(a) The City of York has been divided into release rate areas as shown in Appendix C.
(b) Description of stormwater management districts - two types of stormwater management districts may be applicable to the City of York, namely the Release Rate Districts and Provisional No Detention Districts as described below:
(1) Release Rate Districts - Rate districts differ in the extent to which post-development runoff must be controlled. Within a given district, the post-development peak rate of storm runoff must be controlled to the stated percentage of the pre-development peak rate of storm runoff in order to protect downstream watershed areas.
(2) Provisional No Detention Districts - These watershed areas may discharge post-development peak runoff without detention without adversely affecting the total watershed peak flow. In certain instances, however, the "local" runoff conveyance facilties, which transport runoff from the site to the main channel, may not have adequate capacity to safely transport increased peak flows associated with no detention for a proposed development. In those instances, the developer shall either use a 100% release rate control or provide increased capacity of downstream drainage elements to convey increased peak flows consistent with Section 937.07(d). In determining if adequate capacity exists in the local watershed drainage network, the developer must assume that the entire local watershed is developed per current zoning and that all new development would use the runoff controls specified in this Ordinance. Similarly, any capacity improvements must be designed to convey runoff from development of all areas tributary to the improvements consistent with the capacity criteria specified in Section 937.07(f).
(3) When a project or land disturbance activity is located in more than one stormwater management district, stormwater may not be transferred from a district with stricter stormwater management criteria to a district with less strict criteria, unless the need for such a transfer is identified in the regional water quality management plan Act 167 Study. In any district, infiltration and volume regulations dictated in Section 937.04 will be required.
CODORUS - DISTRICT 1
District ID | Regulated Storm Frequency | Percentage of Pre- Developed Peak Flow Rate to Determine Allowable Post-Developed Release Rate |
District 1 | 2 | 100% 2-Year |
District 1 | 5 | 100% 5-Year |
District 1 | 10 | 100% 10-Year |
District 1 | 25 | 100% 25-Year |
District 1 | 50 | 100% 50-Year |
District 1 | 100 | 100% 100-Year |
* The intention of this Table is to reduce the runoff rate. (Ord. 32-2011. Passed 10-4-11.)