdfbf6ca542..1139280571450d3294ac98975620355b997a441e 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -239,6 +239,9 @@ NSHM Tests:
       - CMD: testConus2023
       - CMD: testHawaii2021
   script:
+    - memory="$(free -g | awk '/^Mem:/{print $2}')";
+    - export CI_RUNNER_MEMORY="$(printf "%.f" "$(echo "${memory} * 0.90" | bc)")g";
+    - echo "${CI_RUNNER_MEMORY}"
     - ./gradlew ${CMD}
     - cat ${JACOCO_HTML_DIR}/index.html
   stage: test
diff --git a/gradle/nshm.gradle b/gradle/nshm.gradle
index 0aad9e2f57e6de4ba66c985e4ac0d5ecaa1cf227..6a761b87dd91dc32d73c04b098688df314c4d6bd 100644
--- a/gradle/nshm.gradle
+++ b/gradle/nshm.gradle
@@ -13,6 +13,8 @@ import org.yaml.snakeyaml.Yaml
 
 ext {
   nshmDir = "nshms";
+  envMemory = System.getenv("CI_RUNNER_MEMORY")
+  def xmx = envMemory ? envMemory : "16g"
 
   // Download and unzip NSHM
   downloadNshm = {nshm ->
@@ -92,7 +94,7 @@ task testAlaska2007(type: Test) {
   useJUnitPlatform()
   jvmArgs(
       "-Xms2g",
-      "-Xmx8g",
+      "-Xmx${xmx}",
       )
 
   filter {
@@ -116,7 +118,7 @@ task testAlaska2023(type: Test) {
   useJUnitPlatform()
   jvmArgs(
       "-Xms2g",
-      "-Xmx8g",
+      "-Xmx${xmx}",
       )
 
   filter {
@@ -140,7 +142,7 @@ task testConus2018(type: Test) {
   useJUnitPlatform()
   jvmArgs(
       "-Xms2g",
-      "-Xmx8g",
+      "-Xmx${xmx}",
       )
 
   filter {
@@ -164,7 +166,7 @@ task testConus2023(type: Test) {
   useJUnitPlatform()
   jvmArgs(
       "-Xms2g",
-      "-Xmx16g",
+      "-Xmx${xmx}",
       )
 
   filter {
@@ -188,7 +190,7 @@ task testHawaii2021(type: Test) {
   useJUnitPlatform()
   jvmArgs(
       "-Xms2g",
-      "-Xmx8g",
+      "-Xmx${xmx}",
       )
 
   filter {