VANCOUVER -- A collision near a Metro Vancouver ferry terminal impacted traffic and service for several hours Monday.

The three-vehicle head-on crash was reported around 9 a.m. Monday, and the road was not fully re-opened until shortly before 3 p.m.

In a message posted on Twitter, the Delta Police Department's traffic unit announced that a truck had de-iced the stretch of Highway 17, the vehicles involved in the crash had been towed, and all lanes were once again open to traffic.

The crash happened just outside BC Ferries' Tsawwassen terminal. Few details have been provided about the collision, but the traffic unit said someone was seriously injured.

The reason behind the hours-long delay was a need to fully document the scene for an investigation, and to make sure the road was safe for drivers after it had been cleared, Delta PD said.

The Spirit of Vancouver Island was held at the dock Monday morning as a result, BC Ferries said, and passengers were kept on the vessel for some time.

The vessel had been travelling between Swartz Bay and Tsawwassen.

A single lane of alternating traffic was open to help clear passengers from the area, and let those waiting for later ferries through, but delays were reported on several sailings and congestion was bad enough that two trips were cancelled because a crew member was stuck in traffic.

"Customers travelling to and from Tsawwassen are being advised that they may experience a delay in accessing or leaving the terminal," BC Ferries said in an advisory about the incident.

"Every effort will be made to ensure reserved customers will have their reservations honored on the next available sailing once they arrive to the terminal."

BC Ferries advised customers that further updates would be posted on its Current Conditions page.

It appeared the crash was affecting service between the terminal and Victoria, Nanaimo and the Southern Gulf Islands.

At 10:45 a.m., BC Ferries posted the Salish Orca was among the vessels impacted. The ferry between the mainland and the Southern Gulf Islands was 21 minutes late due to the crash, an advisory said.

Throughout the road closure, the Coastal Celebration (Tsawwassen to Swartz Bay) and Queen of Alberni (Tsawwassen to Nanaimo) were also impacted.

And, as previously mentioned, two sailings were cancelled due to the crash. A staff member couldn't get to the vessel (the Coastal Renaissance) on time due to congestion in the area as a result of the crash, so the 11 a.m. trip from Tsawwassen and the 1 p.m. sailing back from Swartz Bay were cancelled.

Unrelated to the crash, 10:40 a.m. trip from Horseshoe Bay to Nanaimo was 65 minutes late due to a frozen berth. The vessel, Queen of Coquitlam, had to shift to another berth.

Tweets from Delta police sympathized with those who had missed their ferry or were stuck near the scene, but said weather had played a role in what was investigators "one chance" to document the scene.

"A collision reconstructionist is on scene and must gather evidence, such as measurements, photos etc. that could be relevant to the cause of the crash and contributing factors," Delta PD's traffic unit posted on Twitter Monday afternoon as part of a reminder that the crash was serious, and must be investigated.

"Unfortunately conditions are quire challenging at the scene, and this has contributed to time investigators require. But please be assured that our investigators are working as quickly as possible, while other officers are assisting in getting traffic through in a limited fashion."

Police have not yet provided a possible cause of the crash, saying any comment would be "sheer speculation." The forecast suggested it was -6 C and lightly snowing in Tsawwassen Monday morning.

Transit users also had issues getting to and from the terminal, as buses were experiencing delays.

Some bus passengers reported delays on the 620 bus at Ladner Exchange, while others were waiting at the ferry terminal.

"There's a mass of people and babies freezing and requiring transport out from the terminal," said one transit user on Twitter to TransLink. "Another ferry arrived with even more people. You will need extra buses to clear the backlog."

TransLink posted on Twitter that the 620 Bridgeport Station bus wouldn't be travelling between the terminal and Ladner Exchange. The detour was cleared within the hour, but transit officials warned passengers to expect residual delays.

The latest service disruption was likely not welcome news to travellers trying to reach their destinations after three days of cancelled sailings. Thousands were stranded over the weekend with more than a dozen sailings cancelled due to weather.

.@deltapolice much closer to the clearing stages of this nasty collision on Hwy 17 near the Tswn Ferry Terminal. Feeling bad for all the ferry passengers that just can’t catch a break this week. Tows hooking up now, then the deicing trucks will do their thing and we will reopen pic.twitter.com/FF7X40PhD3 — Delta Police Traffic Unit (@DPDTraffic) January 13, 2020

There's a mass of people and babies freezing and requiring transport out from the terminal. Another ferry arrived with even more people. You will need extra buses to clear the backlog. start communicating so people can seek shelter in the terminal & come out only when bus arrives — avrilbowie (@avrilbowie) January 13, 2020

#RiderAlert 620 Bridgeport Station detour. Service omitting portion from Tsawwassen Ferry to Ladner Exchange due to motor vehicle accident.^jd — TransLink BC (@TransLink) January 13, 2020