AGENDA #9

MEMORANDUM

 

TO:                  Mayor and Town Council

 

FROM:            W. Calvin Horton, Town Manager

 

SUBJECT:       Town Operations Center Initial Planning Guidance

 

DATE:             March 3, 2003

 

 

This memorandum reviews the initial planning work completed to date on the Town Operations Center.  The following resolution would authorize the Town Manager to pursue development of a conceptual plan consistent with on of the two design schemes developed by the consultants working with Town staff.

 

BACKGROUND

 

The Public Works and Transportation Departments are located on the Horace Williams Tract, on land leased from the University of North Carolina.  The term of the lease expires on December 31, 2006, and the University has declined to extend it.

 

The Council has purchased land for a new site on Millhouse Road, north of Eubanks Road, between I-40 and the railroad.  On December 13, the Council authorized a contract with a consultant team led by Corley Redfoot Zack to prepare a site analysis, needs assessment, conceptual site plan and preliminary cost projections for the new operations center. 

 

The contract included a compressed schedule that would allow the Council to make a final decision on cost by August 25.  This date would be the last meeting at which the Council would have the option of deciding to hold a bond referendum in November, if General Obligation Bonds are chosen as a means to finance part of the project.  The cost figures resulting from this design contract would also be essential to an effective campaign to acquire federal funding of up to 80% and state funding of up to 10% of the costs related to the transit operations.  (Please see Attachment #1, the project schedule.)

 

Since mid-December the site analysis has been completed, although refinements to it will continue.  The consultants have analyzed questionnaires completed by almost every employee in the Public Works, Transportation, Engineering and Housing Departments, interviewed many employees on-site, prepared a book of draft design criteria and reviewed staff comments on that first draft.

 

Based on the information described above, and after four full days spent on-site interacting with employees, the consultants developed two design schemes.  These represent two different approaches to the design challenge of accommodating the operational needs of the Town on this site while honoring the goals of sustainable development, environmental sensitivity and fiscal prudence.

 

The design schemes should not be mistaken for plans.  They are more preliminary even than conceptual plans.  They are diagrams which suggest a design approach.  As the design is refined in an iterative process, problems will be identified and resolved until a concept plan has been developed.

 

DISCUSSION

 

Site Analysis

Prior to a comparison of the two design schemes we review below the site analysis information generated by the consultants and considered in their preliminary design process.

 

Existing Site Zoning:

The creek that runs through the middle of the property is also the jurisdictional boundary between the northern 31.9 acres in Orange County’s planning jurisdiction and the southern 43.7 acres in the Town’s planning jurisdiction.  Considering the Resource Conservation District overlay in the Town’s jurisdiction the site includes the following three zoning districts:

 

            Chapel Hill Mixed Use Residential-1 (MU-R-1)                        31.1 acres

            Chapel Hill MU-R-1 in Resource Conservation District 12.6 acres

            Orange County Rural Buffer (RB)                                             31.9 acres

           

            Total Site                                                                                  75.6 acres

 

 In the Chapel Hill MU-R-1 district, development of a “Public Use Facility” is a permitted use requiring approval of a Special Use Permit if more than 40,000 square feet of land disturbance is proposed.  In the Resource Conservation District, development is restricted. 

 

In the Orange County Rural Buffer district, development of a “Government Facility or Office Building” is a permitted use, but the approval process is not under the purview of the Town Council. It is also possible that an amendment would be needed to the Joint Planning Land Use Plan; such an amendment would need to be approved by Orange County and the Towns of Carrboro and Chapel Hill.  If no buildings are proposed in this area, however, we understand that other development could take place and that it would not require a permit.

 

Site Context Issues:

I-40 borders the site on the east and this proximity results in relatively high ambient noise levels over much of the site.  The railroad tracks on the west side separate the site from seven residential properties along Millhouse Road.   To the south and southwest there are two adjacent residential properties on 10+ acre lots.

 

Existing Vegetation:

The site is a mix of open and wooded areas including a large central field, several areas dominated by young pine trees and stands of mature hardwoods around the three streams that cross the property.  In addition, two other stands of significant trees are noteworthy, including a concentration of large hardwoods on the slope north of the existing pond and a large area of mature hardwoods south and east of the site’s central field.  A small area above the pond, where no site disturbance is anticipated, meets the Army Corp of Engineers wetlands definition.

 

Existing Soil and Subsoil Conditions:

In general, the soils on all of the upland sections of the site are suitable for development with most of the MU-R-1 zoning district being in the “Greenville” soil series, which is particularly good for urban type uses.  Although a complete analysis of recent subsurface borings is still being completed, preliminary information indicates that subsurface conditions, are not anticipated to constrain development on sections of the site outside of the Resource Conservation Districts.

