Illustration of the concept of a maximal diagonal.  A maximum on this dimension is intended as a check on chunky buildings.

So what kind of growth was Greden talking about?

Greden meant more residents, businesses and buildings in downtown Ann Arbor.   Management of that growth is the goal of the A2D2 zoning revisions and the revised downtown plan that planning commission approved last week (March 3), and which  council was starting to work through on Monday night. Planning commission had previously approved a set of A2D2 zoning revisions back in late summer of 2008, but had been requested by city council to take another look at their proposed revisions.

That request resulted in a series of fall workshops led by city planner Wendy Rampson to solicit additional feedback on planning commission’s proposed revisions. Planning commission had undertaken that work based on recommendations approved by city council in November of 2007. And those recommendations had emerged over the course of a process that has now been at least four years in the making, dating back to the Calthorpe report.

Wendy Rampson led off Monday’s work session by tracing through the impetus behind the re-examination of Ann Arbor’s downtown zoning and planning, which came in the early 2000s in connection with the Ashley Mews construction and what she described as a residential building “boomlet.” The downtown plan, she said, was first adopted in 1988 and last updated in 1992, so it was due for an update, while the underlying zoning regulations had been in place since the 1960s, and were overdue for revision.

The recommendations to city council just approved by planning commission do not reflect an end to the public process.  Rampson outlined the following timeline for opportunities to weigh in before council is expected to reach a final decision:

• Monday, March 23: city council will hold a public comment session solely on the topic of the A2D2  zoning revisions and the downtown plan
• Monday, April 6: city council regular meeting, first reading of zoning revisions
• Monday, April 20: city council regular meeting, public hearing on the revised downtown plan with final vote
• Monday May 4: city council regular meeting, second reading of zoning revisions with final vote

As reflected in the timeline, the downtown plan has a different status from the zoning revisions. The zoning revisions require a change to the city’s ordinances, and thus require a first and second reading at council. The downtown plan, in contrast, is a planning document, which is part of the city’s master plan, which the state of Michigan requires to be adopted by both planning commission and city council.

If  city council amends the zoning recommendations from planning commission, the zoning as amended would become law. But if city council amends the planning commission recommendation for the downtown plan, the amended plan would then go back to planning commission for consideration by that body.

Rampson said that planning commission felt that the downtown plan was a sound document, even if it was a bit  heavy on narrative. The amendments to it, she said, reflected a tightening up of the narrative, plus material on future land use and a zoning plan, which are elements required by the state. The draft of the downtown plan approved by planning commission and which council was examining during its Monday (March 9) work session can be downloaded here: Ann Arbor Downtown Plan [3MB .pdf]

The revisions to the zoning ordinances for downtown in the form council received them from planning commmission can be downloaded here: Ann Arbor Downtown Zoning [1MB .pdf] This is a red-lined document, with the indicated changes reflecting differences between (i) the version of proposed zoning approved by planning commission  in September 2008, and (ii) the version of proposed zoning approved by planning commission on March 2, 2009.

An accompanying memo from planning commission helps navigate through the changes made since fall 2008, and provides insight into why some sections were not changed. Inasmuch as this memo provides response to the feedback heard through fall 2008 resulting from Rampson’s series of workshops, we include the better part of that memo at the bottom of this article.

The Basic Concept and Council’s Work Session Discussion

With Monday’s working session, city council has just begun its current round of work, but based on watching their discussion Monday night on CTN, planning commissioner Eppie Potts said she was encouraged that councilmembers were asking good questions. This, after she expressed her frustration at the conclusion of  planning commission’s March 2 meeting, saying that the newly proposed zoning did not do the job of improving downtown and its surroundings. Her criticisms included the lack of an adequate buffer for residential areas, and what she sees as conflicts between character overlays and the new zoning, plus a lack of specific green space.

So what were some of the good questions that councilmembers were asking?

Basics: The basic concept for the rezoning strategy that was passed most recently by planning commission remains intact from September 2008. Under the strategy approved by planning commission, downtown zoning is simplified to one of two districts: D1 (core) and D2 (interface). The D1 area is a contiguous area in the center of downtown, while D2 areas provide a buffer between the single D1 districts and residential areas. On top of these D1 and D2 districts are overlaid eight “character” districts, which identify unique aspects of the following areas: South University, State Street, Liberty/Division, East Huron, Midtown, Main Street, Kerrytown, and First Street.

