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Feasibility Report Northeast Lino Lakes Drainage Improvement Project WSB Project No. 02029-790 Page 5 3.3. Receiving Waters Peltier Lake has been listed as an impaired waterbody within the greater Anoka Chain of Lakes since 2002 for aquatic recreation, with the main pollutant identified as excess phosphorus from watershed runoff and internal loading (Minnesota Pollution Control Agency 2013). In addition, the Anoka Chain of Lakes has limited flood storage capacity. Any improvements to the drainage system will need to show no adverse impacts to receiving waters in terms of increased phosphorus loading or flooding potential. 3.4. Existing Site Limitations Anoka County Ditch (ACD) 55 and ACD 72 drain tiles were designed to provide drainage for agricultural lands and are already at capacity, limited by the crossings under I-35E. ACD 55 and ACD 72 both cross under I-35E, as shown in Appendix A, Figure 2, with a total capacity of 1.5 cubic feet per second (cfs) and 0.52 cfs, respectively (RCWD 2014). The City of Hugo contributes 210 acres of the 1,400 total acres and has an existing flow rate of 50.3 cfs into the City of Lino Lakes and the ACD 55 drain tile system. The City of Centerville contributes a minor amount of surface runoff to the study area, which under existing conditions contributes directly to Peltier Lake. The existing agricultural drainage system has been subject to repeated blow-outs and tile ruptures in recent years. In 2014, the Rice Creek Watershed District reviewed the ACD 55 and 72 systems and determined the failures were recurring due to:  Deterioration of the drain tile system, including sections of pipe that have pulled apart, as well as portions of the system have collapsed or are clogged with sediment.  The drain tiles themselves are undersized and unable to convey the incoming flows, resulting in a surcharged system. During the summer of 2015, RCWD maintained several sections of ACD 55 main trunk and the ACD 72 main trunk, as well as several lateral branches. The drain tile system does not provide any water quality benefits to Peltier Lake and field inlets to the system do not have adequate buffers to prevent sediments from entering the system and Peltier Lake. The constraints of the drain tile system have limited landowners’ ability to develop their land consistent with the City of Lino Lakes’ Comprehensive Plan. Development must meet RCWD Rule C for Stormwater Management Plans, which includes water quality and rate control. Because the existing drainage system is already at capacity, any new development must treat their stormwater onsite to meet the water quality, rate control and volume reduction requirements of Rule C. Unfortunately the soils underlying the majority of the study area are poorly suited for infiltration and cannot meet the volume reduction requirements. This has resulted in temporary infrastructure being built because there was not a feasible way to meet the RCWD rules for surface water quality and storage.