The cost of building a home in southwest Manteca could jump $3,145 on April 20.That’s the date a fee on new residential construction to help fund 200-year flood protection improvements will go into effect should the City Council approve flood control impact fees Tuesday. The council meets at 7 p.m. at the Civic Center, 1001 W. Center St.The council vote comes 20 years after floodwaters from the 1997 levee breaks that inudanted upwards of 70 square miles between Manteca and Tracy. Ten feet of water was still covering homes in the Wetherbee Lake neighborhood at the western end of Woodward Avenue on Feb, 7, 1997.Fees are also being established for commercial, industrial and multi-family developments in the 200-year floodplain that is within the city limits.