One key difference between D1 and D2 areas is that building height is controlled purely with floor area ratio (FAR), while in D2 areas, it’s controlled through a combination of FAR and an absolute building height limit (60 feet) that applies independently of FAR and any bonus premiums.

D1 – Core
• 400% FAR by right
• 700% FAR with premiums
• 900% FAR with on-site affordable housing
• No absolute height limit (except in South University character district)

D2 – Interface
• 200% FAR by right
• 400% FAR with premiums
• 60 ft. height limit
• 80% lot coverage limit

South University: The one important exception to D1′s lack of absolute height limits is the South University character district. For South University, which is proposed as a D1 district, an absolute height limit is proposed at 170 feet. In the September 2008 proposal that planning commission approved, the South University absolute height limit had been set at 120 feet. In recent planning commission deliberations, the 170 feet for South University reflected a compromise that included the addition of a 30-foot setback for new construction from residential areas, plus a maximal tower diagonal on the building of 150 feet.

Current zoning in the South University area has no absolute height limits. Part of the South University area was rezoned in fall of 2006 by city council from a variety of different kinds of districts (campus business/residential, office, multiple-family dwelling) to a central business district and parking district.

It was that rezoning, together with an accumulation of parcels, that enabled the proposal for 601 S. Forest as a by-right  development at a height of 164 feet. [Recent reporting by Dan Meisler, writing for the Ann Arbor Business Review, lays out recent legal wrangling among the developers on that project.]

While there is a prominent D2 area proposed on the west side of the city, and a smaller D2 area on the southern edge, it’s not the case that D2 areas buffer the D1 core on all sides – South University is one of those areas without a D2 buffer. During council discussion at its Monday night work session, councilmember Margie Teall asked why the South University area did not include a D2 interface buffer.

Rampson noted that the real focus of increased density was meant to be along South University Avenue itself, and that part of the rationale for including the rest of the area was based on its zoning history before the 2006 rezoning. Given that the zoning history was “a material impetus in driving the decision” to zone the area as D1, councilmember Christopher Taylor wanted to know if that was a paper history or if it was reflected in the buildings that had actually been built. In response to Taylor’s question, Rampson suggested the “Stegeman Building” [1113 Willard, constructed in 1999 as "Willard Street Apartments"] and the Forest Avenue parking structure as examples.

Taylor’s concerns about the South University area pre-dates his service on council. After he had won the August 2008 Democratic primary, but before he was seated on council, Taylor spoke during a public hearing on the 601 S. Forest project, expressing concerns about the scale of that development.

Teall seemed unconvinced by Rampson’s explanation that in the South University area a D2 buffer was not feasible given the small size of the resulting D2 district. Teall cited the small D2 areas along William Street, suggesting that similar small D2 areas might be possible in the South University area. Rampson noted that one difference between South University and the William Street area was that the D2 area along William Street was a historic area.

Absolute Height Limits: Councilmember Greden took the first leap into the discussion of absolute height limits, not just for the South University character district, but also for other D1 areas. He said he would be paying very close attention to the possibility of a reasonable height limit that still respected the need for growth. Greden at one point mooted the idea of using character districts throughout D1 as the basis for different absolute height limits.

Asked by Greden for comment, Rampson said that when asked, “If there were an absolute height limit, what would it be?” the planning commission was at pains to name a number. She noted that the number in the original recommendations considered by council in 2007 – which provided the basis for planning commission’s work on the actual zoning language – was 240 feet.

That 240-foot limit was struck from the recommendations during council deliberations on Oct. 15, 2007. Bob Johnson first introduced a motion for an amendment to reduce the maximum height in the core area from 240 feet to 190 feet. That motion failed on lack of a second. Lowenstein then introduced an amendment completely striking the height limit of 240 altogether. That amendment succeeded with two votes against it – from mayor John Hieftje and Johnson.

