It's recommended to sync instead of import these feeds into your calendar.
How to Sync iCal Feeds with Google Calendar:
- Right click on the applicable iCal link above and select "Copy Link Address".
- With Google Calendar open, on the left hand side under other calendars, click on the drop down arrow.
- Click on Add by URL.
- Paste the iCal link into the box.
- Click Add Calendar.
- Once Google Calendar syncs the subscription, it will appear on the left side.
- Locate the Calendar on the left side (it will be a long URL address), and click "calendar settings" under the URL name.
- You can then change the name of the calendar (this is located near the top of the page).
- Navigate out of Settings using the arrow in the top left corner.
- You will now be able to toggle on/off the display view of this calendar and it will be listed in your calendar feed.
How to Sync Google Calendar with a phone or tablet