AGENDA #5g
MEMORANDUM
TO: Mayor and Town Council
FROM: W. Calvin Horton, Town Manager
SUBJECT: Response to Referral of Report on Comparison of 2,000 sq.ft. vs. 5,000 sq.ft. Threshold for Stormwater Management and Tree Protection Controls for Single-Family/Two-Family Lots
DATE: May 10, 2004
This report responds to a Council request for further discussion of the 5,000 square foot threshold for stormwater management and tree protection controls for single-family/two-family lots. This report transmits the recommendation of the Planning Board and provides a discussion of the recommendation.
At a Budget Work Session on February 27, the Town Council asked for staff comments on the following topic:
What would be the impacts of changing the threshold for requiring stormwater management and tree protection controls for single-family and two-family lots from the existing threshold of 5,000 square feet of land disturbance, to a new threshold of 2,000 square feet?
On March 30, 2004, the Town Council received a budget working paper that addressed the January 2003 Land Use Management Ordinance provisions regarding stormwater management and tree protection for single-family and two-family development. The 2003 Ordinance established 5,000 square feet in area as the threshold for stormwater management facilities and for tree protection.
During discussion on March 30, the Council asked for information about the number of applications for home construction that might have fallen under the 5,000 square foot threshold. At the conclusion of its consideration, the Council referred the issue to the Planning Board for further discussion. A copy of the Planning Board recommendation is attached.
ORDINANCE PROVISIONS
In January 2003, the Council enacted a Land Use Management Ordinance that contained several new provisions regarding stormwater management and tree protection. Among the new requirements:
Prior to January 2003, no stormwater management or tree protection regulations applied to construction activity for a single-family or two-family dwelling on an individual lot.
As the Town Council considered enacting these new requirements during the spring and fall of 2002, discussion focused on the benefits and costs of the proposed requirements. We recall the following points raised during deliberations:
Benefits of Requirements Costs of Requirements
* Additional control of stormwater runoff * $1,500-$5,000 to homeowner per
application
* Identification of rare and specimen trees * 5-15 hours of staff time per
application
* Tree protection devices during construction
In the end, the Council determined that a threshold of 5,000 square feet would strike a reasonable balance in achieving public objectives for stormwater management and tree protection while minimizing imposition on private property owners and minimizing the need for additional staff resources. A threshold of 5,000 square feet of disturbed land area means that almost all construction of new single-family or two-family dwellings will need stormwater controls and will need to install tree protection devices during construction; and that most additions to existing dwellings will not have these requirements. (Please see attached memorandum on this topic from the Planning Director.)
The Council determined at that time to set the same threshold of land disturbance for triggering both stormwater and tree protection requirements. This decision was based in part on a recommendation from the Manager that having different thresholds would likely add complexity for citizens and property owners in determining what regulations apply to their property, without significant benefit of differentiated thresholds. We suggested at the time that a common threshold makes for clearer process: over 5,000 square feet of land disturbance, a homeowner will need to hire design professionals to work on an application; under 5,000 square feet of disturbance, professional engineering and landscape architecture expertise would likely not be required.
These requirements have been in place for just over a year. We reported in March that during this approximately 14-month time frame, we processed 506 applications for single-family Zoning Compliance Permits. Following is a breakdown of these 506 applications:
Denied or Returned as Incomplete: 66
Approved, Land Disturbance > 5,000 sq. ft. 155* (50 non-Meadowmont)
Approved, Land Disturbance 2,000-5,000 sq. ft. 53
Approved, Land Disturbance < 2,000 sq. ft. 232
TOTAL 506
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*Of the 155 applications over 5,000 square feet, 105 were in Meadowmont where individual stormwater management and tree protection controls are not required, because stormwater and tree protection are managed development-wide through Special Use Permit requirements.
The bottom line, for the year, is that 50 new single-family/two-family applications came in showing land disturbance greater than 5,000 square feet, and were required to include stormwater management and tree protection controls. Another 53 applications came in showing land disturbance between 2,000 and 5,000 square feet, which were not required to include stormwater and tree protection controls. Accordingly, if the threshold triggering stormwater management and tree protection requirements were to be changed from 5,000 square feet to 2,000 square feet, the number of applications subject to the requirements could be expected to double. The majority of the applications that would be newly made subject to the requirements would be for additions to existing dwellings.
The Council asked, on March 30, for further description of the 53 applications that proposed land disturbance between 2,000 and 5,000 square feet. We offer the following information:
Disturbance between 4,000 and 5,000 square feet: 20 properties
Disturbance between 3,000 and 4,000 square feet: 11 properties
Disturbance between 2,000 and 3,000 square feet: 22 properties
53 properties
All but seven of these applications proposed additions to existing dwellings. Five of the applications were for new construction of size restricted houses at the Parkside Development.
The current threshold of 5,000 square feet of land disturbance to trigger stormwater management and tree protection controls means that almost all applications for construction of new single-family or two-family dwellings must include these controls; and most additions to existing structures do not. Changing the threshold to 2,000 square feet would mean that many additions to existing single-family or two-family structures would need to include these controls. We estimate that the number of such applications for additions affected would be approximately 50 per year, doubling the number of applications that are currently subject to these requirements.
A reasonable projected estimate of staff time required to process applications if this change were made would be approximately 500 hours per year.
The Planning Board recommended that the current 5,000 square foot threshold of land disturbance for stormwater management and tree protection controls for single-family/two-family lots is too high. The Board further recommended that the two thresholds be decoupled, because of the complexity of issues involved in stormwater controls; the Board suggested that thresholds for stormwater controls may be more effective with consideration of topographic conditions as well as consideration of the amount of impervious surface proposed. A copy of the Planning Board’s memorandum discussing these issues is attached.
RECOMMENDATIONS
Planning Board’s Recommendation: The Planning Board recommendation (attached) offers the opinion that the current 5,000 square foot threshold of land disturbance for stormwater management and tree protection controls for single-family/two-family lots is too high. On April 6, 2004, the Planning Board voted 9-1 to recommend that stormwater controls and tree protection be decoupled for this type of development.
Manager’s Recommendation: If the Council wishes to make this change, the next step would be to call a Public Hearing to consider an amendment to the Land Use Management Ordinance to effect the change. We do not recommend adjusting the regulations in a manner that would require that engineering studies be performed on a property before it could be determined what regulations would apply to the expansion of an existing dwelling.
ATTACHMENTS