[Editorial aside: The Chronicle's came across this episode while looking for support for statements made by Hieftje during the 2008 campaign, and as recently as last Sunday's council caucus, to the effect that there'd been an occasion when he had been the only vote for height limits. The Chroncile could not find an episode in the archives of council minutes fitting the description. When asked if the Oct. 15, 2007 meeting was the occasion to which he'd been referring (it's very close to matching the description), Hieftje wrote that his memory of the various meetings had grown "foggy," that Johnson had introduced his motion because Hieftje had asked him to, and that since that time several councilmembers had come around to his own point of view on height limits.]

Council’s interest as a body in exploring the question of absolute height limits can be seen in a June 2008 resolution passed by council to extend a deadline for completing of the A2D2 work: “RESOLVED, that City Council ask that the A2D2 Steering Committee look closely at the D1 core zoning and return with a recommendation that will address appropriate height and massing and provide examples for 150 ft. and 180 ft.”

At the working session on Monday, councilmember Tony Derezinski, who is city council’s representative on the planning commission, reported that the single largest discussion in connection with A2D2 zoning was absolute height limits on South University. He said that “not a nuance was left unturned” during the discussion. What he emphasized was that there was a trade-off between the higher absolute height limits, the setback, and the maximum tower diagonals.

The complex interplay between various standards was a theme vistited by many councilmembers. On the subject of absolute height limits, councilmember Carsten Hohnke noted that “FARs alone aren’t enough to keep us from being surprised” – an allusion to FAR requirements being in place but still allowing the 601 S. Forest project. So Hohnke raised the issue of the interplay between FAR and massing standards.

Massing standards have to do with the streetwall height, the size of the offset at the top of the streetwall, maximum tower diagonals, and setbacks. This is one of the ways the character districts are more than just colored regions drawn on a map: There are different massing standards for each character district.

Design Guidelines: Character districts, with their different massing standards, reflect some of the work of the design guideline review committee. What has been incorporated into the current zoning revisions are the quantifiable aspects of that committee.

It’s a frequent point of criticism (from Ray Detter, chair of the Downtown Citizens Advisory Council) that the aesthetic parts of the design guidelines have been separated out from the revisions to the zoning currently being considered. At Monday’s working session, Hieftje led off all comments with a question for councilmember Marcia Higgins (who serves on the A2D2 oversight committee along with Evan Pratt of the planning commission, and Roger Hewitt of the DDA board) about when the design guidelines could be expected. Higgins said they’d been put on the back burner, but that late summer or early fall would be reasonable.

Hieftje then elicited from Higgins an assurance that as far as she knew there were no conflicts involved in proceeding with the zoning ordinance revisions without the design guidelines in place.

Other Concerns: This report of council’s discussion of  South University, absolute building heights and design guidelines is not meant to be exhaustive of all topics addressed by councilmembers at their work session. Some of their additional questions overlap with issues raised in the feedback to Rampson’s fall workshop tour. And planning commission’s memo to council provides some explanations about why certain elements of the September 2008 draft were left in place and why certain elements were changed. For this reason, we publish the largest chunk of that memo here.

PC Memo: What Was Left Intact After  Studying Feedback

The memo from planning commission begins with a section on aspects of the proposed zoning that it left intact from its September 2008 draft.

1) Height Limits & Diagonals: The intent behind the proposed Diagonal requirements in most of the downtown core is to balance building “bulk.” Since the Floor Area Ratio (FAR) is fixed once applicable premiums are identified, new projects can either 1) cover most of the site with a lower height or 2) cover less of the site with a higher height. The Calthorpe Report recommends that buildings be allowed to exceed a height limit if certain community goals are provided. Diagonal limits were a recommendation of the Design Guidelines Advisory Committee as the most effective means of allowing a variety of building shapes without resulting in massing that is viewed negatively. Diagonal limits are most effective when there is no height limit, encouraging towers to be more slender with more light and air between buildings. A height limit without any Diagonal requirement will encourage the assembly of parcels and will result in a less desirable continuous building mass covering several sites or entire blocks. Any height limit coupled with Diagonal requirements needs to be considered very carefully because they work counter to each other and could result in requirements that are too restrictive.

