Kristina Hill says she completely understands why the Oakland A’s and the City of Oakland have settled on the Howard Terminal site as the future home of the Major League Baseball team in the East Bay.

The UC Berkeley associate professor of environmental design warns, however, that the project won’t be easy — and not just because the ground there has a history as an industrial site and has lots of chemicals that have to be expunged from the earth before building can begin.

Howard Terminal, just north of Jack London Square, is right up against the Oakland Estuary. The A’s and the Oakland consider that an asset. But with climate change leading to rising waters globally, including San Francisco Bay, that’s going to be a problem, says Hill, whose research delves into coastal design and its problems in the Bay Area.

The A’s and their Danish designer, Bjarke Ingels Group (BIG), could, in fact, build a wall. Hill, who was part of the team that designed New Orleans’ water strategy post-Hurricane Katrina, expects they are already planning on doing so.

Dave Kaval, the A’s president and the point man on the stadium, agrees sea level rise will be an issue and says that has been factored into the plans announced Wednesday.

“We’ve done extensive testing on the site,” Kaval says. “And we’re going to have to raise the site by 3½ feet to accommodate the 2100 tide event. That’s part of our infrastructure.”

Hill, however, says that’s the easy part. The water problems with the site go deeper than that.

Actually, it’s lack of depth that’s the problem. Hill says that groundwater under the site floats on top of sea water. As sea water rises, so does the groundwater.

“You can build a wall to keep the sea water out and the waves down, but we have done studies in that area, and the groundwater is rising both north and west of Howard Terminal,” Hill says. “And as problematic as the rising of sea level is, there is much more to consider with the groundwater level.

“There is legacy contamination in the areas where they will be building,” she explains. “That’s been capped, but generally those doing the capping haven’t lined it from below. And that means when the groundwater comes up, those contaminants can be remobilized.”

Kaval, who came to his current post from being the head man with soccer’s San Jose Earthquakes, doesn’t see that as an issue in the same way that Hill does.

“We had some issues like that when we built Avaya (Stadium, the Earthquakes’ home),” he said. “Down there, the former owners, FMC, filtered the water. There are ways to do that. We’ll have to do testing to see if it’s necessary. It’s something to be studied.”

From Hill’s viewpoint, dealing with the impact of rising groundwater is absolutely necessary. The failure to do so, she says, means toxic contaminants could resurface with the help of the groundwater and be an ongoing problem during construction and throughout the A’s tenure.

The San Francisco Bay Conservation and Development Commission, which addressed issues of rising sea levels before signing off on the Golden State Warriors’ new arena at Mission Bay, will have to sign off on this project as well.

With the arena, which is due to welcome the Warriors next year, specifications called for the ground to be elevated to levels that would avoid inundation during a 100-year storm and up to 66 inches of sea level rise.

Hill was impressed that the A’s turned to BIG to do the design, saying they “aren’t the cheapest by a lot, they do good and innovative work and they know coastal design.” Denmark is nothing if not coastline.

One problem facing BIG and the A’s is that until recently the company hadn’t worked in the U.S. all that much, with the exception of the World Trade Tower 2, a building in New York City that has been put on hold since the prospective primary tenants, 21st Century Fox and News Corp, reversed their original decision to move into the new structure. BIG is working on a new Google campus in Sunnyvale and has a proposal to protect coastal areas near San Francisco’s Islais Creek from climate change-induced flooding.

“They (BIG) know about coastal design, but they have mostly worked in Europe and they may not have had to work with this kind of issue,” she says. “Europe hasn’t done as much as the U.S. to monitor water quality. It has done more in isolating and removing contaminated soils. So European firms may not have had to think as much about how rising groundwater could remobilize wastes.

“They are new to stadium building, and unless they’re planning on building a floating stadium, they better have an idea of how to handle rising sea level. They will elevate the area. I see where they are planning access by gondola (an overhead tram from BART). If they do that, they won’t have to care if the roads flood.”

Come again? Roads will be flooding? Well, Hill says that some Bay Area roads, including Highway 37 in the North Bay and the Marin entries to Highway 101 already flood at king tides (the highest of high tides). New stadium or not, more Bay Area roads will have to deal with flooding as sea levels rise because of climate change in years to come.

“Groundwater is pretty shallow under much of West Oakland,” Hill says. “Right now, northbound lanes of I-880 are only about a foot higher than the groundwater level at king tides. With a big rain and high tides, you could get some flooding now.”

A stadium could exacerbate the problem, the weight of the building compressing and lowering the ground level, leading Hill to underscore the importance of elevating the area.

There is always the issue of liquefaction of the ground in case of earthquake, too, because fill on top of wetland historically reduces the strength and solidity of soil when quakes come.

“I hope they will be thinking about that,” Hill says. “The new Apple headquarters in the South Bay dealt with that with a floating foundation. That’s something that may be looked at. Problems only get worse as the soil gets wetter. But on a former wetland, if you remove too much of the water, then you’re looking at a collapse. That’s what happened in New Orleans. It’s a wicked problem.”

“It’s a tough site. But I can see why they’d want to be downtown and close to the water. I understand that. Dealing with the groundwater won’t be easy.”

The A’s plan also sets forward the idea of redesigning the ball club’s current home, the Coliseum at 66th Avenue and I-880. Hill has looked at the project and so far hasn’t seen water levels being taken into account as the site gradually is repurposed for residential housing, parks and businesses.

“The mayor (Libby Schaff) mentioned that the design addressed sea level rise, but I don’t see that,” Hill says. “I agree we need more residential housing, but at the same time we have to protect people’s houses from flooding. There are two creeks at the site, both of which branch off, so there are actually four creeks. That all has to be taken into consideration.”

Kaval says such consideration is being given.

“In terms of rising sea level, the Coliseum is actually tougher to deal with,” he says. “For one thing, it has a lower elevation, and then there are the creeks. One of the reasons we are incorporating a large park and restored wetlands is so that we can accommodate sea level rise. We want to be a steward of the area.”