 

Existing Topography:

With the exception of limited areas within the Resource Conservation Districts, essentially the entire site includes slopes less than 10% with the large majority of this area with slopes less than 5%. 

 

Anticipated Buffers and Buildable Areas:

The buffers anticipated for the development include the required 100’ wide buffer along I-40 and proposed 50’ wide buffers along other property lines in areas where either a 20’ or 30’ minimum width would be required by the Town’s regulations.  Considering these anticipated buffers along with stream setback requirements consistent with the Town’s Resource Conservation District regulations, two “buildable envelopes” can be quantified.  These envelopes include approximately 20.2 acres in the Orange County’s Rural Buffer zoning district and approximately 25.1 acres in Chapel Hill’s MU-R-1 zoning district.

 

Drainage Patterns:

In general, natural surface drainage flows to the site’s three streams which then cross under I-40 in existing culverts.  Sheet flow on to the site from surrounding properties is essentially non-existent due to grading associated with the railroad tracks along the western property line. Sheet flow off of the site to adjacent properties is limited to a small section of the central field adjacent to the southwest property line.  Three low areas exist on the site outside of the Resource Conservation Districts that are suitable locations for stormwater quality ponds.

 

Existing Municipal Operations Facility:

For purposes of comparison, the Town’s leasehold on the Horace Williams Property includes 24.2 acres. This site is approximately 70% impervious surface, and includes no surface stormwater improvements.

 

Description of Design Schemes

During the intensive design workshop of February 18 – 21, 2003, the design consultants initially developed six alternative conceptual design schemes for review by the Town staff’s project review committee.  These schemes included two basic approaches, either with or without proposed enclosed structures on the northern section of the property.  Two of the six schemes were then selected by the consultants and staff committee for further refinement to illustrate the development potential of the two basic design approaches. 

 

The option identified as “Scheme 3” sites all enclosed structures on the southern section of the site, with only bulk outdoor storage and the Police Department vehicle impound lot in the north.   “Scheme 4A” locates the Transportation Department on the northern section of the site and the Public Works, Engineering and Housing Departments on the southern portion.

 

Each design scheme includes the square footage of buildings, parking and outdoor storage spaces projected to be needed in 2036. At this schematic stage, however, the dimensions of areas associated with non-programmed uses, such as site landscaping, are not fully quantified and may affect how each scheme could meet the specific long term operational needs.

 

Each scheme is a preliminary diagrammatic representation of a design idea.  The rectangular shapes represent two-dimensional space, not the footprint or height of buildings.  Everything is expected to change as design work becomes refined.  Therefore, the observations and comparisons we make below are necessarily general.

 

Notwithstanding the paragraph above, we believe that it would be useful to evaluate the two general approaches now.  It appears that each could be developed into an operational site, meeting the space needs that we project for the next 30 years.  However, we believe that there are trade-offs to be made in choosing between the two approaches. Guidance from the Council at this point in the design process would be most useful in focusing the work that will lead to a conceptual plan for review in April.

 

From the beginning of this project, in addition to meeting operational requirements, emphasis has been placed on three primary design criteria: Sustainable Design, Environmental Sensitivity and Fiscal Prudence.  Following a brief description of each of the two schemes are lists, based on these three primary design criteria, that highlight the most significant issues of each scheme.  While both schemes include buildings sited to maximize daylighting opportunities, most other issues of sustainable development, such as water reuse, recycling and energy efficient structures can not be evaluated at this early stage of planning.

 

In addition to the primary design criteria, there are issues related to permitting and planning that merit consideration when comparing the schemes and determining how the Town should proceed with more detailed design work.  These issues are discussed separately at the end of this section of the report.

 

Scheme 3: The Southern Option

 

This scheme concentrates all enclosed structures within Chapel Hill’s MU-R-1 zoning district and locates all building functions, with the exception of Transit Administration and Operations, centrally on this section of the site in what is shown diagrammatically as a single large building.  A smaller Transit Administration and Operations building is sited adjacent to the bus storage area.  Between these buildings is a two story parking facility sized to accommodate the vehicles of up to 440 employees and visitors.  Primary buildings are oriented from east to west to take advantage of solar technology and daylighting opportunities.

