Our Firm

Through the years, the firm has maintained its focus on urban design, land planning, and landscape architecture while retaining close ties with clients and consultants.


MGB+A has over 50 years of experience with projects involved in planning, design, and many other endeavors relating to man’s interaction with his environment. The firm of Maas and Grassli Landscape Architects was originally founded as a partnership in 1959 and then became a corporation in 1973. In 1980, the firm relocated the office headquarters from Ogden to Salt Lake City, Utah and became MGB+A.


Our Firm has, over the years, gained recognition for our design and planning abilities. We have proudly established and maintained a reputation for our ability to satisfy the desires and interests of our clients with sound planning and design principles. The members of MGB+A have considerable experience in a wide range of projects throughout the United States, South America, and Europe, providing a substantial knowledge base for innovative design solutions.


An integral part of our design process is the creative interaction between client, planning team, and project user. Continuous involvement of the client in the project from its initial stages through final design assures a gratifying solution based on client needs. On all projects, a principal or associate is selected as project manager to oversee administrative matters, organization, and quality control. The entire staff acts as an in-house design review to ensure the client receives a quality product. 



Provide quality, creative services to meet or exceed the needs and desires of the client while upholding our professional responsibilities to the community, the environment, and the art of Landscape Architecture.


























Jay Bollwinkel, ASLA, PLA, AICP, LEED ND - Principal

Mr. Bollwinkel manages complex projects from marketing, client relations and contract negotiation, through the design and construction document phase. Construction coordination is one of his strengths, emphasizing quality in construction installation techniques to achieve landscape architectural design intent. Mr. Bollwinkel excels in the realms of regional and city planning. He has participated in public workshops, such as Envision Utah, directing neighborhood groups and governmental agencies through complicated public input processes relating to controversial projects. He is an effective group facilitator and understands the importance of integrating opposing viewpoints into a consensus solution. Mr. Bollwinkel has also served his professional colleagues as a former president of the Utah Chapter of the American Society of Landscape Architects and various other community service organizations.



Greg Boudrero, ASLA, PLA - Principal

Greg has a strong passion for design and is driven to bring a unique level of quality and attention to detail to his projects.  He enjoys collaborating with multi-disciplinary teams and understands that the best solutions come from an open design process.  His work has included institutional plazas and courtyards, urban plazas and streetscapes, gardens, and parks.

Greg excels at portraying two-dimensional and three-dimensional project themes with his graphic and visualization skills.  His direct and personal communication with clients leads to strong relationships and successful projects while inspiring loyalty in many of our clients.



Dan Sonntag, ASLA, PLA - Associate

Dan Sonntag is an award winning Landscape Architect with expertise in Recreation Planning, Residential Estate Master Planning, Park and Open Space Planning, Wetland Mitigation, and Sustainable Stormwater Management.  His graduate work focused on watershed stewardship wherein he worked with a multidisciplinary team to develop a watershed management plan for a rural area in central Pennsylvania being affected by polluted runoff from abandoned coal mines.  Mr. Sonntag also has published research regarding critical analysis of wetland mitigation projects.  Mr. Sonntag brings many skills to the table including strong design ability, construction knowledge, graphic communication, and riparian habitat knowledge. 


Leonard Grassli, FASLA - Principal Emeritus

Mr. Grassli is the founding principal of MGB+A, and is involved with the project development in the firm as well as the business management. He develops design concepts, coordinates with clients and reviews projects through completion. During his 50 years of professional experience Mr. Grassli has participated in a wide variety of projects and in both the public and private sectors.  He is an expert in working with city, county and state government staff and he has participated in many public meeting and charettes for public projects.  One of Mr. Grassli's strengths is his Swiss training and professional experience that favors his innovative ideas and helps create design solutions that are both aesthetic and functional.  In 1997 he was awarded the prestigious honor of Fellow by the American Society of Landscape Architects. 


On the Boards Thanksgiving Point


The following are current MGB+A Projects.


111 South Main

Abravanel Hall Plaza

Artspace - Macaroni Flats

Concepcion Chile LDS Temple

Daybreak Brookside Pool

Eagle Mountain Midvalley Park MP

Eccles Performing Arts Theater

Edwards Lifesciences

Elko Sports Complex

Farmington Office Complex

Grant Avenue Promenade

Ivins City Center MP Update

Jordan River - 900 South Oxbow

Lisbon Portugal LDS Temple

Litle Residence

Millcreek Park Bountiful

Moab Lions Park

Murray Downtown Development

OC Tanner Plaza

Park City 2015 Streetscape Improvements 

Red Butte Gardens Conservation Garden

Redwood Road Corridor Study - West

Rexburg Downtown Redevelopment

SLC Regional Athletic Complex

St. George Millcreek Park

Taylorsville City Hall

Tijuana Mexico LDS Temple