How to edit a Gulp task so that .map files are saved correctly?

Question

Sass

Previously, the config saved .map in the body of the files - now there is a need to store them separately.
Changed the config to this:

// SASS/SCSS
// ===========================================
gulp.task('sass:build', function () {
  return gulp.src(path.build.sass)
    .pipe(sourcemaps.init())
    .pipe(sass().on("error", notify.onError()))
    .pipe(autoprefixer(['last 20 versions', '> 1%', 'ie > 8']))
    .pipe(rename(function (path) {
      path.extname = ".css"
    }))
    .pipe(sourcemaps.write('/maps'))
    .pipe(gulp.dest(path.build.cssPath))
    .pipe(cleanCSS())
    .pipe(sourcemaps.write('/maps'))
    .pipe(rename(function (path) {
      path.extname = ".min.css"
    }))
    .pipe(gulp.dest(path.build.cssPath))
    .pipe(reload({stream: true}));
});

As a result, a maps folder is created in the CSS folder, but in addition to map files, it contains duplicate css files and another subfolder maps is created.

Is it possible to edit the config so that .maps are created next to css files?