Two groups seeking to renovate KeyArena for NBA and NHL use say there’s ample parking within a mile of the venue — which they would help patrons locate while also improving alternative means of getting them to and from games.

A pair of half-billion-dollar proposals submitted last month by Oak View Group (OVG) and Seattle Partners (SP) — and made public by the city of Seattle on Monday — are heavy on technology to assist patrons in navigating the drive and finding available parking spaces. The proposals also suggest expanding or supplementing the Monorail beyond current capacity and facilitating nearby bus, shuttle, Uber and Lyft rides while improving the walking and bicycle access from local streets.

The basic premise of both groups is similar — expanding the parking perimeter to include more spots — but their investment strategies differ.

Seattle Partners envisions using Westlake Center as a key arrival and departure point and has pledged spending up to $1.5 million on two transportation “mobility hubs” to bridge the final mile-long distance between it and the venue.

OVG has targeted a shorter, three-quarter-mile radius from the venue for locating additional parking. It also plans to build an 850-stall parking garage next to the arena, but only if it first secures public funding via the Port of Seattle.

“Expanding the available parking supply to within a 15-minute walk (approximately three-quarters of a mile) of (the arena) increases the available parking supply by over 3,200 parking stalls for a total of 11,350 stalls,” the 109-page OVG proposal states.

The group adds that the 11,350-stall figure within the three-quarter-mile radius is nearly double the 6,100 car parking spaces needed to accommodate a large Key­Arena event exceeding 10,000 patrons. It says an additional 2,400 stalls can be added by expanding another quarter-mile out to Westlake Center, where patrons could then jump on an expanded Monorail service.

OVG plans deals with local parking garages and would create a mobile app that patrons could use to locate and pay for available stalls in advance.

On the Port’s potentially helping finance its parking garage, OVG spokesman Lance Lopes said: “We will work with the city to try and obtain a Port contribution for what we see as a part of a regional transportation solution.”

Seattle Partners would invest in “mobility hubs” to connect patrons between Westlake Center and Key­Arena. Mobility hubs combine multiple means of transit — including busses, light rail, taxis and shared rides — into a centralized pick-up and drop-off location.

SP is planning for patrons to park near Westlake Center, or arrive via light rail and then access multiple transit options to complete the “last mile” journey to a new mobility hub near KeyArena.

SP would spend $5 million to expedite existing city mobility programs, including up to $1 million on financing of the KeyArena mobility hub — near a new light-rail station planned for 2035 — while supporting transit from the existing Westlake Center hub.

“For most event goers, a transfer is needed to make the last mile connection to the site,” the 691-page SP plan states. “Without seamless modal integration, these transfers will be a major barrier to taking transit to the area.”

OVG says it also would help the city coordinate and facilitate transit options at the Westlake Center hub — including an expansion of the Monorail platform so it can handle up to 5,000 riders per hour in one direction. It wouldn’t build a second hub near KeyArena but would have a nearby “drop off zone” for taxis, ride services and shuttles.

Both plans were turned in to the city April 12.

OVG says it can have the arena ready by Oct. 1, 2020, and SP is targeting March 1, 2021 — though both dates would be subject to delays in getting the go-ahead. Both construction plans conflict with recently announced opening-round games of the NCAA men’s basketball tournament at KeyArena in March 2019.

Though OVG CEO Tim Leiweke has suggested moving the tournament dates to a different year so it can be played once the arena is remodeled, SP spokesman Aaron Pickus said his group has no problem beginning construction after the tournament ends and finishing the remodel later.

OVG has a $564 million renovation proposal financed with $414 million down and an additional $150 million in loan money from Goldman Sachs — with an opportunity for $200 million to $250 million in additional loans from the investment bank if NBA and NHL teams are acquired.

The $521 million SP renovation plan calls for $271 million in private funds down and $250 million in public-bond funding. By using the lower-interest municipal bonds, SP says it would save $47.8 million in financing costs and bring the city excess revenues totaling $144 million over the 35-year lease term.

Both plans eye expanding sponsorship and opportunities throughout the Seattle Center campus.

A city advisory panel and executive staffers were given private presentations by both groups last week and will now pore over details. A recommendation is to be made to Mayor Ed Murray by late June, after which he’ll decide whether to forward any accepted proposal to the City Council.

The council also is considering a revised, all-private arena plan by entrepreneur Chris Hansen for the Sodo District and likely would choose between that and a KeyArena remodel for NBA and NHL use. Hansen’s plan is contingent on first getting teams to commit to Seattle. Both KeyArena groups say they would build immediately without teams.

Traffic and parking are hot topics in the arena debate and something the KeyArena groups were required to address in proposals.

OVG hired the Seattle office of Parametrix to work on its transportation plan. That’s the same company Hansen used to conduct his Sodo traffic study.

SP partnered on its transportation plan with the NelsonNygaard firm.

The walk of approximately 15 minutes outlined in OVG’s expanded parking plan is comparable with about a 13-minute walk from the nearest light-rail station in Sodo to the site of Hansen’s planned venue.

SP would initiate a program that encourages patrons to enjoy restaurants and bars pregame and postgame in the Westlake Center and Uptown neighborhoods. Fans could park near Westlake and use the mobility hub to get to the arena, and those in Uptown could walk or ride to the site via improved east-west pedestrian access and bicycle facilities on local streets.

Both groups would implement a bolstered Monorail — with OVG initiating talks to expand the platform and boost ridership capacity from 2,700 people per hour up to 5,000 in a single direction by enabling multiple-car boarding. OVG has explored integrating the Monorail fare into the ORCA pass system and cost of a game ticket while facilitating access to the platform from the Westlake light-rail stop to make for a more seamless transition.

SP also has begun talks to “maximize” existing Monorail capacity during game days and expand service by running a simultaneous shuttle to and from the arena. It also would incorporate Monorail fares into event tickets, make it compatible with the ORCA system and improve access from the light-rail tunnel. SP also plans to partner with local hotels to provide free ORCA cards to guests.