 

Operational Issues:

• Larger undeveloped section within Rural Buffer would remain available for possible future municipal uses
• Compact design would permit efficient shared use of joint facilities (e.g., training room)
• Buildings would screen operations area from adjacent property to the south
• Site circulation would likely include closely spaced intersections near the project entrance that would need to be carefully designed to avoid traffic conflicts
• Circulation space around salt and sand storage structures, while adequate, might reduce efficiency and safety of winter storm response and could be disruptive to other operations
• Office and other employee and public use spaces would likely be surrounded by functional areas and have little visual connection to the site’s significant preserved natural areas
• Limited passive recreation opportunities would be available adjacent to employee work and break areas
• Use of essentially all buildable area within the MU-R-1 zoning district would reduce flexibility for functionally designed incremental expansions beyond the 30-year needs projected. Anticipated necessary subsurface storm water management structures would require more extensive ongoing maintenance than surface drainage systems

 

Sustainable Design and Environmental Sensitivity:

 

• Would preserve larger undisturbed area within the Rural Buffer
• Use of structured parking would reduce total impervious surface
• Extensive grading would be inconsistent with the site’s natural hydrology and would  prevent inclusion of a stormwater quality pond in the center part of the site
• Anticipated underground stormwater volume control structures would be less effective at stormwater quality mediation than surface features sized to accommodate similar volumes
• Removal of the large area of notable specimen hardwood trees would be necessary to accommodate Transportation Department service facilities
• Programmed use of essentially the entire buildable area in the MU-R-1 zoning district would limit possible use of grassed swales, bio-retention areas and landscape areas available for permanent internal tree planting

 

Fiscal Prudence:

 

• Shorter utility routing would allow for modest reduction in utility installation costs
• Probable large building footprint and continuous surrounding paved areas would require extensive use of retaining walls resulting in higher costs
• Two-story parking structure would increase cost of employee and visitor parking
• Anticipated subsurface stormwater management structures would be significantly more costly than surface improvements

 

Scheme 4A: The Northern and Southern Option

 

This scheme includes construction of enclosed structures within Orange County’s Rural Buffer zoning district and divides the development’s programmed needs into two zones on either side of the central pond and RCD.  The Town’s Transportation Department facility would be located to the north of this RCD and a combined Public Works, Engineering and Housing Maintenance facility would be located to the south.  The scheme encloses two primary structures which could be configured in a variety of ways as the design is refined.  Employee and visitor parking are proposed in surface lots.  Primary buildings are oriented from east to west to take advantage of solar technology and daylighting opportunities. 

 

Operational Issues:

 

• Extension of Millhouse Road entrance would improve interior circulation and reduce traffic conflicts associated with multiple closely spaced intersections
• Location of salt and sand structure would provide safer, more efficient and less disruptive winter storm response
• Office and other employee and public use spaces could be oriented to take advantage of the site’s preserved natural areas and passive recreation areas could be accommodated adjacent to employee break and work areas
• Fewer space restraints would allow a more flexible design that could more readily accommodate functionally designed incremental expansion and/or change
• Less compact design may result in less efficient shared use of some joint facilities (e.g., training room)
• Smaller undeveloped section within the Rural Buffer would remain available for possible future municipal uses
• Public Works operations area would not be screened from the adjacent property to the south by buildings

 

Sustainable Design and Environmental Sensitivity:

 

• Use of natural hydrology could accommodate recommended central stormwater quality pond
• Less extensive continuous grading and less soil relocation by cut and fill would increase effectiveness of soil erosion control measures
• Primary use of surface stormwater features to control run-off rate and volume would be more effective than other measures at improving stormwater quality
• Large area of mature specimen hardwoods could be preserved between the proposed Public Works facility and the material storage area
• Design flexibility inherent in less compact plan would provide opportunities for bio-retention and interior site tree planting and landscape improvements
• Would preserve smaller undisturbed area within the Rural Buffer
• Total impervious surface would increase if surface parking is utilized for employees and visitors

 

Fiscal Prudence:

 

• Significantly less overall grading and fewer retaining walls would reduce site preparation costs
• Opportunity to use surface parking rather than a parking deck would reduce cost of employee and visitor parking
• Opportunity to rely almost exclusively on surface stormwater drainage improvements would reduce cost of meeting Town stormwater regulations
• Longer utility routing would marginally increase utility installation costs

 

Permitting and Planning Issues:

 

The permitting process necessary to construct the new Town Operations Center would be different for the two conceptual design scheme options described above.  The following summarizes some significant issues that might arise during the permitting process for each of the two schemes:

 

SCHEME 3: The Southern Option

Because no covered structures or utility extensions are being proposed in the Rural Buffer we believe that no permits other than Council approval would be required for improvements in this area.  This is based on North Carolina State statutes that exempt the State and its subdivisions from local zoning regulations for property improvements that do not include the construction of buildings.

 

Within the Town’s MU-R-1 zoning district, the proposed project is a permitted use, and its size requires that it obtain a Special Use Permit.  Issues that may be challenging to address include the following:

 

Stormwater Management:

Because the development program necessitates large buildings and large vehicle storage areas, opportunities for surface stormwater management features would be limited.  Although it may be possible to meet required quantitative regulations using large underground stormwater structures, the Land Use Management Ordinance’s qualitative standards of using the natural hydrology of a site to guide design would not likely be fully realized.