Many sites in the proposed interface area (D2) currently have no height limit but would now be limited to a maximum of 60 feet in height. CPC continues to support “no height limit” in most of the D1 district coupled with Diagonal requirements, except for the South University Character Area. (Height in the South University Character Area is addressed further below.) CPC continues to support a 60 foot height limit in the D2 district.

2) Design Guidelines: Any of the recommendations of the Design Advisory Committee that could be stated in ordinance language (numerically quantifiable) are included in the proposed Massing Standards. The remaining recommendations are in the proposed Design Guidelines and will not be referenced in the new ordinance until Council approves them. At the request of the Steering Committee, the approval of the Design Guidelines was set aside to allow the new Zoning Ordinance and Downtown Plan to move toward enactment more quickly. The Design Guidelines were the product of a collaborative and far-reaching effort among the public, staff, and design professionals in response to repeated feedback to promote higher design quality in our built environment. These are recommended in the Calthorpe Report and Council has passed two (2) resolutions supporting the design review process for downtown projects – one asking the Design Advisory Committee to develop Design Guidelines and the other to move them forward with the drafting of ordinance language.

CPC believes the Design Guidelines give more definition to the community’s vision for downtown than is possible in our Zoning Ordinance or our Downtown Plan while allowing design flexibility and creativity. The Design Guidelines are on the CPC Work Plan for recommended approval in June 2009, followed by Council approval. This schedule was preliminary and may need to be adjusted to allow adequate time for its review. CPC requests direction and a desired schedule to assist in meeting Council’s expectations.

3) Flood plain: Construction on many properties within our flood plains throughout the City is currently regulated by the State. The City is in the process of drafting a local Flood Plain Ordinance as an overlay district for all flood plains (not just the Allen Creek) within the city, to be approved along with the new FEMA flood maps. Only a small percentage of our floodplains are within the downtown zoning districts. The concerns raised in this process regarding the Allen Creek flood plain are important but should be addressed in the new Flood Plain Ordinance. However, the Premiums (increased floor area percentage) in the new downtown zoning are not applicable to properties in flood plains.

CPC recommends that all flood plain regulations be incorporated in the new Flood Plain Ordinance and not in the downtown zoning. CPC will be seeking Council input on the proposed flood plain policies before the ordinance is finalized. This is on the CPC’s Work Plan for recommended approval in July 2009, followed by Council approval.

4) Density: The FAR in the downtown core area (D1) as proposed will be increased from 660% to 700% if premium amenities are provided – an increase of about 6%. An additional 200% super-premium is proposed to encourage on-site affordable housing – a community goal that has been difficult to achieve. In the downtown interface area (D2), the FAR as proposed will be 400% maximum if premium amenities are provided – a reduction for many properties. Premium floor area is not applicable to properties within historic districts or flood plains.

CPC continues to support the FAR recommendations. These levels meet the broad goals identified in the Calthorpe Report and the recommendations of the Zoning Advisory Committee.

5) Green space/open space: The Parks, Recreation & Open Space (PROS) Plan recommends that a method be identified to quantify urban open space, green or hard-scaped, to assist the City in evaluating the real need within downtown. The Calthorpe Report addresses Public Space and recommends the careful consideration of edge uses for vitality and safety. The Zoning Advisory Committee was not comfortable encouraging arbitrary locations for open space through the use of a Premium. The proposed ordinance does provide a Premium for Inner Arcades (connecting streets and adjacent sites) and Plazas (open to the sky) on private property, both of which are in our current ordinance. Currently, the new Police/Courts project, the Library Lane underground parking project and the requirement for the 415 W. Washington proposals all include public open space. In concept, CPC believes that large green spaces in the downtown core are counter to numerous goals and that pocket parks are more effective. CPC does not recommend green space or open space requirements as a part of private development in the downtown districts beyond the front open space required on Front Yard Streets at this time. This should be re-evaluated once the Parks Advisory Commission identifies a method of quantifying urban open space.

The concept for the Allen Creek Greenway is supported in the current PROS Plan, the current Non-Motorized Transportation Plan and the new Downtown Plan. Because the majority of the Allen Creek flood plain extends beyond the downtown, CPC does not support using the downtown district zoning to direct its planning.

