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TOWN OF MORRISVILLE
6-28
To ensure the continued function of stormwater BMPs, Section 7.4 of the UDO specifies
performance securities for stormwater BMPs. An installation performance security deposit
is required, equal to the total estimated construction cost, plus 50 percent. A maintenance
performance security is also required, equal to 30 percent of the total estimated construction
cost.
The Town recently developed and adopted a new Engineering, Design, and Construction
Manual (EDCM) containing updated stormwater quantity and quality measures. The
EDCM also provides clarifications of the BMP manual.
6.2.5
Stormwater Programs
The Town is only 9.8 square miles and is surrounded by the airport, RTP, and the Town of
Cary, so it has limited potential to expand beyond its current ETJ. Given the proximity of
the Town to employment opportunities in RTP and access to the airport, the Town has
planned for higher-density development in much of its Planning Area. The Town has
developed a stormwater management program to control the rate of stormwater runoff
from high-density areas. The Town’s stormwater program is administered by its
Engineering Department. The staff is charged with upholding the local, State, and Federal
regulations related to stormwater. These legal requirements include:
Floodplain Management
WSW Protection
NPDES Phase II Stormwater Regulations
Neuse River Basin Buffer Rules
Jordan Lake Buffer & Stormwater Rules
The Town has assumed responsibility for administering the BMP program for quality from
NCDENR. On February 28, 2012, the Town Council approved a stormwater funding
resolution that gave the ability to establish a stormwater utility fee for developed property
containing impervious surface within the Town. The fees collected will assist in the costs
involved in administering the stormwater program.
6.2.5.1
Stormwater Regulations
In January 2012, the Town adopted a new Stormwater Management Ordinance, which
substantially expanded the Town’s stormwater management efforts. This ordinance is
summarized in Article 7 of the Town’s UDO. The ordinance establishes minimum
requirements and procedures to control the adverse effects of stormwater runoff associated
with increased development. The ordinance also prohibits any person from developing land
without having proper stormwater control measures in place. The ordinance effectively
implements the Jordan Lake rules for new development throughout the entire Town. The
minimum requirements of the ordinance include that developers must also meet all other
State and federal rules. Stormwater BMPs must be implemented to control and treat the
runoff volume generated from 1.5 inches of rainfall. In addition, pre- and post-development
peak runoff rates must be equivalent for the 1-year, 24-hour; 2-year, 24-hour; and 10-year,
24-hour storms.