Since January of this year, the Kenton County Planning Commission has been hosting all of the major stakeholders in the community that will be affected by the proposed changes to the Kenton County Subdivision Regulations. These face-to-face meetings have taken place so commissioners can hear each group’s comments and concerns. A total of six groups have made presentations to the planning commission, the last of which occurred at the end of April.
It appears that most of the expressed concerns can be addressed. However, there is one main issue that remains unresolved; the issue of how streets should be designed.
“It seems most everyone agrees that some streets are failing before their expected design life,” said Scott Hiles, Deputy Director for Infrastructure Engineering. “But little consensus between the groups has been reached as to the cause of this premature failure, or what should be done about it.”
Staff heard from the majority of local officials that they were spending taxpayer dollars to repair streets long before they should. The early consensus from staff was that water infiltrating under the streets from behind the curb line was one likely culprit. “Most front yards are graded to drain toward the street,” said Hiles. “During much of the year water from sump pumps, gutters, overwatering of irrigation systems and just rainfall can flow to the street, get behind the curb and ultimately under the street causing some of these failures that local officials are seeing.”
Staff addressed this issue by proposing an underdrain under the entirety of the curb line for all streets. From that point forward, the Northern Kentucky Homebuilder’s Association Land Development Council (LDC), Northern Kentucky Society of Professional Engineers (NKYSPE) and the Kenton County Mayors’ Group have all weighed in with different proposals.
The LDC’s position has been that the current standards for street design seem to be sufficient, but that individual situations may warrant a design upgrade. The LDC is in support of keeping the street standards as they are, but letting a geotechnical investigation determine if and where an upgrade to the standards should be provided.
“The Northern Kentucky Homebuilder’s Association Land Development Council recognizes that the current pavement regulations are performing well in other municipalities in Northern Kentucky, and that the key to reaching the design life of any pavement is proper well timed care and maintenance during the pavement’s lifecycle,” said Joe Kramer, an engineer representing the LDC. “The proposal to install underdrains and granular drainage blankets under all pavements will not add a significant benefit to the performance and lifecycle costs of the pavement.”
NKSPE did recommend requiring an underdrain under the curb, but only in street sag locations and fronting lots where 95% of the lot drained toward the street. NKSPE also recommended a change to the aggregate used in the concrete for concrete streets.
“Through our research the NKSPE Pavement review committee found that the majority of current pavement failures are the result of inconsistent materials, and therefore most of our recommendations focused on the need for better specifications and monitoring of the materials used,” said Michelle Bollman, President of the NKSPE. “We also identified the need for some subsurface drainage improvements and a better maintenance plan in our recommendations.”
The Mayors’ Group took staff’s proposal one step further. They are recommending that in addition to the underdrain under the curb, a drainage blanket under the pavement also be required to capture any additional water that may be either present in the subgrade soils or infiltrate through the pavement itself. “As local officials, our goal was to propose a street design that will stand the test of time so that city and county taxpayers aren’t required to pay to fix streets that fail prematurely,” said Crestview Hills Mayor Paul Meier, Chairman of the Kenton County Mayors’ Group. “We’re confident that our proposal accomplishes this goal.”
The planning commission recently requested that each group provide cost information for the proposals and are expecting to receive that information soon. “Cost will ultimately be one of the primary factors the planning commission has to consider when they choose which proposal to adopt,” said Paul Darpel, Chairman of the Kenton County Planning Commission.
But rather than just basing their decision on what the cost increase would be for an upgraded street standard, they’ll have the difficult job of weighing the increased cost against the benefit the overall community would receive. That decision will be made by the planning commission later this year at a special public hearing which has yet to be scheduled.