6) Active Use: The new zoning requirements identify what we would like rather than what exists. Because of this, some non-conforming uses will exist but in time we will make progress toward our goals. The Calthorpe Report recommended that first floor retail not be required everywhere, but maintained in strong areas and encouraged in existing weak retail areas, such as Liberty and Washington between Main and State. The Zoning Advisory Committee recommended requiring first floor retail on certain streets, but did not feel qualified to decide on the streets.

With all this input, the CPC continues to support the 60% minimum frontage of first floor retail on identified “active use” streets to reinforce independent local retailers that depend on pedestrian traffic between adjacent uses for their survival. This includes the main retail sections of Main Street, State Street, Liberty Street, Washington Street and South University. Existing non-conforming uses can continue (see Chapter 55, 5:86).

7) North side of East Huron (Division to State): This block has been a challenge due to the fact that these properties abut residential districts to the north and are in a section of Huron where height was identified in the Calthorpe Report. In an effort to create new zoning that defines our goals, rather than perpetuating what has already been built, the Zoning Advisory Committee struggled, but ultimately recommended that this block be zoned D2 – one major reason was the shading potential of the FAR allowed in the D1 district.

CPC continues to support the compromise of maintaining the D1 district on this block with the additional tower setback from the adjacent residential districts.

8) Downtown Plan: CPC adopted The Downtown Plan on February 19th and has recommended Council adoption.

9) Massing Standards, Character Areas: The eight (8) Downtown Character Areas were identified by the Design Guidelines Advisory Committee with substantial public input. They are based on the unique building and site characteristics within each area.

CPC continues to support the eight (8) Character Areas and the inclusion in the zoning ordinance of the design Massing Standards.

10) Simplify the code: Most downtown projects in the last several years have been reviewed as Planned Unit Developments (PUD) or Planned Projects because of the inappropriateness of our current downtown zoning. The City has encouraged this in order to get projects that more closely align with our Downtown Plan. The uncertainty inherent in both PUDs and Planned Projects have added great expense and additional review time beyond that of a project designed to meet its underlying zoning district. Our current ordinance is actually too simple because it does not adequately define our goals and vision and the current downtown zoning district boundaries are random and without planning logic. The proposed ordinance also includes a vast majority of the recommendations in the new Downtown Plan.

CPC believes that the proposed zoning district boundaries are far more consistent and logical. CPC also believes the proposed ordinance amendments are clear and the new technology tools will make navigation much easier for developers and citizens.

PC Memo: Changes To Proposal After  Studying Feedback

The memo continues by addressing aspects of the zoning recommendation that have changed since September 2008.

11) Premiums: The proposed Premiums generally align with the recommendations of the Calthorpe Report and the more detailed conclusions of the Zoning Advisory Committee. The intent with the Premiums is to get identified public benefits in exchange for allowing additional floor area (up to a maximum). The Residential Premium was reduced from the current ordinance based on a desire to balance the use of all the premiums. With the recent popularity of residential projects it is important to make sure the community also gets the benefits of the other premiums. The use of the Premiums will ultimately be decided through a developer’s financial analysis considering the economic climate at that time.

As this is a moving target, the incentives (increase in floor area percentage) will need to be evaluated on a regular basis to access how they are being used and if the percentages need to be adjusted to encourage benefits that are not otherwise provided.

A Premium for transfer-of-development-rights has not been included. CPC recommends that this be reconsidered for inclusion in the future (currently under more detailed review) as a tool that could be used to protect some historic buildings or could encourage dedicated open space, such as in the Allen Creek floodplain.

CPC has changed the Plaza premium to no longer require these to be located on a street corner. Successful plazas are difficult to design and CPC hopes the added flexibility will provide opportunities where there are adjacent vibrant uses. This was an allowable premium in our current ordinance that was never used but was retained with minor changes to encourage open space on private property.