 

Tree Protection:

The density of development would affect our ability to address the Town’s stated goal of preserving rare and specimen trees on development sites whenever possible.  The anticipated need to utilize essentially all of the buildable area within the MU-R-1 zoning district for constructed improvements will likely preclude opportunities for existing vegetation to be retained in this area. 

 

SCHEME 4A: The Northern and Southern Option

Scheme 4A would require that Orange County and the Town of Carrboro be involved in the permitting process and, although it may meet both the intent and the spirit of the Town’s Land Use Management Ordinance, this involvement by other jurisdictions would affect the timeliness of the approval process and our ability to complete work on schedule. 

 

As mentioned in the Site Analysis Summary, a “Government Facility and Office Building” is a permitted use in the Rural Buffer zoning district.  However, we understand that some of the accessory uses would require that the Board of County Commissioners to approve a Special Use Permit.  The issuance of any permit by Orange County in that area would also require a 45-day period for courtesy review by both Towns.

 

CONCLUSIONS

 

We believe that both design schemes could accommodate the Town Operations Center through at least 2036. Many potential difficulties mentioned above could probably be addressed during subsequent design work which will determine more definitively how the Town’s operations needs could be addressed while meeting the Town’s regulatory requirements.  However, we believe that there are basic differences that would remain.  We request the Council’s guidance on which design approach to pursue as the consultants refine their design work to reach the level of a conceptual plan that can be discussed in April.

 

Scheme 4A, the Northern and Southern Option, provides more room for expansion and/or changes, for traffic circulation, for retention of specimen trees and for green space close to working areas and break rooms.  This scheme would allow a more natural stormwater management system, including a central pond. 

 

However, Scheme 4A could not be built without amending the Water and Sewer Boundary Agreement and, possibly the Joint Planning Agreement.  Even if all parties were in agreement, such amendments would require several months at best and would not allow a decision on costs to be made by the end of August.

 

Scheme 3, the Southern Option, minimizes the amount of impervious surface and maximizes the amount of untouched land.  It provides a more urban environment than 4A.  Because of more extensive grading, retaining walls, structured parking and underground stormwater management, it would be more expensive than Scheme 4A.

 

Scheme 3 would leave a large contiguous area in its natural state.  This land would remain as natural habitat for now.  In the future it might be needed for as- yet- undesignated public purposes. If so, it is likely that it would be the only extensive, undeveloped, relatively flat land then available.

 

RECOMMENDATION

 

That the Council adopt Resolution A, authorizing the Manager to pursue a conceptual plan for the Town Operations Center consistent with Scheme 3, the Southern Option.

 

ATTACHMENTS

 

1. Project Schedule (p. 11).
2. Site Plan – Scheme 3 (p. 12).
3. Site Plan - Scheme 4A (p. 13).

 

 

RESOLUTION A

 

A RESOLUTION DIRECTING THAT THE PLANNING OF THE TOWN OPERATIONS CENTER FOCUS ON SCHEME 3, THE SOUTHERN OPTION (2003-03-03/R-6a)

 

WHEREAS, the Town has hired consultants to develop a needs assessment, site analysis, conceptual plan and cost estimate for the Town Operations Center on Millhouse Road; and

 

WHEREAS, the consultants have, working with Town staff, completed the needs assessment and a set of draft design criteria; and

 

WHEREAS, the consultants have, working with Town staff, conducted an intensive 4-day design workshop; and

 

WHEREAS, said design workshop included the development of six design schemes, followed by focus on and refinement of two of these schemes; and

 

WHEREAS, each of the two design schemes has advantages and disadvantages;

 

NOW, THEREFORE,  BE IT RESOLVED by the Council of the Town of Chapel Hill that the Manager is authorized to pursue a conceptual plan for the Town Operations Center consistent with Scheme 3, the Southern Option.

 

This the 3^rd day of March, 2003.

 

RESOLUTION B

 

A RESOLUTION DIRECTING THAT THE PLANNING OF THE TOWN OPERATIONS CENTER FOCUS ON SCHEME 4A, THE NORTHERN AND SOUTHERN OPTION (2003-03-03/R-6b)

 

WHEREAS, the Town has hired consultants to develop a needs assessment, site analysis, conceptual plan and cost estimate for the Town Operations Center on Millhouse Road; and

 

WHEREAS, the consultants have, working with Town staff, completed the needs assessment and a set of draft design criteria; and

 

WHEREAS, the consultants have, working with Town staff, conducted an intensive 4-day design workshop; and

 

WHEREAS, said design workshop included the development of six design schemes, followed by focus on and refinement of two of these schemes; and

 

WHEREAS, each of the two design schemes has advantages and disadvantages,

 

NOW, THEREFORE, BE IT RESOLVED by the Council of the Town of Chapel Hill that the Manager is authorized to pursue a conceptual plan for the Town Operations Center consistent with Scheme 4A, the Northern and Southern Option.

 

This the 3^rd day of March, 2003.