October 8, 2019
Media Contact:
Mark Miller, Administrator, Office of Public Information, 410-313-2022
Resolutions mandate highest standards ever in Howard County’s history for storm water management
ELLICOTT CITY, MD – The Howard County Council has approved two resolutions proposed by County Executive Calvin Ball that will strengthen development regulations and fees to protect the Tiber Branch and Plumtree Branch watersheds and mitigate flooding in Ellicott City. The first resolution will require development to meet the highest standards ever in Howard County’s history for storm water management, addressing the short duration, high-intensity storms that caused recent, devastating flooding in 2016 and 2018, and establishing a more rigorous process for permitting the use of fees-in-lieu. The second resolution will more than double storm water management fees-in-lieu and bring them up-to-date to reflect current costs for constructing storm water management facilities. These fees have not been increased since the mid-1990’s. Read the full text of Resolution 122-2019 here and Resolution 123-2019 here.
“I thank Council Chair Christiana Mercer Rigby, Council Vice-Chair Opel Jones and Councilmembers Deb Jung and David Yungmann for voting in favor of these resolutions that will help protect our environment and mitigate flooding within the Tiber and Plumtree watersheds,” said Ball. “These resolutions are part of our multi-faceted Ellicott City Safe and Sound Plan. Over the past year, our plan has created a more resilient, prepared, economically vibrant and environmentally sustainable Ellicott City. As we continue to repair from the damage of the 2016 and 2018 floods while preparing for potential upcoming severe weather events, we are committed to protecting Ellicott City through innovative capital projects and from smart and forward-thinking policies such as CR-122 and CR-123. These resolutions will ensure that developers are building the infrastructure necessary to manage the rainfall from increasingly severe weather.”
1) Storm Water Management Requirements (CR123)
The Tiber Branch Watershed and Plumtree Branch Watershed Safety Act (CB56-2018) required storm water management to be analyzed for both watersheds. This resolution implements some of the resulting recommendations, which will require future developments to manage short duration, high intensity storms. The goal is to provide adequate management for stormwater runoff to help mitigate flooding.
The resolution amends Volume I (Storm Drainage) of Howard County’s Design Manual to require the management of a 3.55-hour, 6.6-inch storm (equivalent to the July 30, 2016 storm) in both watersheds, as well as a requirement to address a 10-year, 24-hour (4.9 inch) and 100-year, 24-hour (8.51 inch) storm in the Plumtree Branch watershed. These requirements will extend to all projects in both watersheds, regardless of when a developer received subdivision or site development plan approval.
The goal for storm water management is to reduce peak runoff for development equal to or less than pre-development site conditions, which are modeled as “woods in good condition.” Alternative management strategies are permitted only when geotechnical issues exist that make managing the short duration, high intensity storm impossible on-site. All development must manage the 100-year storm regardless of geotechnical conditions.
2) Storm Water Management Fees-in-lieu (CR122)
This resolution works as a companion to the first by more than doubling the fees-in-lieu to construct stormwater management by from $72,000 to $175,000 per acre foot of water storage.
To determine these new fees, the County conducted case studies of existing storm water management ponds to arrive at a per acre foot cost to store storm water. The fees will only be paid if geotechnical issues exist that make managing the short duration, high intensity storm impossible on-site and there are no opportunities to implement stormwater management off-site within the same watershed. Any funds collected by the Department of Planning and Zoning (DPZ) will go toward flood mitigation efforts in the watershed.