12) Buffers & Setbacks adjacent to residential districts: Throughout the City, all non-residential districts must currently provide an additional building setback along property lines immediately adjacent to residential districts and matching the setbacks required in that residential district. The proposed downtown zoning also includes additional building setbacks along property lines adjacent to residential districts. These setbacks are part of the Massing Standards for each of the eight (8) Character Areas. They respond directly to the nature of that area and its adjacent residential districts. By their very nature, zoning districts are defined by boundaries and there will always be some level of tension at the dividing line. Neighborhoods’ use and character are protected when they are appropriately zoned and when their boundaries are respected and predictable.

CPC continues to support the proposed building setbacks along adjacent residential districts in all the Character Areas except for South University. The depth of these setbacks is reasonable for the traditional and typical small size of downtown sites. Larger setbacks would encourage the assembly of lots and could make some sites very difficult to build on.

After extensive discussion, CPC has changed the building setback requirement in the South University Character Area to a total of 30 feet along property lines adjacent to residential districts regardless of building height, instead of a 15 foot setback for the first 30 feet in building height and a 30 foot setback for the rest of the building above 30 feet in height. In this area, CPC feels the setback of the lower floors has just as much impact on the neighboring residents as the upper floors.

13) South University character area: CPC support for the 2003 rezoning of this area to C2A was based on its immediate adjacency to the Central Campus. About 50% of the perimeter of this area is bounded by University property, primarily to the north and east, where floor area and height are not regulated by the City. The residents of this zoning district are considered to be primarily students with some University staff – who are the most likely to use walking or biking as their primary transportation thus adding minimally to the motorized traffic and parking in the area. It was also considered a benefit to students and University staff to have the opportunity to live close to their classes or work. The retail in this district, primarily small independent businesses, have been struggling for many years. Some reasons include 1) the distance non-students are willing to walk to shop and dine has diminished as regional opportunities for these have increased, and 2) the student population moving through the district fluctuates dramatically. Finally, the area merchants believe strongly that the captive audience provided by a significant increase in residential density will greatly increase their chances of success. The Calthorpe Report, written just prior to this rezoning, supports this view and states that “local-serving retail districts should first and foremost be located near residential concentrations.”

After extensive discussion, CPC recommends that the South University character area have a height limit of 170 feet to give added design flexibility and increase the opportunity for more light and air between buildings. The recent compromise on the project proposed at 601 Forest would meet this requirement. At this height, CPC also recommends a maximum diagonal requirement of 200 feet [Editor's note: We believe this is a typographical error, and should read "150 feet," which is consistent with the accompanying zoning code revisions forwarded to council  as well as with The Chronicle's previous reporting.] The height limit would not allow an upper tower, so only one diagonal is needed. (The building setback adjacent to residential districts was also modified as described above.)

14) Downtown district boundaries: In order to focus this effort on the zoning requirements rather than district boundaries, the Calthorpe Report included only the non-residential districts directly contiguous to the downtown area, excluding any residential districts. The DDA boundaries are similar but somewhat arbitrary due to the complex political process with other public entities required to change them.

After looking closely at these boundaries, CPC has excluded non-residential properties in the Old Fourth Ward and the Old Westside historic districts from rezoning due to the residential character (and primarily residential use) of these historic districts and the fact that they were created after, and in reaction to, their current zoning designations.

After the new zoning requirements and the design guidelines are in place, and in conjunction with a review of the Central Area Plan, would be an optimal time to re-evaluate the outer boundaries (with possible expansion or contraction) of the downtown districts, including the non-residential and R4C districts.

15) Parking: It is a recommendation of the Nelson/Nygaard downtown parking study that shared public parking be encouraged on appropriate private sites. Any above grade parking that is required parking or public parking on private property up to 200% in not included in a project’s FAR.

CPC has added that any premium for public parking on private property meet DDA standards. Additionally, CPC has clarified that required residential bike parking must be enclosed and lockable.

16) Non-Conformities: The desire to change our current downtown zoning is a reaction to projects that have already been built and a desire to encourage particular types of development. At the same time, it should not be the intent of this ordinance to put an additional burden on buildings that were built under an earlier code – either to require unreasonable changes to existing buildings or to require variances for existing buildings to remain.

CPC has changed the new massing standards to only apply to new buildings or additions.